JP7137302B2 - Control method for secondary battery manufacturing system - Google Patents

Description

The present invention relates to a secondary battery manufacturing system such as a lithium ion secondary battery.

Secondary batteries are expected to be used as domestic storage batteries for temporarily storing power generated by power generation devices such as solar cells and fuel cells. Domestic storage batteries generally have a structure in which a plurality of secondary batteries are electrically connected in series to increase the voltage and increase the charge/discharge capacity of the entire storage battery (for example, Patent Document 1).

By the way, even if secondary batteries of the same type and shape are used, secondary batteries connected in series in a household storage battery may have different capacities in a group of secondary batteries due to individual differences in manufacturing. There is a problem that over-discharging and over-charging tend to occur in a secondary battery with a small capacity.
Therefore, in the production of storage batteries, the secondary batteries manufactured are sorted according to the quality of battery characteristics such as output, secondary batteries with similar quality are extracted, and secondary batteries with similar quality are connected in series. A storage battery is formed by assembling secondary battery units that are connected or connected in parallel.
In addition, there is Patent Document 2 as a publication related to storage batteries.

International Publication No. 2016-129527 JP 2013-25323 A

By the way, in the production of secondary batteries, the quality of products varies as a result due to the production environment, wear and error of equipment used in each production process, and the like. For example, even if the ambient temperature setting is 25 degrees, the measured temperature fluctuates from the set temperature to 24.8 degrees or 25.2 degrees. Therefore, conventionally, for each variation in each process, the manufacturing parameters in the manufacturing process are finely adjusted to as many secondary batteries as possible. are maintained at a certain level of quality.

However, when manufacturing secondary batteries over a long period of time, the range of fluctuations in manufacturing parameters increases, and it becomes difficult to keep the quality within a certain range only by adjusting the manufacturing parameters of individual manufacturing processes due to the accumulation of fine adjustments. Moreover, it becomes difficult to secure a certain level of quality. As a result, the quality of secondary batteries manufactured as shown in FIG. 17 tends to be generally degraded. That is, in the manufacture of secondary batteries, the manufacturing parameters of each manufacturing process are intricately intertwined. Therefore, if the manufacturing parameters of multiple manufacturing processes are adjusted, it becomes difficult to ensure quality by adjusting the manufacturing parameters for each manufacturing process. The quality of manufactured secondary batteries may deteriorate and vary.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a secondary battery manufacturing system capable of continuously manufacturing secondary batteries of a certain quality or higher.

In order to solve the above-mentioned problems, the present inventor extracts dominant parameters that affect quality deterioration from each manufacturing process, and restores the parameters to the default parameters or the default parameters. By doing so, the quality of secondary batteries can be improved, and the number of secondary batteries with a certain quality or higher can be greatly increased. However, as described above, the quality of the secondary battery is intricately intertwined with the parameters of each manufacturing process, and it is artificially difficult to extract the dominant parameter from a huge number of parameters. Therefore, the present inventor linked the huge amount of manufacturing parameters acquired during manufacturing so far and the evaluation results of evaluating the quality of secondary batteries manufactured with these manufacturing parameters, and used artificial intelligence and the like. By machine learning the correlation between manufacturing parameters and quality using a machine learning device, the dominant parameter that induces quality deterioration is identified from the quality of the manufactured secondary battery, and the quality is improved by adjusting the parameter. We thought that it would be possible to continuously manufacture secondary batteries that have been improved and have a certain level of quality or higher.

The invention according to claim 1, which was derived based on such considerations, includes a control unit, a manufacturing unit that automatically performs a part or all of the manufacturing process of the secondary battery, and the an evaluation unit that evaluates the quality of the secondary battery, the control unit has a storage unit and a machine learning unit, and is capable of controlling manufacturing parameters used in manufacturing in the manufacturing unit; The storage unit stores current and past manufacturing parameters in association with evaluation results of the secondary battery manufactured using the past manufacturing parameters by the evaluation unit, and the control unit stores the secondary battery It is determined whether the quality of the battery has deteriorated below a predetermined standard, and when it is determined that the quality of the secondary battery manufactured by the manufacturing unit has deteriorated below the predetermined standard, the storage unit stores the Based on the relationship between the past manufacturing parameters and the past evaluation results, identify the trigger parameters that affect the deterioration of quality from among the manufacturing parameters, and return the trigger parameters to the manufacturing parameters at the time of initial setting. A control method for a secondary battery manufacturing system.
The present invention comprises a control unit, a manufacturing unit that automatically performs part or all of the manufacturing process of a secondary battery, and an evaluation unit that evaluates the quality of the secondary battery manufactured by the manufacturing unit, The unit has a storage unit and a machine learning unit, and is capable of controlling manufacturing parameters used for manufacturing in the manufacturing unit, and the storage unit stores past manufacturing parameters and the past manufacturing parameters The evaluation result by the evaluation unit of the secondary battery manufactured using , based on the relationship between the past manufacturing parameters and the past evaluation results stored in the storage unit, specifying the inducement parameter that affects quality deterioration from among the manufacturing parameters, and setting the inducement parameter as the manufacturing parameter at the time of initial setting. It relates to a secondary battery manufacturing system that approximates or restores manufacturing parameters to the initial settings.

Here, "the quality of the secondary battery has fallen below a predetermined standard" means that the quality of the secondary battery does not satisfy the specified standard range.
Here, "returning to the manufacturing parameters at the time of initial setting" means returning to the state of initial setting, and includes the case where the member itself is replaced with a new one.

The invention according to claim 2 is for manufacturing a plurality of secondary batteries simultaneously or continuously, extracting a predetermined number of secondary batteries from the plurality of secondary batteries, 2. The second method according to claim 1, wherein the machine learning unit determines that the quality of the secondary battery has deteriorated when the percentage of batteries whose quality falls within a predetermined range is below a predetermined threshold. A control method for a secondary battery manufacturing system.

In the invention according to claim 3, the manufacturing process of the secondary battery includes at least a slurry forming process, a coating process, an electrode body forming process, and an extraction electrode connecting process, and the slurry forming process It is a step of kneading at least an electrode active material, a solvent and a binder with a propeller to form a slurry electrode material, and the coating step is to apply the slurry electrode material to a metal foil and dry it to form an electrode. the step of forming an electrode body is a step of stacking the electrode and the separator to form an electrode body; the step of connecting the extraction electrode is a step of connecting the extraction electrode to the electrode assembly by welding; 3. The method of controlling a secondary battery manufacturing system according to claim 1, wherein the manufacturing parameters include parameters (1) to (4) below.
(1) At least one parameter selected from kneading temperature, environmental temperature, environmental humidity, viscosity of electrode material, number of revolutions of electric propeller, and driving power of electric propeller in the slurry forming step.
(2) At least one parameter selected from environmental temperature, environmental humidity, viscosity of the electrode material, coating speed, electrode thickness, drying temperature, and drying atmosphere in the coating step.
(3) At least one parameter selected from environmental temperature, environmental humidity, contact area between electrodes and separators, number of overlapping electrodes and separators, and overlapping order of electrodes and separators in the electrode body forming step.
(4) At least one parameter selected from environmental temperature, environmental humidity, welding temperature, welding pressure, holding time, and welding sensing timing in the extraction electrode connecting step.

The term "power for driving the electric propeller" used herein refers to power supplied to drive the electric propeller.
"Environmental temperature" is the temperature of the environment to which the work-in-progress or product is exposed when performing the process, for example, when the manufacturing process is performed in a dry room, it means the temperature in the dry room.
The term "environmental humidity" refers to the humidity of the environment to which the work-in-progress or product is exposed when the manufacturing process is performed. For example, when the manufacturing process is performed in a dry room, it means the humidity in the dry room.
"Drying temperature" refers to the ambient temperature of the work-in-process product exposed when drying the work-in-process product in the coating process.
The term "drying humidity" refers to the humidity around the work-in-progress that exposes the work-in-progress when drying the work-in-progress in the coating process.
The term "drying atmosphere" refers to the gas surrounding the work-in-progress that exposes the work-in-progress when drying the work-in-progress in the coating process.
The term "contact area between the electrode and the separator" refers to the area where the electrode and the separator are in contact. For example, in the case of a laminated secondary battery, it may be the area where one electrode and one separator come into contact, or the total area where the electrode and the separator come into contact.
"The number of overlapping electrodes and separators" refers to the number of overlapping electrodes and separators. For example, in the case of a laminated secondary battery, it refers to the number of laminations, and in the case of a wound secondary battery, it refers to the overlapping number of a part of the inner and outer electrodes and a part of the separator in the radial direction.
"The order in which the electrodes and the separators overlap" means the order in which the electrodes and the separators overlap. For example, in the case of a laminated secondary battery, it refers to the stacking order in the stacking direction. Say.
"Welding sensing timing" refers to the timing at which welding is determined to be completed.

