CN112582717A

CN112582717A - Battery with a battery cell

Info

Publication number: CN112582717A
Application number: CN202011438100.4A
Authority: CN
Inventors: 王辰云
Original assignee: Ningde Amperex Technology Ltd
Current assignee: Ningde Amperex Technology Ltd
Priority date: 2020-12-07
Filing date: 2020-12-07
Publication date: 2021-03-30

Abstract

The embodiment of the invention relates to the technical field of batteries, and discloses a battery which comprises a battery cell and a shell for accommodating the battery cell, wherein the battery cell comprises an electrode assembly, a first lug and a second lug, the first lug and the second lug are both arranged on the side surface of the electrode assembly, and an elastomer prepared by curing gel is arranged between the side surface of the electrode assembly and the shell. Thus, the electrode assembly is held by the elastic body holder. In the process of vibrating or falling the battery, the gravity impulse of the electrode assembly can be buffered by the elastic body, so that the electrode assembly cannot be displaced, and further, the first lug and the second lug cannot be pulled by the electrode assembly to break or fall off, and the battery has better vibration and falling resistance. In addition, the elastomer is made by curing gel, so that the elastomer is convenient to mount and position and simple to operate.

Description

Battery with a battery cell

Technical Field

The embodiment of the invention relates to the technical field of batteries, in particular to a battery.

Background

The existing battery can be divided into two types of winding type and lamination type, and comprises a shell, an electric core and electrolyte, wherein the electric core and the electrolyte are packaged in the shell, the electric core comprises an electrode assembly, a first tab and a second tab, the first tab and the second tab are connected with the electrode assembly, a gap is reserved between the side face of the electrode assembly and the shell so as to facilitate the electrolyte to infiltrate the electrode assembly, and the first tab and the second tab are respectively arranged on the side face of the electrode assembly and are connected with the shell to form an output electric quantity terminal.

Based on the battery structure, the first lug and the second lug are not buffered by impulse in a vibration test or a drop test of the battery, so that the first lug and the second lug are easily broken or torn and stripped from the shell, and the battery is damaged. The existing solution is to stick double-sided adhesive tape on the surface of the battery core to bond and fix the shell and the battery core, however, in this solution, on one hand, the energy density of the battery is reduced, and on the other hand, the problem that the first tab and the second tab fall off and peel off cannot be thoroughly solved.

Disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a battery, in which an electrode assembly and tabs are stable and have good vibration and drop resistance.

In order to solve the above technical problem, an embodiment of the present invention provides a battery, including a battery cell and a casing accommodating the battery cell, where the battery cell includes an electrode assembly, a first tab and a second tab, the first tab and the second tab are both disposed on a side surface of the electrode assembly, and an elastic body is disposed between the side surface of the electrode assembly and the casing, and the elastic body is made by curing gel.

In some embodiments, the elastomer includes a plurality of interconnected pores that serve as flow channels for the electrolyte.

In some embodiments, the elastomer is made by curing a gel, wherein the gel comprises a polymer and a pore former for forming the micropores during curing of the gel.

In some embodiments, the weight percentage of the polymer is 20% to 80%, and the weight percentage of the pore former is 80% to 20%.

In some embodiments, the weight percentage of the polymer is 50% to 60% and the weight percentage of the pore former is 40% to 50%.

In some embodiments, the polymer comprises at least one of polypropylene, polyethylene, polyvinyl alcohol, polymethylmethacrylate, polyvinylidene fluoride, polyvinylidene chloride, polyvinylidene fluoride hexafluoropropylene, polyvinyl chloride, polyoxyethylene, polyethylene glycol, polyvinyl acetal, polyacrylonitrile, polyoxypropylene, and polypropylene oxide.

In some embodiments, the pore former comprises at least one of propylene carbonate, dimethylformamide, nitrogen methyl pyrrolidone, dibutyl phthalate, triethylene glycol dimethyl ether, and polyvinylpyrrolidone.

In some embodiments, the surface of the elastomer has tackiness to create adhesion to the electrode assembly.

