JP6149022B2 - How to replace the storage module - Google Patents

Description

  The present invention relates to a method for replacing a power storage module in which a plurality of power storage modules in which a plurality of storage batteries are stacked are provided and a temperature sensor is mounted on at least one set of the power storage modules.

  Generally, a power storage module in which a plurality of storage batteries (battery cells) are stacked is known. For example, since this power storage module is mounted on an electric vehicle such as a hybrid vehicle or an EV, a power storage device including a large number of sets of the power storage modules is configured.

  In this case, in the power storage device, when a decrease in the power generation performance of the storage battery is detected, an operation of replacing the storage module in which the storage battery having a defect is incorporated with a new or in-use storage module without a defect is performed. ing. In this case, the battery state diagnosis device for an assembled battery of Patent Document 1 has been proposed for the purpose of easily diagnosing the battery state of the assembled battery without much effort.

  The battery state diagnosis apparatus includes a no-load voltage calculation unit that calculates a no-load voltage of a unit battery, a first determination unit, and a second determination unit. The first determination means determines whether the battery state of each unit battery is normal or abnormal based on the unit battery no-load voltage calculated by the no-load voltage calculation means. The second determination unit determines that the module battery including the unit battery determined to be abnormal by the first determination unit is an abnormal module battery that needs to be replaced.

  Accordingly, it is automatically determined which of the module batteries constituting the assembled battery is abnormal. Thereby, it is said that the replacement operation of the abnormal module battery is greatly simplified as compared with the conventional method in which each of the module batteries is manually inspected.

JP-A-11-149944

  By the way, as for the storage battery apparatus, output control and temperature control are performed based on the temperature of a storage battery. This is because the storage battery needs to be temperature controlled because it easily deteriorates at a high temperature.

  On the other hand, the internal resistance of the storage battery is increased due to the period of use. For this reason, in the storage battery used over a predetermined period, the internal resistance is considerably increased, and the amount of heat generation is larger than that of the new storage battery, and the temperature is easily increased. Therefore, the temperature at the time of operation will fluctuate between a new module battery that has been replaced and another module battery that is being used.

  However, in said patent document 1, temperature management based on the replaced module battery and the other module battery currently used is not made | formed. Accordingly, when output control based on the temperature of a new module battery having a relatively low temperature is performed, there is a problem that other module batteries that are at a high temperature deteriorate.

  The present invention solves this type of problem, and provides a method for replacing a power storage module that can satisfactorily suppress deterioration due to a temperature difference between a replaced power storage module and a power storage module that is not replaced. Objective.

  The present invention relates to a method of replacing the power storage module in a power storage device including a plurality of power storage modules each having a plurality of storage batteries stacked and having a temperature sensor mounted on at least one set of the power storage modules.

The replacement method includes a replacement determination step for determining whether or not to replace a power storage module on which a temperature sensor is mounted, and replacing the power storage module determined to be replaced with another power storage module outside the power storage device. A storage module replacement step. In this replacement method, when the difference between the average value of the capacity deterioration of the replaced power storage module and the average value of the capacity deterioration of the other power storage modules is equal to or greater than a specified value , the temperature sensor is connected to the power storage module that is not replaced. Alternatively, when another temperature sensor is mounted as a replacement temperature sensor and the difference between the average value of the capacity deterioration of the replaced power storage module and the average value of the capacity deterioration of the other power storage module is less than the specified value, The power storage module includes a temperature sensor mounting step in which the temperature sensor or another temperature sensor is mounted as a replacement temperature sensor .

In this replacement method, when the replacement temperature sensor is mounted on the non- replaceable power storage module, the replacement temperature sensor is preferably mounted on the non-replaceable power storage module adjacent to the replaced power storage module.

  Further, in this replacement method, it is preferable that the replacement temperature sensor is mounted at the same position as the position of the temperature sensor mounted on the replaced power storage module.

According to the present invention, while the power storage module on which the temperature sensor is mounted is replaced , the difference between the average value of the capacity deterioration of the replaced power storage module and the average value of the capacity deterioration of the other power storage modules is equal to or greater than a specified value. In some cases, a temperature sensor is newly mounted on the power storage module that is not replaced. For this reason, output control and temperature control are performed based on the temperature of the power storage module that is not replaced and has a larger amount of heat generation than other power storage modules incorporated by replacement. Therefore, the storage module that is not replaced is not controlled at a temperature and output exceeding the control range, and the occurrence of deterioration can be suppressed as much as possible.