In the invention according to claim 4, the manufacturing process of the secondary battery includes an electrode forming process in which the electrode is cut by a cutting unit of an electrode cutting machine and the shape of the electrode is adjusted, and the manufacturing parameters are as follows: 4. The method of controlling a secondary battery manufacturing system according to claim 3, wherein the parameter (5) is included.
(5) At least one parameter selected from environmental temperature, environmental humidity, the number of burrs generated on the electrode after cutting, and the area of burrs on the electrode body after cutting in the electrode forming step.

Here, "the number of burrs generated on the electrode after cutting" means the number of burrs generated on the edge of the electrode by the cut portion.
Here, "the area of burrs on the electrode body after cutting" refers to the area of one burr or the total area of burrs formed on the edge of the electrode by the cut portion.

In the invention according to claim 5, the manufacturing parameter includes the number of burrs generated on the electrode after cutting in the electrode forming step or the area of burrs on the electrode body after cutting, and the trigger parameter is the number of burrs generated on the electrode after cutting. 5. The control of the secondary battery manufacturing system according to claim 4, wherein when the number of burrs generated or the burr area of the electrode body after cutting is specified, the cutting part of the electrode cutter is replaced. The method .

In the invention according to claim 6, the manufacturing process of the secondary battery includes a vacuum drying process in which the electrode body is housed in a bag-like sealing member and dried while being vacuumed by a vacuum pump; An electrolytic solution injection step of injecting a liquid into the sealing member to weld and seal a part of the sealing member, and the manufacturing parameters include parameters (6) and (7) below. 6. A control method for a secondary battery manufacturing system according to any one of claims 3 to 5, characterized by:
(6) At least one parameter selected from drying temperature, drying humidity, degree of vacuum, and power consumption of a vacuum pump in the vacuum drying step.
(7) Environmental temperature, environmental humidity, welding temperature of the sealing member, welding pressure of the sealing member, welding time of the sealing member, sensing timing of the sealing member, and the electrolysis in the electrolytic solution injection step At least one parameter selected from the injection amount of the liquid and the concentration of the electrolyte.

The term "sealing member sensing timing" as used herein refers to the timing at which it is determined that the welding of the sealing member has been completed.

In the invention according to claim 7, the manufacturing process of the secondary battery includes an electrode rolling process of rolling the electrode by sandwiching it between a pair of rolls, and the manufacturing parameters include parameters of (8) below. The method for controlling a secondary battery manufacturing system according to any one of claims 3 to 6, characterized in that:
(8) At least one parameter selected from environmental temperature, environmental humidity, rotation speed of the pair of rolls, gap between the pair of rolls, electrode density after rolling, and electrode thickness in the electrode rolling step.

The term "electrode density after rolling" as used herein refers to the weight of the electrode per unit volume after the electrode rolling process, and can be calculated from the thickness and weight of the electrode of a predetermined size excluding the metal foil.

According to an eighth aspect of the invention, the secondary battery manufacturing process includes an electrode forming process including at least a slurry forming process, a coating process, and a rolling process, and the slurry forming process is performed by an electric propeller. and a step of kneading at least an electrode active material, a solvent and a binder to form a slurry electrode material, and the coating step is a step of applying the slurry electrode material to a metal foil and drying it to form an electrode. and the rolling step is a step of rolling the metal foil on which the electrodes are formed, and the electrode forming step is automatically performed. A control method for a secondary battery manufacturing system.

According to a ninth aspect of the invention, the machine learning unit performs supervised learning, and learns the relationship between past manufacturing parameters and past evaluation results stored in the storage unit as teacher data. 9. A control method for a secondary battery manufacturing system according to any one of claims 1 to 8, characterized by:

The invention according to claim 10 is characterized in that the machine learning unit is a deep learning unit that learns according to a neural network of four or more layers. A control method for a battery manufacturing system.

According to the secondary battery manufacturing system of the present invention, the machine learning unit identifies the inducement parameter that induces quality deterioration from among the production parameters of the secondary battery, and restores the inducement parameter to the parameter at the time of initial setting. Secondary batteries of higher quality can be continuously manufactured.
According to the secondary battery manufacturing system to which the present invention relates, the machine learning unit identifies the triggering parameter that induces quality deterioration from among the manufacturing parameters of the secondary battery, and brings the triggering parameter closer to the parameter at the time of initial setting, or Since the parameters are returned to the initial settings, it is possible to continuously manufacture secondary batteries of a certain quality or higher.

1 is a block diagram of a secondary battery manufacturing system according to a first embodiment of the present invention; FIG. FIG. 2 is a perspective view schematically showing a main part of the first kneading and coating device of FIG. 1; 1. It is a perspective view which represents typically the condition which is performing a coating process and a drying process using the 1st kneading coating apparatus of FIG. 1. It is a perspective view which represents typically the condition which is performing a coating process and a drying process using the 2nd kneading coating apparatus of FIG. 1. It is a perspective view which represents typically the condition which is performing the electrode rolling process using the press apparatus of FIG. FIG. 2 is a perspective view schematically showing a situation in which the metal foil of the electrode after the coating process is punched out using the punching device of the forming apparatus of FIG. 1 to form a connecting portion; FIG. 2 is a perspective view schematically showing a state in which electrodes are formed using the cutting device of FIG. 1; FIG. 2 is a perspective view schematically showing a state in which an electrode body forming step is performed using the electrode stacking apparatus of FIG. 1; FIG. 2 is an explanatory view of an extraction electrode connection process using the welding apparatus of FIG. 1, where (a) is a perspective view schematically showing a state in which a tab electrode member is placed on an electrode body, and (b) is a welding portion; FIG. 4C is a perspective view schematically showing a state immediately before the horn portion is pressed against the tab electrode member, and FIG. 1. It is a perspective view which represents typically the condition which is performing the 1st lamination process using the 1st welding apparatus of the sealing apparatus of FIG. 1. It is a perspective view which represents typically the condition which is performing the vacuum-drying process and the liquid injection process using the vacuum drying apparatus and electrolyte injection apparatus of the sealing apparatus of FIG. 1. It is a perspective view which represents typically the condition which is performing the 2nd lamination process using the 2nd welding apparatus of the sealing apparatus of FIG. 2 is a flowchart of parameter adjustment operation of the secondary battery manufacturing system of FIG. 1; 2 is a graph showing an example of the quality distribution of a group of secondary batteries manufactured by the secondary battery manufacturing system of FIG. , and (b) represents the distribution when the number of quality exceeds a predetermined threshold is large. FIG. 2 is an explanatory diagram of the deep learning unit in FIG. 1, where (a) is a schematic diagram showing a neuron model, and (b) is a schematic diagram showing a neural network model; FIG. 2 is an explanatory diagram showing an example of a secondary battery manufactured by the secondary battery manufacturing system of FIG. 1, where (a) is a perspective view of the secondary battery and (b) is a cross-sectional view taken along the line AA of (a). (c) is a cross-sectional view taken along the line BB of (a). FIG. 4 is a graph showing variations in quality distribution of secondary batteries, where the solid line represents a normal state and the two-dot chain line represents a state of degraded quality.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. Unless otherwise specified, physical properties are based on 25 degrees Celsius and 1 atmosphere.

A secondary battery manufacturing system 1 according to the first embodiment of the present invention is an apparatus for manufacturing a secondary battery 200. As shown in FIG. A control unit 3 that controls the manufacturing process in the manufacturing unit 2 , and an evaluation unit 4 that evaluates the performance of the secondary battery 200 manufactured by the manufacturing unit 2 .
Then, the secondary battery manufacturing system 1 of the present embodiment extracts a specific secondary battery 200 every time a predetermined number of secondary batteries 200 are manufactured, or all the secondary batteries 200 are evaluated by the evaluation unit 4. Performance is evaluated, and when the evaluation result by the evaluation unit 4 is lower than a predetermined standard, the deep learning unit 170 (machine learning unit) of the control unit 3 uses the past parameters and the past parameters stored in the data storage unit 171 The main feature is to select an incentive parameter that affects the lowered evaluation result from the evaluation result, and perform parameter adjustment operation to bring the incentive parameter closer to the manufacturing parameter at the time of initial setting or return it to the manufacturing parameter at the time of initial setting. be one.
Based on this fact, each configuration of the secondary battery manufacturing system 1 of the present embodiment will be described below.

As shown in FIG. 1, the production unit 2 includes an electrode forming device 5 (5a, 5b), an electrode stacking device 6, a welding device 7, and a sealing device 8, which are controlled by the control unit 3. ing.