In some embodiments, a side surface of the case is provided with a liquid injection port, and a gap between the liquid injection port and a side surface of the electrode assembly is not provided with the elastic body.

In some embodiments, the width of the liquid injection port is 3mm to 10 mm.

The embodiment of the invention has the following beneficial effects: in contrast to the prior art, an embodiment of the present invention provides a battery, which includes a battery cell and a casing accommodating the battery cell, where the battery cell includes an electrode assembly, a first tab and a second tab, the first tab and the second tab are both disposed on a side surface of the electrode assembly, and an elastic body made of gel curing is disposed between the side surface of the electrode assembly and the casing. Thus, the electrode assembly is held by the elastic body holder. In the process of vibration or falling of the battery, the gravity impulse of the electrode assembly can be buffered by the elastic body, so that the electrode assembly cannot be displaced, and further, the first lug and the second lug cannot be pulled by the electrode assembly to break or fall off, and therefore, the battery has better vibration and falling resistance. In addition, the elastomer is made by gel curing, the elastomer is convenient to install and position, and the manufacturing process is simple.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 is a schematic cross-sectional view of a battery according to an embodiment of the present invention;

fig. 2 is a front view of the internal structure of the battery shown in fig. 1;

fig. 3 is a front view showing an internal structure of a battery according to another embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of the battery shown in FIG. 3;

fig. 5 is an internal structural view of a battery according to another embodiment of the present invention;

FIG. 6 is a schematic cross-sectional view of the cell shown in FIG. 5;

FIG. 7 is a schematic diagram of an impregnated gel of a battery according to one embodiment of the present invention;

fig. 8 is a schematic view of the internal structure of the battery shown in fig. 7;

fig. 9 is a schematic cross-sectional structure of the battery shown in fig. 7;

fig. 10 is a front view showing an internal structure of a battery according to another embodiment of the present invention;

fig. 11 is a schematic cross-sectional structure view of the battery shown in fig. 10.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It should be noted that, if not conflicted, the various features of the embodiments of the invention may be combined with each other within the scope of protection of the present application. Additionally, while functional block divisions are performed in apparatus schematics, with logical sequences shown in flowcharts, in some cases, steps shown or described may be performed in sequences other than block divisions in apparatus or flowcharts. Further, the terms "first," "second," "third," and the like, as used herein, do not limit the data and the execution order, but merely distinguish the same items or similar items having substantially the same functions and actions.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1, a battery 10 according to a first embodiment of the present invention includes a battery cell 11, an electrolyte, and a casing 12 accommodating the battery cell 11 and the electrolyte, where the battery cell 11 includes an electrode assembly 13, a first tab 14, and a second tab 15. The first tab 14 and the second tab 15 are disposed on any one or two of the four side surfaces 134 of the electrode assembly 13, wherein the first tab 14 is connected to the first pole 121 on the casing 12, and the second tab 15 is connected to the second pole 122 on the casing 12. It is understood that when the housing 12 is a metal housing, one of the first tab 14 and the second tab 15 may also be directly connected to the metal housing. The first tab 14 may be a positive tab, and the second tab 15 is a negative tab; accordingly, the first tab 14 may be a negative tab and the second tab 15 may be a positive tab. In the following description, the first tab 14 is taken as a positive tab, and the second tab 15 is taken as a negative tab.

The electrode assembly 13 includes at least one first pole piece 131, at least one second pole piece 132, and at least one separator 133. Fig. 1 shows a structure of an electrode assembly in which the electrode assembly is a winding type, and in the structure shown in fig. 1, an electrode assembly 13 includes first and

second pole pieces

131 and 132 and a separator 133, wherein the first and

second pole pieces

131 and 132 are alternately stacked, and the separator 133 is disposed between any adjacent first and

second pole pieces

131 and 132. Wherein, the first pole piece 131 can be a positive pole piece, and the second pole piece 132 is a negative pole piece; accordingly, the first pole piece 131 may be a negative pole piece, and the second pole piece 132 is a positive pole piece. For example, the first pole piece 131 is taken as a positive pole piece, and the second pole piece 132 is taken as a negative pole piece. It is understood that the number of the first pole piece 131 and the second pole piece 132 is not limited, and the first pole piece 131 and the second pole piece 132 may have 1 to 100 layers or more, and may have 20 to 50 layers.