In addition , the exchanged power storage module and the non-exchanged power storage module can satisfactorily suppress deterioration due to a temperature difference, and a high-quality power storage device can be obtained through a simple process.

It is schematic structure explanatory drawing of the electrical storage apparatus with which the replacement | exchange method of the electrical storage module which concerns on embodiment of this invention is applied. It is a principal part disassembled perspective explanatory drawing of the said electrical storage module. It is a flowchart explaining the said exchange method. It is explanatory drawing of the capacity | capacitance degradation by a use period and a resistance raise. It is explanatory drawing of the temperature difference by a use period. It is explanatory drawing at the time of replacing | exchanging the electrical storage module with which the temperature sensor is mounted. It is explanatory drawing at the time of replacing | exchanging the electrical storage module in which a temperature sensor is not mounted.

  As shown in FIG. 1, a power storage device 10 to which a method for replacing a power storage module according to an embodiment of the present invention is mounted, for example, on an unillustrated hybrid vehicle or an electric vehicle such as an EV.

  The power storage device 10 includes a plurality of sets electrically connected in series, for example, four sets of power storage modules 12A, 12B, 12C, and 12D. In the power storage module 12A, a plurality of storage batteries (battery cells) 16 are stacked horizontally (or in the direction of gravity) between a pair of end plates 14a and 14b. As shown in FIG. 2, the storage battery 16 has a rectangular shape and is alternately stacked with separators (holders) 18 having insulating properties in a state of being placed in a standing posture.

  The storage battery 16 consists of a lithium ion battery, for example, and has a rectangle (or square). On the upper surface of each storage battery 16, a positive electrode (or negative electrode) terminal 20a and a negative electrode (or positive electrode) terminal 20b are provided. The terminals 20a and 20b of the storage batteries 16 adjacent to each other are electrically connected by a bus bar (not shown).

  The separator 18 is bent and formed in a wave shape along the vertical direction in a side view by bending the resin thin plate into a wave shape. This is because a cooling air passage is formed between the separator 18 and the storage battery 16. Each corner portion of the separator 18 is provided with a support portion 18 a that engages with each corner portion of the storage battery 16 and supports the storage battery 16. A pair of thermistor holding portions 18b and 18b projecting in one direction in the stacking direction are provided at the lower center of the separator 18.

  As shown in FIG. 1, in the power storage module 12 </ b> A, a temperature sensor, for example, a thermistor 22 is arranged corresponding to the storage battery 16 having the lowest temperature and the storage battery 16 having the highest temperature. Specifically, the thermistor holding portion 18b is provided on the separator 18 that supports the storage batteries 16 (a) and 16 (b) disposed at both ends in the stacking direction and the storage battery 16 (c) disposed in the center in the stacking direction. The thermistor 22 is attached via

  As shown in FIG. 2, the thermistor 22 includes a pair of elastic claws 22a and 22b that can be opened and closed by its own elasticity, and the elastic claws 22a and 22b engage with the thermistor holding portions 18b and 18b. As shown in FIG. 1, the thermistor 22 is connected to the controller 24 and sends detected temperature information to the controller 24.

  A voltage sensor 26A that detects a cell voltage of each storage battery 16 is connected to the storage module 12A. The voltage sensor 26 </ b> A constitutes a voltage sensing circuit, and sends each cell voltage to the controller 24.

  The power storage modules 12B, 12C, and 12D are configured in the same manner as the power storage module 12A described above, and the same components are denoted by the same reference numerals and detailed description thereof is omitted.

  The power storage module 12B is electrically connected in series with the power storage module 12A via the wiring 28a. A voltage sensor (voltage sensing circuit) 26 </ b> B that detects the cell voltage of each storage battery 16 is connected to the controller 24.

  The power storage module 12C is electrically connected in series with the power storage module 12B via the wiring 28b. A voltage sensor (voltage sensing circuit) 26 </ b> C that detects the cell voltage of each storage battery 16 is connected to the controller 24.