The electrode forming devices 5a and 5b are devices for forming the respective electrodes 210 and 211 (see FIG. 16) of the secondary battery 200, and include a first kneading and coating device 20, a second kneading and coating device 21, and a press device. 22 and a molding device 23 .
Since the electrode forming apparatus 5a for forming the positive electrode 210 and the electrode forming apparatus 5b for forming the negative electrode 211 are structurally similar, only the configuration of the electrode forming apparatus 5a will be described below, and the configuration of the electrode forming apparatus 5b will be described. , the description is omitted. In addition, members common to the first kneading and coating device 20 and the second kneading and coating device 21 are assigned common numbers and description thereof is omitted.

The first kneading and coating device 20 kneads an electrode material containing an electrode active material, a solvent, a conductive aid, and a binder that constitute the electrode layer 201 a (electrode layer 201 b ) of the secondary battery 200 . It is an apparatus for forming an electrode 210 (electrode 211) by coating an electrode layer 201a (electrode layer 201b) on the main surface.
As can be seen from FIGS. 2 and 3, the first kneading and coating device 20 includes a material supply unit 30, a material delivery unit 31, and a manufacturing chamber (not shown) in which the environment such as temperature and humidity can be adjusted. A discharge device 32 , a conveying device 33 and a drying device 34 are provided.

As shown in FIG. 2, the material supply unit 30 includes a material container 40 and a kneading device 41. An electrode material such as an electrode active material put into the material container 40 is kneaded by the kneading device 41 to form a slurry. This is a portion for supplying into the cylinder portion 55 of the material delivery portion 31 .
The material container 40 is a hopper that stores an electrode material such as an electrode active material, and is a funnel-shaped container with an open top.
A supply port 42 is provided at the lower end of the material container 40 and is connected to the material delivery section 31 via the supply port 42 .

The kneading device 41 includes a lid portion 45 and an electric propeller portion 46 as shown in FIG.
The lid portion 45 is a lid that closes the upper portion of the material container 40 and seals the space inside the material container 40 .
The electric propeller section 46 is composed of a drive motor 47 , a propeller body 48 and a shaft section 49 . The electric propeller section 46 connects the shaft section 49 to the rotating shaft of the drive motor 47 and drives the drive motor 47 so that the electrode material can be kneaded by the propeller body 48 .
The drive motor 47 is a motor that rotates the propeller body 48, and the rotational speed of the propeller body 48 can be controlled by the external controller 3 (see FIG. 1).

The material delivery section 31 includes a cylinder section 55, a screw section 56, and a drive motor 57, as shown in FIG. By driving the drive motor 57, the material feeding section 31 rotates the screw section 56 in the cylinder section 55, scrapes the electrode material kneaded by the kneading device 41 from the material container 40, and further stirs the electrode material. It is a device that advances the inside of the cylinder portion 55 and sends it out to the discharging device 32 .
The cylinder part 55 is a cylindrical part that is connected to the supply port 42 of the kneading device 41 and accommodates the electrode material in a slurry state.
The screw portion 56 is a screw having helical blades and is inserted into the cylinder portion 26 .
The drive motor 57 is a motor that rotates the screw portion 56 , and the rotational speed of the screw portion 56 can be controlled by the external controller 3 .
The cylinder portion 55 is located below the material container 40 and extends in a direction crossing the axis of the material container 40 . The lower part of the material container 40 and the inside of the cylinder part 55 communicate with each other. The longitudinal direction of the cylinder portion 55 coincides with the axial direction of the rotation shaft of the drive motor 57 .

The discharging device 32 discharges the slurry-like electrode material kneaded by the kneading device 41 and the screw part 56 so as to have a predetermined thickness with respect to the metal foil 202 as a current collector, and forms an electrode layer on the metal foil 202. 201 is applied.
As shown in FIG. 2, the ejection device 32 includes a cavity portion 60 for temporarily retaining the slurry-like electrode material, an ejection port 61 for ejecting the electrode material, and an adjusting member 62 for adjusting the width of the ejection port 61. there is
As shown in FIG. 3, the discharge port 61 is a slit extending linearly in a direction orthogonal to the flow direction MD of the metal foil 202 conveyed by the conveying device 33 .
The adjusting member 62 is a member for controlling the opening width of the ejection port 61 , and is configured by arranging adjustment bolts in parallel in the longitudinal direction of the ejection port 61 .

As shown in FIG. 3, the conveying device 33 includes a material reel portion 65, conveying rollers 66a to 66c, and a pressing roller 67, and conveys the metal foil 202 downstream (second kneading and coating device 21 side). It is a device that
The material reel portion 65 is a portion to which a metal foil reel around which the metal foil 202 is wound is attached, and the metal foil 202 of the metal foil reel flows downstream.
The transport rollers 66a to 66c are rollers that transport the metal foil 202 downstream.
The pressing roller 67 is a roller that applies tension to the metal foil 202 by pressing the metal foil 202 having the electrode layer 201 formed by applying a slurry electrode material on one side thereof.

The drying device 34 is a device for passing the metal foil 202 coated with the electrode layer 201 on one side and evaporating water, solvent, and the like from the electrode layer 201 .
The drying device 34 includes a heating device, a dehumidifying device, and an atmosphere control device, and can dry the metal foil 202 coated with the electrode layer 201 at a desired drying temperature, drying humidity, and drying atmosphere.

The second kneading and coating device 21, like the first kneading and coating device 20, kneads the electrode material, and the other main surface of the metal foil 202 (the surface opposite to the surface coated with the electrode layer 201). It is an apparatus for forming an electrode 210 (electrode 211) by coating an electrode layer 201 on the surface.
As shown in FIG. 4, the second kneading and coating device 21 includes a material supply unit 30, a material delivery unit 31, and a discharge device 32 in a manufacturing room (not shown) in which environmental conditions such as temperature and humidity can be adjusted. , a conveying device 36 and a drying device 34 .
The conveying device 36 does not have the material reel portion 65 as shown in FIG.

The press device 22 located downstream of the second kneading and coating device 21 includes a pair of rolling rolls 70 and 71 and a plurality of transport rollers 72a and 72b as shown in FIG. It is a rolling device that rolls the layer 201 to a predetermined thickness.
That is, the press device 22 compresses the electrode 210 (electrode 211) with the rolling rolls 70 and 71 while conveying the electrode 210 (electrode 211) with the conveying rollers 72a and 72b, thereby forming the electrode layer 201 on the metal foil 202. The thickness and density are adjustable.
The press device 22 is connected to the control unit 3 and is capable of adjusting the interval between the rolling rolls 70 and 71 and the rotational speed of the rolling rolls 70 and 71 .

The shaping device 23 is a device that cuts and shapes the electrode 210 (electrode 211) into a predetermined size.
As shown in FIGS. 6 and 7, the molding device 23 includes a punching device 80 (electrode cutting machine) and a first cutting device 81 (electrode cutting machine) in a dry room in which environmental conditions such as temperature and humidity can be adjusted. , a second cutting device 82 (electrode cutting machine) and a conveying device 83 .

As shown in FIG. 6, the punching device 80 is a cutting device for cutting a part of the electrode 210 (electrode 211). 214).
The punching device 80 can punch out the metal foil 202 in a rectangular wave shape, and can form a rectangular connecting portion 205 at a cut portion (not shown).

The first cutting device 81 is a cutting device that cuts a part of the electrode 210 (electrode 211), as shown in FIG. 211) in the flow direction MD.
The second cutting device 82 is a cutting device that cuts a part of the electrode 210 (electrode 211), has a cutting tooth 91, and rotates the cutting tooth 91 (cutting portion) to cut the electrode 210 (electrode 211). in the width direction TD.

The conveying device 83 is composed of a plurality of conveying rollers 94a and 94b for passing the electrode 210 (electrode 211) through the punching device 80, and a plurality of conveying conveyors 95a to 95d for passing the cutting devices 81 and 82.
The transport conveyors 95 a to 95 d are belt conveyors, each having a belt member 96 and rotating rollers 97 . Of the conveyors 95a to 95d, the most downstream conveyors 95c and 95d are one step lower than the conveyor 95b, and a sorting member 98 is arranged between the conveyors 95c and 95d.
The separating member 98 is a member that separates the electrodes 210 (electrodes 211) separated by the second separating device 82, and is erected from between the conveyors 95c and 95d to the uppermost surfaces of the conveyors 95c and 95d. It is

The electrode forming apparatus 5b has the same structure as that of the electrode forming apparatus 5a as described above, and is the same except for forming the negative electrode layer 201b, so that the description thereof is omitted.