It will be appreciated that the electrode assembly 13 may also be laminated, i.e. form a laminated cell. In order to make the electrolyte fully infiltrate the electrode assembly 13, a gap exists between the side 134 of the electrode assembly 13 and the case 12 during packaging, so that the electrolyte can flow through the gaps around and enter between the stacked layers of the electrode assembly 13, thereby achieving an infiltration effect.

In order to fix the electrode assembly 13, so as to prevent the first tab 14 and the second tab 15 from being pulled by the displacement of the electrode assembly 13, and the first tab 14 and the second tab 15 are broken or torn off from the case 12, and the battery is damaged, in this embodiment, referring to fig. 2, an elastic body 16 made of gel curing is disposed between the side 134 of the electrode assembly 13 and the case 12, that is, the elastic body 16 is located at the gap between the side 134 of the electrode assembly 13 and the case 12, and the electrode assembly 13 is clamped in the case 12. For example, the gel is injected between the side 134 of the electrode assembly 13 and the case 12, and cured at a high temperature to obtain the elastic body, so that the elastic body is installed and positioned in the gap, and the operation is simple.

It is understood that, in the example shown in fig. 2, when the elastic body 16 is not provided with a channel, the elastic body 16 does not completely fill the gap between the side 134 of the electrode assembly 13 and the case 12, and thus, the electrolyte does not affect the wetting of the electrode assembly 13. In other embodiments, if the elastic body 16 is provided with a channel for the electrolyte to flow through, the elastic body 16 may fill or partially fill the gap between the side 134 of the electrode assembly 13 and the case 12.

Because the electrode assembly 13 is supported by the elastic body 16, the battery 10 eliminates or weakens the relative impulse between the battery cell 11 and the casing 12 through the elastic body 16 in a shock test or a drop test, so that the electrode assembly 13, the first tab 14 and the second tab 15 can be kept stable, the first tab 14 and the second tab 15 can be effectively prevented from being pulled to break or fall off, and on the other hand, the problem of battery bulge caused by the displacement of the electrode assembly 13 is also eliminated.

It is understood that the elastic body may be disposed around the sides of the electrode assembly to sufficiently fix the electrode assembly against displacement, thereby performing a buffering function. When the first tab and the second tab are disposed on the same side a of the electrode assembly, the elastic bodies may be disposed on the side a and a side B opposite to the side a, respectively, so that the electrode assembly is clamped to play a role in buffering, thereby preventing the first tab and the second tab from being broken or falling off due to pulling. When the first tab and the second tab are respectively disposed on two opposite sides of the electrode assembly, for example, on the opposite sides a and B, the elastic bodies may be respectively disposed on the sides a and B, so that the electrode assembly may be engaged to play a role in buffering, thereby preventing the first tab and the second tab from being broken or separated due to pulling.

In addition, in this embodiment, the elastic body is disposed at the side of the electrode assembly, i.e., the upper and lower surfaces of the electrode assembly are free of the elastic body, so that a decrease in energy density due to an increase in the thickness of the battery can be effectively prevented.

In some embodiments, the elastic body includes a plurality of connected micropores, and the micropores are used as a flow channel for the electrolyte, so that the electrolyte can smoothly flow into the inside of the electrode assembly, and the effect of infiltrating the first pole piece, the second pole piece and the diaphragm is achieved.

In some embodiments, the gel includes a polymer and a pore former for forming the micropores during curing of the gel. By the mode, the manufacturing process of the elastomer is simple, and the elastomer with a plurality of communicated micropores can be formed by solidifying the polymer and the pore-forming agent.