  The power storage module 12D is electrically connected in series with the power storage module 12C via the wiring 28c. A voltage sensor (voltage sensing circuit) 26 </ b> D that detects the cell voltage of each storage battery 16 is connected to the controller 24. Note that the thermistor 22 may be disposed in at least one of the power storage modules 12B, 12C, and 12D.

  In the power storage device 10 configured as described above, a method for replacing the power storage module according to the present embodiment will be described below along the flowchart shown in FIG.

  First, in step S1, it is determined whether or not the power storage modules need to be replaced in the power storage modules 12A to 12D. Specifically, the capacity deterioration of each storage battery 16 constituting the power storage modules 12A to 12D is detected. As shown in FIG. 4, the capacity of the storage battery 16 has deteriorated due to the number of years used, and when the capacity falls below a predetermined specified value, that is, a deterioration threshold value or less, it is determined that the storage battery 16 needs to be replaced. Is done. The capacity can be detected, for example, by fully discharging the storage battery 16 and then measuring the amount of discharge.

  In step S1, it is determined whether or not the resistance value (internal resistance) of the storage battery 16 is equal to or higher than the rising threshold value. As shown in FIG. 4, the storage battery 16 has a resistance value that increases depending on the number of years of use. When the resistance value exceeds a predetermined specified value, that is, an increase threshold value, the storage battery 16 needs to be replaced. It is judged. The resistance value can be detected by using a known measuring device. Alternatively, the resistance can be detected by obtaining the slope of the IV characteristic graph.

  Furthermore, in step S1, it is determined in each storage battery 16 whether the temperature difference between the maximum temperature and the minimum temperature is equal to or greater than a temperature difference threshold value. As shown in FIG. 5, the storage battery 16 has a large temperature difference depending on the number of years used, and when this temperature difference exceeds a predetermined specified value, that is, a temperature difference threshold value, the storage battery 16 needs to be replaced. It is judged that there is.

  And when it is judged that the capacity | capacitance of any storage battery 16 is below a degradation threshold value, when it is judged that the resistance value of any storage battery 16 is more than an raise threshold value, or the maximum temperature and minimum temperature Is determined to be greater than or equal to the temperature difference threshold, it is determined that there is a storage module that requires replacement.

  If it is determined that there is a power storage module requiring replacement (YES in step S1), the process proceeds to step S2, and it is determined whether or not the power storage module requiring replacement is a power storage module 12A on which the thermistor 22 is mounted ( Exchange judgment process). When it is determined that the power storage module requiring replacement is the power storage module 12A (YES in step S2), the process proceeds to step S3, where the power storage module 12A and the new power storage module 12Aa are replaced (power storage module replacement step). (See FIG. 6).

  In step S4, it is determined whether the position of the thermistor 22 is mounted on a new power storage module 12Aa or a power storage module 12B (or power storage module 12C or power storage module 12D) that is not replaced.

  In this step S4, for example, the average value of capacity deterioration (%) of the power storage module 12A taken out by replacement is compared with the average value of capacity deterioration of the new power storage module 12Aa incorporated by replacement. When it is determined that the difference between the average values is equal to or greater than the specified value and the thermistor position needs to be changed (YES in step S4), the process proceeds to step S5, and the placement work of the thermistor 22 as the replacement temperature sensor is performed. (Temperature sensor mounting process).

  Specifically, as shown in FIG. 6, the thermistor 22 is placed in the same arrangement position as the arrangement position of the thermistor 22 mounted on the electricity storage module 12 </ b> A in the electricity storage module 12 </ b> B that is not exchanged adjacent to the exchanged electricity storage module 12 </ b> A. Is installed. On the other hand, the thermistor 22 is not mounted on the replaced new power storage module 12Aa.

  As the thermistor 22 mounted on the power storage module 12B, the thermistor 22 mounted on the replaced power storage module 12A may be used, or a new thermistor 22 may be used.