The electrode stacking device 6 is a device for forming an electrode body 218 in which electrodes 210 and 211 and separators 212 are alternately stacked.
As shown in FIG. 8, the electrode stacking apparatus 6 includes electrode transfer lines 100 and 101, a separator transfer line 102, a stage 103, and a dry room (not shown) in which environmental conditions such as temperature and humidity can be adjusted. A cell transport line 105 is provided.
The electrode transfer lines 100 and 101 are transfer lines through which the electrodes 210 and 211 are transferred from the transfer conveyor 95c or the transfer conveyor 95d of the forming device 23 of the electrode forming devices 5a and 5b. That is, the electrode transport line 100 transports the positive electrode 210 manufactured by the electrode forming apparatus 5a, and the electrode transport line 101 transports the negative electrode 211 manufactured by the electrode forming apparatus 5b.
The separator conveying line 102 is a conveying line along which a separator 212 cut into a predetermined shape is conveyed.
The downstream ends of the electrode transport lines 100 and 101 and the separator transport line 102 face the stage 103 .
The stage 103 is arranged on the cell transport line 105, and is a part for stacking the electrodes 210, 211 and the separator 212 transported from the transport lines 100 to 102 in a predetermined stacking order.
The cell transport line 105 is a transport line that transports the electrodes 210 and 211 and the separator 212 laminated on the stage 103 to the welding device 7 .

The welding device 7 welds the tab electrode members 213 and 214 to the connecting portions 205a and 205b of the electrode body 218 using ultrasonic waves, and is specifically an ultrasonic welding device.
As shown in FIG. 9, the welding device 7 has a robot arm (not shown), a holding part 110, a welding part 111, and a photographing unit in a dry room (not shown) in which environmental conditions such as temperature and humidity can be adjusted. means (not shown).
The robot arm is a device that moves the stage 103 transported by the cell transport line 105 to a desired position, and also a device that places the tab electrode members 213 and 214 on the electrode body 218 on the stage 103 .
The holding part 110 is a part that fixes and positions the stage 103 .

As shown in FIG. 9, the welding portion 111 includes a body portion 115 and horn portions 116a and 116b.
The body portion 115 is a portion that incorporates an ultrasonic transducer and applies a load to the electrode body 218 side in the stage 103 via the horn portions 116a and 116b.
The horn portions 116 a and 116 b are portions that resonate with the ultrasonic transducer of the main body portion 115 and apply vibration and load to the electrode body 218 and the tab electrode members 213 and 214 .
The photographing means is a device that photographs the interface between the electrode body 218 and the tab electrode members 213 and 214 to detect the welding state.

As can be seen from FIGS. 10, 11 and 12, the sealing device 8 includes a first welding device 130 and a vacuum drying device 131 in a dry room (not shown) in which environmental conditions such as temperature and humidity can be adjusted. , an electrolyte injection device 132 and a second welding device 133 .
The first welding device 130 welds the two laminate films 230 and 231 in a state in which at least the electrode body 218 is sandwiched between the two laminate films 230 and 231. It is an apparatus for forming a container containing the body 218 and the like.

The first welding device 130 includes a robot arm (not shown) and a pair of welding members 135 and 136, as shown in FIG.
The welding members 135 and 136 both spread out in a planar manner, and have welding portions 137 and 138 on opposite surfaces.
The welding portions 137 and 138 are U-shaped, and can weld the three sides of the laminate films 230 and 231 around the electrode body 218 by heating or pressing.

The vacuum drying device 131 is a device for vacuum drying the electrode body 218 and the like, and includes a vacuum drying chamber 140 and a conveying device 141 as shown in FIG.
The vacuum drying chamber 140 includes a main body 146 having openings 145a and 145b on upstream and downstream sides in the transport direction, door members 147a and 147b for opening and closing the openings 145a and 145b, and a vacuum pump 148. In the vacuum drying chamber 140, the inside of the body portion 146 can be made into a substantially vacuum space by closing both the door members 147a and 147b and driving the vacuum pump 148. As shown in FIG.
The conveying device 141 is a device that conveys the electrode body 218 placed on the stage 150 and covered with the laminate films 230 and 231, and is specifically a roller conveyer.

The electrolytic solution injection device 132 is a device for injecting the electrolytic solution 215 through the openings of the laminate films 230 and 231, and includes an injection section 155 and a conveying device 156 as shown in FIG.
The injection part 155 has a nozzle for injecting the electrolytic solution 215 from an electrolytic solution tank (not shown).
The conveying device 156 is a device for conveying the vacuum-dried electrode body 218 and the like, and a roller conveyer or a belt conveyer can be employed.

The second welding device 133 is a vacuum welding device that welds the openings of the laminate films 230 and 231 while drawing a vacuum, and as shown in FIG. .
The welding part 160 is a part that welds the vicinity of the openings of the laminate films 230 and 231 to seal the electrode body 218 inside the laminate films 230 and 231 .
The vacuum pump 161 is a device that is connected to the welding portion 160 and vacuums the laminate films 230 and 231 passing through the welding portion 160 .
The conveying device 162 is a device for conveying the electrode body 218 and the like, and a roller conveyer or a belt conveyer can be adopted.

As shown in FIG. 1, the control unit 3 is connected to the manufacturing unit 2 and the evaluation unit 4 via a wireless or wired connection, and can acquire manufacturing parameters in the manufacturing unit 2 and evaluation results from the evaluation unit 4. ing.
The control unit 3 may be provided in a building different from the manufacturing unit 2 and the evaluation unit 4 . In this case, it is preferable that the control section 3 is interconnected with the manufacturing section 2 and the evaluation section 4 via a network such as an intranet so as to be able to communicate with each other. Also, the control unit 3 may be connected to the manufacturing unit 2 and the evaluation unit 4 via the Internet or the like. By doing so, it is possible to collectively manage the manufacturing department 2 and the evaluation department 4 at a plurality of bases in different buildings.

As shown in FIG. 1, the control unit 3 includes, as main components, a deep learning unit 170 (machine learning unit), a data storage unit 171 (storage unit), an evaluation result acquisition unit 172, a determination unit 173, and an output A control unit 174 is provided.
The deep learning unit 170 has a function of performing machine learning by itself using the past manufacturing parameters, evaluation results, and judgment results accumulated in the data accumulation unit 171, and based on the learning, there are incentives that induce quality deterioration. A parameter can be specified and stored in the data storage unit 171 .

The deep learning unit 170 of the present embodiment has a function of learning by so-called supervised learning, and is capable of supervised learning according to an algorithm such as a neural network, which will be described later.
Here, “supervised learning” means that by giving a large amount of teacher data, that is, a set of certain input and result data to the deep learning unit 170, learning features in those data sets, is a model (error model) for estimating , that is, the relationship between input and result is acquired inductively.
That is, the deep learning unit 170 associates past manufacturing parameter variations with the evaluation results and determination results of the secondary battery 200 manufactured using the manufacturing parameters, and the manufacturing parameter variations and the secondary battery 200 to learn correlations with the quality of Then, when the quality falls below a certain standard, it is possible to extract trigger parameters that mainly cause quality deterioration based on the correlation with the quality of the secondary battery 200 .
The details of the deep learning unit 170 of this embodiment will be described later.

The data accumulation unit 171 includes a storage device such as a memory or a hard disk, and stores and accumulates past and present manufacturing parameters in the manufacturing unit 2, evaluation results in the evaluation unit 4, and judgment criteria in the judgment unit 173. is.
The evaluation result acquisition unit 172 is a part that acquires the evaluation results of the secondary battery 200 from each of the evaluation devices 11 to 16 and transmits them to the data storage unit 171 and the determination unit 173 .
The determination unit 173 is a part that determines the quality of the secondary battery 200 based on the evaluation result of the secondary battery 200 acquired by the evaluation result acquisition unit 172 and the determination criteria stored in the data storage unit 171 .
The output control unit 174 is a part that controls the manufacturing parameters of the devices 5 to 8 of the manufacturing unit 2 and transmits the used or measured manufacturing parameters to the data storage unit 171 . The output control unit 174 is also a part that controls the trigger parameters extracted by the deep learning unit 170 .

The evaluation unit 4 includes an electrical property evaluation device 11, a resistance property evaluation device 12, a shape evaluation device 13, and a structure evaluation device 14, as shown in FIG.
The electrical characteristic evaluation device 11 is a device that evaluates the electrical characteristics of the secondary battery 200, and is a device that performs a charge/discharge cycle test, a charge/discharge characteristic test, a constant current test, a rate characteristic test, and an overcharge test.
The resistance characteristic evaluation device 12 is a device that evaluates the resistance characteristics of the secondary battery 200 and is a device that measures impedance.
The shape evaluation device 13 is a device that evaluates the external shape of the secondary battery 200, measures dimensions, volume, and weight, and evaluates the occurrence of expansion and the like.
The structure evaluation device 14 is a device that evaluates the structure and the like of the secondary battery 200, and is, for example, an abnormality detection device that detects an abnormality by observing the internal structure with an X-ray CT device.

Next, main steps in manufacturing the secondary battery 200 using the secondary battery manufacturing system 1 will be described.

First, an electrode forming process for forming the electrodes 210 and 211 is performed.
The electrode forming process includes a slurry forming process, a sending process, a coating process, a drying process, and a rolling process as main processes.
In the electrode forming process, first, a slurry forming process is performed, and electrode materials such as an electrode active material, a solvent, a conductive aid, and a binder are introduced into the material container 40 and kneaded by the electric propeller section 46 until a predetermined viscosity is achieved. to form a fluid slurry electrode material.

At this time, the environmental temperature (temperature in the manufacturing room), the environmental humidity (humidity in the manufacturing room), the kneading temperature and kneading humidity in the material container 40, the drive power when the drive motor 47 is driven, the rotation speed of the electric propeller part 46, The viscosity of the electrode material is detected and transmitted to the data accumulation section 171 of the control section 3 as a manufacturing parameter.
It should be noted that it is not necessary to measure the viscosity all the time, and the viscosity of the slurry electrode material may be measured at any timing.

After the slurry-like electrode material is formed in the kneading device 41 by the slurry forming step, the electrode material is introduced from the supply port 42 into the cylinder portion 55 of the material delivery portion 31 as shown in FIG. The electrode material is sent out to the cavity portion 60 of the ejection device 32 while being kneaded with (a delivery step).

At this time, the temperature and humidity in the cylinder part 55, the drive power when the drive motor 57 is driven, the number of revolutions of the screw part 56, and the viscosity of the electrode material are detected and sent to the data storage part 171 of the control part 3 as manufacturing parameters. do.

When the slurry-like electrode material reaches the cavity portion 60, as shown in FIG. An electrode material is applied onto one main surface of the metal foil 202 at a coating start portion 68 between 66b and the pressing roller 67 to form the electrode layer 201 (coating step). Then, the metal foil 202 having the electrode layer 201 formed on one side and passed through the pressing roller 67 passes through the drying device 34 (drying step), is reversed by a reversing device (not shown), and is conveyed to the second kneading and coating device 21. be done.

At this time, in the coating process and the drying process, the environmental temperature (temperature in the manufacturing room), the environmental humidity (humidity in the manufacturing room), the opening width of the discharge port 61, the coating speed, the top of the conveying roller 66b and the pressing roller 67 The difference in height (height difference) from the bottom of the dryer 34, the drying temperature in the drying device 34, and the drying atmosphere are detected and transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.

The metal foil 202 that has reached the second kneading and coating device 21 is the electrode material that has been subjected to the slurry forming step and the sending step as shown in FIG. The electrode material is applied onto the other main surface of the metal foil 202 at the coating start portion 68 between the conveying roller 66b and the pressing roller 67 to form the electrode layer 201 (coating step). , an electrode 210 (electrode 211) is formed. Then, the metal foil 202 (electrode 210 (electrode 211)) having the electrode layers 201 formed on both sides passes through the drying device 34 (drying step).

Also in the second kneading and coating device 21, in the slurry forming process, the temperature and humidity in the material container 40, the amount of electric power when the drive motor 47 is driven, the rotation speed of the electric propeller section 46, and the viscosity of the electrode material are detected. and transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.
In the delivery process, the temperature and humidity in the cylinder part 55, the amount of electric power when the drive motor 57 is driven, the rotation speed of the screw part 56, and the viscosity of the electrode material are detected, and stored in the data storage part 171 of the control part 3 as manufacturing parameters. Send.
In the coating process and the drying process, the width of the opening of the discharge port 61, the coating speed, the environmental temperature (temperature in the manufacturing room), the environmental humidity (humidity in the manufacturing room), the top of the conveying roller 66d and the bottom of the pressing roller 67 , the drying temperature and the drying atmosphere in the drying device 34 are detected, and transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.

As shown in FIG. 5, the electrode 210 (electrode 211) that has passed through the drying device 34 is transported by transport rollers 94a and 94b and passed between rolling rolls 70 and 71 so that the electrode layer 201 has a predetermined electrode density. (electrode rolling process).

At this time, the environmental temperature (the temperature in the production room), the environmental humidity (the humidity in the production room), the interval between the rolling rolls 70 and 71, the rotation speed of the rolling rolls 70 and 71, the electrode density after rolling, and the thickness of the electrode layer 201 are detected and transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.

The electrode 210 (electrode 211) rolled by the rolling rolls 70 and 71 is conveyed into a dry room, and as shown in FIG. to form the connecting portion 205 . Then, as shown in FIG. 7, the electrode 210 (electrode 211) having the connection portion 205 formed thereon is transported by transport conveyors 95a and 95b and passed through the dividing devices 81 and 82 to cut the electrode 210 (electrode 211) into a desired size. Then, the electrode 210 is formed by cutting and molding (electrode molding step).

At this time, the environmental temperature (the temperature in the dry room), the environmental humidity (the humidity in the dry room), the number of burrs generated on the electrode 210 (electrode 211) after cutting, the area of the burrs, the position of the burrs, the The position and the area of the connecting portion 205 are detected and transmitted to the data accumulation portion 171 of the control portion 3 as manufacturing parameters.

The electrodes 210 formed by the dividing devices 81 and 82 are sorted by the sorting member 98 and transported to the transport conveyors 95c and 95d.

After the electrodes 210 and 211 are formed by the electrode forming apparatuses 5a and 5b, the electrodes 210 and 211 are transferred to the electrode transfer lines 100 and 101 of the electrode stacking apparatus 6, respectively.
As shown in FIG. 8, the electrodes 210 and 211 conveyed by the electrode conveying lines 100 and 101 are alternately stacked on the stage 103 together with the separators 212 conveyed by the separator conveying line 102 to form the electrode body 218. .
Specifically, from the bottom of the stage 103, the electrodes 210, 211 are arranged in order of the separator 212, the negative electrode 211, the separator 212, the positive electrode 210, the separator 212, the negative electrode 211, the separator 212, the positive electrode 210, . An electrode body 218 is formed by stacking such that the separator 212 is interposed therebetween (electrode body forming step).

At this time, the connecting portion 205a of each positive electrode 210 is positioned on the plane of projection in the thickness direction, and the connecting portion 205b of each negative electrode 211 is positioned on the plane of projection in the thickness direction.
At this time, the environmental temperature (temperature in the manufacturing room), the environmental humidity (humidity in the manufacturing room), the contact area between the electrodes 210 and 211 and the separator 212, the number of layers of the electrodes 210 and 211 and the separator 212, and the electrodes 210 and 211 , and the stacking order of the separators 212 are sent to the data storage unit 171 of the control unit 3 as manufacturing parameters.

After the electrode body 218 is formed, the stage 103 on which the electrode body 218 is laminated is transported to the welding device 7 by the cell transport line 105 together with the electrode body 218 .

When the stage 103 reaches the welding device 7, the stage 103 is moved from the cell transfer line 105 by a robot arm (not shown), adjusted in position and fixed to the holding section 110 as shown in FIG.

At this time, the stage 103 is fixed so that the connection portions 205a and 205b of the electrode body 218 inside thereof are exposed upward.

Then, as shown in FIG. 9, the tab electrode members 213 and 214 are placed on the connecting portions 205a and 205b of the electrode body 218 in the stage 103 fixed to the holding portion 110. Positioned welding portion 111 descends, and horn portions 116a and 116b press tab electrode members 213 and 214 while vibrating. , the connecting portions 205a and 205a of the electrode body 218 and the connecting portions 205b and 205b of the electrode body 218 are welded (extraction electrode connecting step).

At this time, the environmental temperature (the temperature in the dry room), the environmental humidity (the humidity in the dry room), the welding temperature, the welding pressure, the holding time, and the sensing timing of the welding by the horn parts 116a and 116b are used as production parameters, respectively. 3 data storage unit 171.

When the welding of the electrode assembly 218 and the tab electrode members 213 and 214 is completed in the lead-out electrode connection step, the electrolytic solution injection step is started, and the hold portion 110 is moved to the sealing device 8 .
In the electrolytic solution injection step, first, an electrode assembly 218 having tab electrode members 213 and 214 attached thereto is placed on the laminate film 230 placed so as to cover the welding portion 137 of the welding member 135 by a robot arm (not shown). do. Next, as shown in FIG. 10, a lamination film 231 having recesses formed in advance is covered so as to cover the electrode body 218 . Then, the welding member 136 is lowered, and the laminated film 231 is pressed by the welded portion 138 so that the three sides of the laminated films 230 and 231 are sandwiched between the welded portions 137 and 138 . In this state, the welding portions 137 and 138 are heated to weld the laminate films 230 and 231 to each other to make the laminate films 230 and 231 bag-like (first lamination step).