  By the way, when the new power storage module 12Aa is not a new one and is mounted and used in another fuel cell electric vehicle, the storage battery 16 has been deteriorated. For this reason, in the power storage module 12Aa, the difference in the average value of capacity deterioration from the power storage module 12A is less than the specified value, and the thermistor position change is not required (NO in step S4). Therefore, proceeding to step S6, the thermistor 22 mounted on the power storage module 12A or another thermistor 22 is mounted on the new power storage module 12Aa at the same arrangement position as the replaced power storage module 12A. The

In this case, in this embodiment, the power storage module 12A on which the thermistor 22 is mounted is replaced with another power storage module 12Aa, while the thermistor 22 or a new thermistor 22 is mounted on the power storage module 12B that is not replaced. Yes. This makes it possible to perform output control and temperature control based on the temperature of the power storage module 12B that is not replaced and has a larger amount of heat generation than the power storage module 12Aa incorporated by replacement.

  For this reason, the storage module 12B that is not replaced is not controlled at a temperature and output that exceed the control range, and the occurrence of deterioration can be suppressed as much as possible.

  Therefore, the replaced power storage module 12Aa and the non-replaced power storage module 12B (12C and 12D) can favorably suppress deterioration due to a temperature difference. Thereby, the effect that the high-quality electrical storage apparatus 10 can be obtained reliably with a simple process is acquired.

  Next, when it is determined in step S2 that the replacement power storage module is not mounted with the thermistor 22, for example, the power storage module 12B, the process proceeds to step S7. In step S7, as shown in FIG. 7, a new power storage module 12Ba is incorporated in place of the power storage module 12B (power storage module replacement step).

  And it progresses to step S8 and the thermistor 22 corresponding to the predetermined storage battery 16, for example, the outer storage battery 16 (d), is mounted on the replaced power storage module 12Ba (temperature sensor mounting step).

  Thus, in the present embodiment, the temperature of the power storage module 12Ba is less likely to increase than that of the other power storage modules 12A. For this reason, when output control is performed based on the temperature information of the power storage module 12A, the power storage module 12Ba outputs excessively at a low temperature, and deterioration is likely to occur. For this reason, by acquiring and controlling the temperature information of the power storage module 12Ba, it is possible to prevent the power storage module 12Ba from outputting excessively at low temperatures. Thereby, the effect that it becomes possible to prevent degradation of electrical storage module 12Ba as much as possible is acquired.

  When the internal resistance (deterioration degree) of the replaced power storage module 12Ba is larger than the internal resistance of the power storage module 12A, it is not necessary to provide the thermistor 22 in the power storage module 12Ba. Since the heat storage amount of the power storage module 12Ba having a high internal resistance is higher, the deterioration phenomenon as described above can be prevented by controlling the temperature based on the temperature of the thermistor 22 provided in the power storage module 12A as before the replacement. Because you can.

DESCRIPTION OF SYMBOLS 10 ... Power storage device 12A, 12Aa, 12B, 12Ba, 12C, 12D ... Power storage module 16 ... Storage battery 18 ... Separator 22 ... Thermistor 24 ... Controller 26A-26D ... Voltage sensor

Claims (3)

Replacing a power storage module including a plurality of power storage modules in which a plurality of storage batteries are stacked and replacing the power storage module in which the temperature sensor is mounted in a power storage device in which the temperature sensor is mounted in at least one set of the power storage modules A method,
A replacement determination step of determining whether to replace the power storage module on which the temperature sensor is mounted;
A power storage module replacement step of replacing the power storage module determined to be replaced with another power storage module outside the power storage device;
When the difference between the average value of the capacity deterioration of the replaced power storage module and the average value of the capacity deterioration of the other power storage module is equal to or greater than a specified value , the temperature sensor or another When the temperature sensor is mounted as a replacement temperature sensor and the difference between the average value of capacity deterioration of the replaced power storage module and the average value of capacity deterioration of the other power storage module is less than a specified value, A temperature sensor mounting step of mounting the temperature sensor or the other temperature sensor as the replacement temperature sensor on a power storage module ;
A method for replacing a power storage module, comprising: 2. The replacement method according to claim 1 , wherein when the replacement temperature sensor is mounted on the power storage module that is not replaced, the replacement temperature sensor is mounted on the power storage module that is not replaced adjacent to the replaced power storage module. A method for replacing a power storage module characterized by the above.   3. The replacement method according to claim 2, wherein the replacement temperature sensor is mounted at the same position as the position of the temperature sensor mounted on the replaced power storage module. method of exchange.

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