At this time, the environmental temperature (the temperature in the dry room), the environmental humidity (the humidity in the dry room), the welding temperature of the welded portions 137 and 138, the welding pressure of the welded portions 137 and 138, the welding time of the welded portions 137 and 138, The welding sensing timings are transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.

Subsequently, by a robot arm (not shown), the electrode body 218 covered with the laminate films 230 and 231 on three sides is placed on the stage 150 so that the openings 232 of the laminate films 230 and 231 face upward. Place. Then, as shown in FIG. 11, the substrate is transported to the vacuum drying chamber 140 of the vacuum drying device 131 by the transporting device 141, and the vacuum pump 148 is driven to perform vacuum drying for a predetermined time (vacuum drying process).

At this time, the drying temperature (temperature inside the dry room), the drying humidity (humidity inside the dry room), the degree of vacuum, and the power consumption of the vacuum pump 148 in the vacuum drying chamber 140 are stored as manufacturing parameters. 171.

When the vacuum drying is completed, the vacuum-dried electrode body 218 and the like are transported from the vacuum drying chamber 140 to the electrolytic solution injection device 132 by the transport device 141 as shown in FIG. Then, they are conveyed to the injection section 155 by the conveying device 156, and the electrolytic solution 215 is injected from the openings 232 of the laminate films 230 and 231 in the injection section 155 (injection step).

At this time, the environmental temperature (the temperature in the dry room), the environmental humidity (the humidity in the dry room), the injection amount of the electrolytic solution 215, and the concentration of the electrolytic solution 215 are sent to the data storage unit 171 of the control unit 3 as manufacturing parameters. do.

When the injection process is completed, as shown in FIG. 12, the electrode body 218 into which the liquid has been injected is transferred to the second welding device 133 by the transfer device 156, and then transferred to the transfer device 162. As shown in FIG. Then, the laminate films 230 and 231 are conveyed to the welding section 160 by the conveying device 162, and the vicinity of the opening 232 of the laminate films 230 and 231 is welded while vacuuming the welding section 160 with the vacuum pump 161 (second laminating step).

At this time, the environmental temperature (the temperature in the dry room), the environmental humidity (the humidity in the dry room), the welding temperature of the welded portion 160, the welding pressure of the welded portion 160, the welding time of the welded portion 160, and the welding sensing timing are set. It is transmitted to the data storage unit 171 of the control unit 3 as manufacturing parameters.

After that, the outside of the welded portions of the laminate films 230 and 231 is molded as necessary, and the secondary battery 200 is completed.

Next, the parameter adjustment operation of the secondary battery manufacturing system 1 of this embodiment will be described with reference to the flowchart of FIG. 13 .

In the parameter adjustment operation, first, each evaluation device 11 to 16 for a predetermined number of secondary batteries 200 (hereinafter also referred to as a secondary battery group) manufactured simultaneously or continuously within a certain period by the manufacturing department 2 Perform quality evaluation (step 1). In this embodiment, a certain number (for example, 500) of secondary batteries 200 manufactured at the same time by the manufacturing department 2 are collectively extracted as a secondary battery group, and the quality of part or all of the secondary battery group is determined. is evaluated by each evaluation device 11-16.

The evaluation result acquisition unit 172 of the control unit 3 acquires the quality evaluation result of the secondary battery group by each of the evaluation devices 11 to 16, and the determination unit 173 determines the quality of the secondary battery group from the quality evaluation result of the secondary battery group. Quantification is performed comprehensively, and the quality distribution of the secondary battery group as shown in FIG. 14 is calculated. Then, as shown in FIG. 14A, the ratio of the secondary batteries 200 whose quality is equal to or higher than a predetermined standard in the secondary battery group (hatched portion S in FIG. When the ratio of those falling within the range of between falls below a predetermined threshold value, it is determined that the quality of the secondary battery 200 has deteriorated below a predetermined standard (Yes in step 2), and the deep learning unit 170 learns and derives in advance. Based on the correlation between the variation of the manufacturing parameter obtained and the quality of the secondary battery 200, one or more triggers that cause quality deterioration among the manufacturing parameters used in the secondary battery group and stored in the data storage unit 171 Identify parameters (step 3).
At this time, the threshold for the proportion of the secondary battery 200 is preferably 50% or more, more preferably 60% or more. The percentage threshold of the secondary battery 200 is preferably 99% or less, more preferably 90% or less.
Quality is mainly classified into four types, namely design quality, facility quality, defect quality, and quality for use in sampling inspection. Design-related quality is judged based on the usable amount of battery members according to the shape of the battery. For example, the more electrodes left after punching, the lower the design-related quality. Equipment-related quality is judged based on the electrode material that remains in the manufacturing equipment. , means that the quality of the equipment is poor. The quality related to defects refers to the quality when the secondary battery manufactured as the final product does not have the desired characteristics. The quality for use in sampling inspection refers to the quality when the product cannot be shipped because it has been used in sampling inspection. Considering the trade-off between the four qualities, the above threshold is considered effective.

When the deep learning unit 170 identifies the inducement parameter, the control unit 3 accumulates the inducement parameter in the data accumulation unit 171, and the inducement parameter used in the manufacturing unit 2 is brought closer to the manufacturing parameter at the time of initialization, or Change to manufacturing parameters (step 4).

That is, the manufacturing parameters of each process identified as trigger parameters are changed as follows.
In the electrode forming process, as manufacturing parameters, the environmental temperature, the environmental humidity, the kneading temperature and kneading humidity in the material container 40, the drive power when the drive motor 47 is driven, the rotation speed of the electric propeller section 46, and the viscosity of the electrode material. and bringing the identified trigger parameters of these manufacturing parameters closer to default settings or resetting them to default settings.
In the slurry forming step, manufacturing parameters include the temperature and humidity in the material container 40, the amount of power when the drive motor 47 is driven, the rotation speed of the electric propeller unit 46, and the viscosity of the electrode material. Bring the selected trigger parameters closer to their default settings or reset them to their default settings.
In the delivery process, manufacturing parameters include temperature and humidity in the cylinder part 55, drive power when the drive motor 57 is driven, rotation speed of the screw part 56, and viscosity of the electrode material. Bring the selected trigger parameters closer to their default settings, or restore them to their default settings.
In the coating process and the drying process, the manufacturing parameters include the environmental temperature, the environmental humidity, the opening widths of the discharge ports 61 and 61 of the kneading and coating devices 20 and 21, the coating speed, and the conveying rollers 66b of the kneading and coating devices 20 and 21. , 66d and the bottom of the presser roller 67, the drying temperature in the drying devices 34, 34 of the kneading and coating devices 20, 21, and the drying atmosphere, among these production parameters, specified contributors Move parameters closer to default or reset to default.
In the electrode rolling step, manufacturing parameters include environmental temperature, environmental humidity, spacing between the rolling rolls 70 and 71, rotational speed of the rolling rolls 70 and 71, electrode density after rolling, and thickness of the electrode layer 201. The specified trigger parameter among the parameters is brought closer to the initial setting or returned to the initial setting.
In the electrode forming process, as manufacturing parameters, the environmental temperature, the environmental humidity, the number of burrs generated on the electrode 210 (electrode 211) after cutting, the area of the burr, the position of the burr, the position of the connecting portion 205, and the area of the connecting portion 205 are set. and bringing the identified trigger parameters of these manufacturing parameters closer to default settings or resetting them to default settings. When the number of burrs generated on the electrode 210 (electrode 211) after cutting and the area of burrs are specified as trigger parameters, the cut portion of the punching device 80 corresponding to the burrs and the first cutting device 81 The cutting blade 90 and the cutting teeth 91 of the second cutting device 82 are replaced with new ones.
In the electrode body forming step, manufacturing parameters include environmental temperature, environmental humidity, contact area between the electrodes 210, 211 and the separator 212, the number of layers of the electrodes 210, 211 and the separator 212, and the number of layers of the electrodes 210, 211 and the separator 212. Trigger parameters identified among these manufacturing parameters, including the order, are brought closer to default settings or reset to default settings.
In the extraction electrode connection process, manufacturing parameters include environmental temperature, environmental humidity, welding temperature, welding pressure, holding time, and welding sensing time by the horn portions 116a and 116b. to the default settings or return to the default settings.
In the first laminating step, the manufacturing parameters include environmental temperature, environmental humidity, welding temperature of the welded parts 137, 138, welding pressure of the welded parts 137, 138, welding time of the welded parts 137, 138, welding sensing timing, Identified trigger parameters among these manufacturing parameters are brought closer to default settings or reset to default settings.
In the vacuum drying process, the manufacturing parameters include the drying temperature, drying humidity, vacuum degree, and power consumption of the vacuum pump 148 in the vacuum drying chamber 140, and among these manufacturing parameters, the specified trigger parameter is brought closer to the initial setting. or reset to default.
In the injection process, the production parameters include environmental temperature, environmental humidity, injection amount of the electrolytic solution 215, and concentration of the electrolytic solution 215, and among these production parameters, the specified trigger parameter is brought closer to the initial setting or is set to the initial setting. back to
In the second lamination step, the manufacturing parameters include environmental temperature, environmental humidity, welding temperature of the welding part 160, welding pressure of the welding part 160, welding time of the welding part 160, and welding sensing timing. The identified trigger parameters are brought closer to default settings or reset to default settings.

As shown in FIG. 14(b), the ratio of secondary batteries 200 whose quality is equal to or higher than a predetermined standard in the secondary battery group (hatched portion S in FIG. 14) When the ratio of those falling within the range exceeds a predetermined threshold value, it is determined that the quality of the secondary battery 200 satisfies a predetermined standard, and subsequent manufacturing in the manufacturing department 2 continues manufacturing while maintaining each manufacturing parameter.

Next, the deep learning unit 170 of this embodiment will be described.

The deep learning unit 170 of the present embodiment is composed of an arithmetic unit, a memory, and the like that realize a neural network incorporating a neuron model as shown in FIG. 15(a) as an approximation algorithm of the value function.
That is, as shown in FIG. 15(a), a neuron outputs an output y for m inputs x _i (i is a positive integer), and each x _i corresponds to this input x _i It is multiplied by the weight wi and outputs an output _y expressed by the following equation (1). Note that the inputs x _i , outputs y, and weights w _i are all vectors.

where b is the bias and f is the activation function.

The neural network of the deep learning unit 170 of this embodiment includes an input layer 180, an intermediate layer 181, and an output layer 182, as shown in FIG. 15(b). ) and has a thickness of p layers (p is a positive integer of 4 or more). That is, the intermediate layer 181 has p-layer intermediate layers D1 to Dp.
The neural network of this embodiment receives S inputs X (X ₁ to X _S : S is a positive integer) from the input layer 180, passes through the intermediate layer 181, and outputs T results Y (Y ₁ to Y _T : T is a positive integer) is output.

Specifically, the input X (X ₁ to X _S ) of the input layer 180 is multiplied by the corresponding weight W1 and input to each neuron N1 of the first intermediate layer D1 of the intermediate layer 181 . Each neuron N1 of the first hidden layer D1 outputs a feature vector Z1, and the feature vector Z1 is input to each neuron N2 of the second hidden layer D2 of the hidden layer 181 after being multiplied by a corresponding weight W2. be.

The feature vector Z1 is a feature vector between the weight W1 and the weight W2, and can be regarded as a vector obtained by extracting the feature amount of the input vector.
The feature vector Z1 is input to each neuron N2 of the second intermediate layer D2 of the intermediate layer 181 after being multiplied by the corresponding weight W2.
Each neuron N2 of the second hidden layer D2 outputs a feature vector Z2, and the feature vector Z2 is input to each neuron N3 of the third hidden layer D3 of the hidden layer 181 after being multiplied by a corresponding weight W3. be.
The above processing is repeated in each intermediate layer of the intermediate layer 181 , and the neuron Np of the terminal P-th intermediate layer Dp outputs the feature vector Zp, and the feature vector Zp is output to the output layer 182 . As a result, the neural network outputs results Y (Y ₁ to Y _T ).
The weights W1 to Wp can be learned by the error backpropagation method. The error backpropagation method is a method of adjusting (learning) the weight W of each neuron so as to reduce the difference between the output y when the input x is input and the true output y (teacher). .

Next, an example of the secondary battery 200 manufactured by the secondary battery manufacturing system 1 of this embodiment will be described.

The secondary battery 200 is a so-called laminated secondary battery in which electrodes 210 and 211 and a separator 212 are laminated as shown in FIG. 16, and uses metal ions as carriers. The tab electrode members 213 and 214, which are lead electrodes, protrude from one side of the member).
The secondary battery 200 of the present embodiment is a non-aqueous electrolyte secondary battery, specifically a lithium ion secondary battery using a non-electrolyte as an electrolyte.
The secondary battery 200 includes a positive electrode 210 , a negative electrode 211 , a separator 212 , tab electrode members 213 and 214 (extracting electrodes), an electrolytic solution 215 and an enclosure 216 .

The positive electrode 210 is obtained by laminating a positive electrode layer 201 a on at least one side of the metal foil 202 . In the positive electrode 210 of this embodiment, positive electrode layers 201a, 201a are laminated on both sides of a metal foil 202. As shown in FIG.
The positive electrode 210 has a connecting portion 205 a that is able to be connected to the tab electrode member 213 by a part of the metal foil 202 projecting more planarly than the other part.

The negative electrode 211 is formed by forming a negative electrode layer 201b on at least one side of the metal foil 202 . In the negative electrode 211 of the present embodiment, negative electrode layers 201b and 201b are laminated on both sides of the metal foil 202 .
The negative electrode 211 has a connecting portion 205 b that is able to be connected to the tab electrode member 214 by a part of the metal foil 202 projecting more planarly than the other part.

The separator 212 is a member that separates the positive electrode 210 and the negative electrode 211 to prevent a short circuit, and is a member that retains the electrolyte 215 to ensure metal ion conductivity.
The tab electrode member 213 is a member that extracts electrons from the positive electrode 210 during charging and injects electrons into the positive electrode 210 during discharging.
The tab electrode member 214 is a member that injects electrons into the negative electrode 211 during charging and extracts electrons from the negative electrode 211 during discharging.

The electrolytic solution 215 functions as an electrolyte, and is a non-aqueous electrolytic solution that does not substantially contain water in this embodiment.
The enclosure 216 is a member that encloses the positive electrode 210 , the negative electrode 211 , the separator 212 , the electrolytic solution 215 , and part of the tab electrode members 213 and 214 , and is formed of laminate films 230 and 231 .

In the secondary battery 200, a positive electrode 210, a separator 212, a negative electrode 211, and a separator 212 are stacked in multiple layers in this order, and the separator 212 is positioned on the outermost side (on the enclosure 216 side) in the stacking direction.
The connecting portions 205a of the positive electrodes 210 overlap each other when viewed from above, and the tab electrode member 213 is connected to the overlapping portion.
Similarly, the connecting portions 205b of the negative electrodes 211 overlap when viewed from above, and the tab electrode member 214 is connected to the overlapping portion.
The enclosure 216 is hermetically sealed and substantially air-free.

According to the secondary battery manufacturing system 1 of the present embodiment, when the quality of the secondary battery 200 in the secondary battery group manufactured by the manufacturing unit 2 falls below a predetermined standard, the deep learning unit 170 An incentive parameter that induces quality deterioration is specified from 200 manufacturing parameters, and the incentive parameter is brought closer to the parameter at the time of initial setting. Therefore, after that, the quality of the secondary battery group manufactured by the manufacturing department 2 can be improved, and the secondary batteries 200 of a certain quality or higher can be continuously manufactured.

In the above-described embodiment, each manufacturing process in the manufacturing department 2 was performed automatically, but the present invention is not limited to this. A part of each manufacturing process in the manufacturing department 2 may be performed manually.

In the above-described embodiment, the secondary battery manufacturing system 1 is used to manufacture the secondary battery 200 having a laminated structure, but the present invention is not limited to this. A secondary battery 200 having a wound structure may be manufactured. In this case, the electrode stacking device 6 serves as an electrode winding device for winding the electrode body 218 .

In the above-described embodiment, the tab electrode members 213 and 214 protrude from one side of the enclosure 216, but the present invention is not limited to this. It does not matter where the tab electrode members 213 and 214 protrude from the enclosure 216 . For example, a structure in which the tab electrode members 213 and 214 protrude from two opposite sides of the enclosure 216 may be employed.

In the embodiment described above, the secondary battery manufacturing system 1 includes one manufacturing unit 2, but the present invention is not limited to this. The secondary battery manufacturing system 1 may include two or more manufacturing departments 2 .

In the above-described embodiment, the case of using a lithium ion secondary battery as the secondary battery 200 has been described, but the present invention is not limited to this. A monovalent battery such as a sodium ion secondary battery or a potassium ion secondary battery, a multivalent ion battery such as a magnesium ion secondary battery, or other secondary batteries such as an air battery may be used.

In the above-described embodiment, the number of laminated layers of each of the electrodes 210 and 211 of the electrode body 218 is three, but the present invention is not limited to this. The number of laminated electrodes 210 and 211 constituting the electrode body 218 may be one or two, or may be four or more.

In the embodiment described above, the separator 212 is positioned on the outermost side in the stacking direction of the electrode body 218, but the present invention is not limited to this. The electrodes 210 and 211 may be positioned on the outermost side of the electrode body 218 in the stacking direction.

In the embodiment described above, the deep learning unit 170 performs supervised learning, but the present invention is not limited to this. Semi-supervised learning may be performed in which only a part of the input and output data pairs exist and the other part is input data only and machine learning is performed. Also, unsupervised learning and reinforcement learning may be performed as necessary.

In the above-described embodiment, the case of the deep learning unit 170 that learns according to the algorithm of a deep neural network with four or more layers as the machine learning unit has been described, but the present invention is not limited to this. Learning may be performed according to a neural network algorithm of three layers or less.

In the embodiment described above, the kneading and coating devices 20 and 21 of the manufacturing section 2 are provided in the manufacturing room, but the present invention is not limited to this. The kneading and coating devices 20 and 21 of the manufacturing department 2 may also be provided in the dry room like the other devices.

1 Secondary Battery Manufacturing System 2 Manufacturing Department 3 Control Department 4 Evaluation Department 5, 5a, 5b Electrode Forming Device 6 Electrode Laminating Device 7 Welding Device 8 Sealing Device 11 Electrical Characteristic Evaluation Device 12 Resistance Characteristic Evaluation Device 13 Shape Evaluation Device 14 Structure Evaluation device 20 First kneading and coating device 21 Second kneading and coating device 22 Press device 23 Forming device 46 Electric propeller section 47 Drive motor 55 Cylinder section 70, 71 Rolling roll 80 Punching device 81 First dividing device 82 Second dividing Device 90 Separating blade (cutting part)
91 parting tooth (cutting part)
100, 101 electrode transfer line 102 separator transfer line 105 cell transfer line 116a, 116b horn portion 130 first welding device 131 vacuum drying device 132 electrolytic solution injection device 133 second welding device 135, 136 welding members 137, 138 welding portion 140 vacuum Drying chambers 148, 161 Vacuum pump 160 Welding unit 170 Deep learning unit (machine learning unit)
171 data storage unit (storage unit)
172 Evaluation result acquiring unit 173 Judging unit 180 Input layer 181 Intermediate layer 182 Output layer 200 Secondary battery 201a Positive electrode layer 201b Negative electrode layer 202 Metal foils 205, 205a, 205b Connecting portion 210 Positive electrode (electrode)
211 negative electrode (electrode)
212 Separator 213, 214 Tab electrode member 215 Electrolytic solution 216 Enclosure (sealing member)
218 electrode body 230, 231 laminate film

Claims (10)

A control unit, a manufacturing unit that automatically performs part or all of the manufacturing process of a secondary battery, and an evaluation unit that evaluates the quality of the secondary battery manufactured by the manufacturing unit,
The control unit has a storage unit and a machine learning unit, and is capable of controlling manufacturing parameters used for manufacturing in the manufacturing unit,
The storage unit associates and stores current and past manufacturing parameters and evaluation results of secondary batteries manufactured using the past manufacturing parameters by the evaluation unit,
The control unit determines whether the quality of the secondary battery has deteriorated below a predetermined standard, and if it is determined that the quality of the secondary battery manufactured by the manufacturing unit has deteriorated below the predetermined standard. (2) specifying an inducement parameter that affects quality deterioration from among the manufacturing parameters based on the relationship between the past manufacturing parameters and the past evaluation results stored in the storage unit, and setting the inducement parameter as the manufacturing parameter at the time of initial setting; A control method for a secondary battery manufacturing system, characterized by returning to Simultaneously or continuously manufacturing multiple secondary batteries,
A predetermined number of secondary batteries are extracted from the plurality of secondary batteries, and if a ratio of secondary batteries whose quality is within a predetermined range among the predetermined number of secondary batteries is below a predetermined threshold, the machine learning unit 2. The method of controlling a secondary battery manufacturing system according to claim 1, wherein the step determines that the quality of the secondary battery has deteriorated. The manufacturing process of the secondary battery includes at least a slurry forming process, a coating process, an electrode body forming process, and an extraction electrode connecting process,
The slurry forming step is a step of kneading at least an electrode active material, a solvent and a binder with an electric propeller to form a slurry electrode material,
The coating step is a step of applying the slurry electrode material to a metal foil and drying it to form an electrode,
The electrode body forming step is a step of forming an electrode body by stacking the electrode and the separator,
The extraction electrode connecting step is a step of connecting the extraction electrode to the electrode body by welding,
3. The method of controlling a secondary battery manufacturing system according to claim 1, wherein the manufacturing parameters include parameters (1) to (4) below.
(1) At least one parameter selected from kneading temperature, environmental temperature, environmental humidity, viscosity of electrode material, number of revolutions of electric propeller, and driving power of electric propeller in the slurry forming step.
(2) At least one parameter selected from environmental temperature, environmental humidity, viscosity of the electrode material, coating speed, electrode thickness, drying temperature, and drying atmosphere in the coating step.
(3) At least one parameter selected from environmental temperature, environmental humidity, contact area between electrodes and separators, number of overlapping electrodes and separators, and overlapping order of electrodes and separators in the electrode body forming step.
(4) At least one parameter selected from environmental temperature, environmental humidity, welding temperature, welding pressure, holding time, and welding sensing timing in the extraction electrode connecting step. The manufacturing process of the secondary battery includes an electrode forming step in which the electrode is cut by a cutting part of an electrode cutting machine and the shape of the electrode is adjusted,
4. The method of controlling a secondary battery manufacturing system according to claim 3, wherein the manufacturing parameters include the following parameters (5).
(5) At least one parameter selected from environmental temperature, environmental humidity, the number of burrs generated on the electrode after cutting, and the area of burrs on the electrode body after cutting in the electrode forming step. The manufacturing parameters include the number of burrs generated on the electrode after cutting in the electrode forming step or the area of burrs on the electrode body after cutting,
5. When the number of burrs generated on the electrode after cutting or the area of burrs on the electrode body after cutting is specified as the trigger parameter, the cutting portion of the electrode cutting machine is replaced with a new one. A control method for the described secondary battery manufacturing system. The manufacturing process of the secondary battery includes a vacuum drying process in which the electrode assembly is housed in a bag-shaped sealing member and dried while being vacuumed by a vacuum pump, and an electrolytic solution is injected into the sealing member. an electrolytic solution injection step of sealing by welding a part of the sealing member,
6. The method of controlling a secondary battery manufacturing system according to claim 3, wherein the manufacturing parameters include parameters (6) and (7) below.
(6) At least one parameter selected from drying temperature, drying humidity, degree of vacuum, and power consumption of a vacuum pump in the vacuum drying step.
(7) Environmental temperature, environmental humidity, welding temperature of the sealing member, welding pressure of the sealing member, welding time of the sealing member, sensing timing of the sealing member, and the electrolysis in the electrolytic solution injection step At least one parameter selected from the injection amount of the liquid and the concentration of the electrolyte. The manufacturing process of the secondary battery includes an electrode rolling process of rolling the electrode by sandwiching it between a pair of rolls,
7. The method of controlling a secondary battery manufacturing system according to any one of claims 3 to 6, wherein the manufacturing parameters include the following parameters (8).
(8) At least one parameter selected from environmental temperature, environmental humidity, rotation speed of the pair of rolls, gap between the pair of rolls, electrode density after rolling, and electrode thickness in the electrode rolling step. The manufacturing process of the secondary battery includes at least a slurry forming process, a coating process, and an electrode forming process including a rolling process,
The slurry forming step is a step of kneading at least an electrode active material, a solvent and a binder with an electric propeller to form a slurry electrode material,
The coating step is a step of applying the slurry electrode material to a metal foil and drying it to form an electrode,
The rolling step is a step of rolling the metal foil on which the electrodes are formed,
8. The method of controlling a secondary battery manufacturing system according to claim 1, wherein said electrode forming step is performed automatically. 9. The machine learning unit performs supervised learning, and learns the relationship between past manufacturing parameters and past evaluation results stored in the storage unit as teacher data. A control method for a secondary battery manufacturing system according to any one of 1. 10. The method of controlling a secondary battery manufacturing system according to any one of claims 1 to 9, wherein the machine learning unit is a deep learning unit that learns according to a neural network of four or more layers.

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