Wherein, the polymer is the main framework of the elastomer, plays the role of mechanical buffering and bonding, has proper elasticity, strength and viscosity, and has stable physical and chemical properties in the electrolyte. In some embodiments, the polymer comprises at least one of polypropylene (PP), Polyethylene (PE), polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA), polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), polyvinylidene fluoride hexafluoropropylene (PVDF-HFP), polyvinyl chloride (PVC), polyethylene oxide (PEO), polyethylene glycol (PEG), polyvinyl acetal (PVB/PVFM), Polyacrylonitrile (PAN), polypropylene oxide (PPO), and polypropylene oxide (PPO). For example, the polymers include polyvinylidene fluoride and polyvinyl alcohol.

The polymer generates tackiness during heat curing, so that the surface of the elastic body has tackiness to generate adhesion to the electrode assembly, and thus, when the electrode assembly is inclined toward the side a during a shock test of the battery, not only does the elastic body disposed between the side a and the case serve as a cushion for the electrode assembly, but also the elastic body disposed between the side B opposite to the side a and the case serves as adhesive tension to the other side of the electrode assembly due to the adhesion. That is, the battery assembly is fixed by the support buffering and the adhesive stretching to offset the gravity impulse of the resistor assembly, and the first tab and the second tab are prevented from being broken or falling off due to the displacement.

The pore-forming agent is used for generating pores in the polymer, and a proper amount of the pore-forming agent and the polymer are uniformly mixed to form the gel. And heating and curing the gel, and volatilizing the pore-forming agent to form the holes. In some embodiments, the pore-forming agent comprises at least one of Propylene Carbonate (PC), Dimethylformamide (DMF), N-methyl pyrrolidone (NMP), dibutyl phthalate (DBP), triethylene glycol dimethyl ether (TEGDME), and polyvinylpyrrolidone (PVP). For example, the pore former may be dibutyl phthalate.

In some embodiments, the weight percentage of the polymer is 20% to 80%, and the weight percentage of the pore former is 80% to 20%. It is understood that the greater the weight percent of the pore former, the more micropores are formed, and the greater the weight percent of the polymer, the greater the strength of the elastomer. Specifically, the appropriate weight percentage can be selected according to actual requirements.

To balance the strength and the number of micropores of the elastomer, in some embodiments, the weight percentage of the polymer is 50% to 60% and the weight percentage of the pore former is 40% to 50%, such that the strength and the number of micropores of the elastomer are both satisfactory.

In order to facilitate the injection of the electrolyte, in some embodiments, the side surface of the case is provided with an injection port, and the gap between the injection port and the side surface of the electrode assembly is not provided with the elastic body, so that the three-dimensional space between the injection port and the electrode assembly can accommodate a certain amount of electrolyte, for example, 5% of the injection volume, which facilitates the injection and the circulation of the electrolyte to the inside of the entire case. On the other hand, annotate the liquid mouth and still make things convenient for syringe needle to get into the battery is inside pours into electrolyte.

In some implementations, the width of the liquid injection port is 3mm-10mm, so that different sizes of injection needles and injection amounts can be adapted.

In summary, in the present embodiment, the battery includes a battery cell and a casing accommodating the battery cell, the battery cell includes an electrode assembly, a first tab and a second tab, the first tab and the second tab are disposed on a side surface of the electrode assembly, and an elastic body is disposed between the side surface of the electrode assembly and the casing. Thus, the electrode assembly is held by the elastic body holder. In the process of vibration or falling of the battery, the gravity impulse of the electrode assembly can be buffered by the elastic body, so that the electrode assembly cannot be displaced, and further, the first lug and the second lug cannot be pulled by the electrode assembly to break or fall off, and therefore, the battery has better vibration and falling resistance.

The second embodiment of the present invention also provides a battery manufacturing method S20, including:

s21: installing a battery cell into a shell, wherein the battery cell comprises an electrode assembly, a first tab and a second tab, and the first tab and the second tab are both arranged on the side surface of the electrode assembly;

s22: and welding a first tab of the battery cell to a first pole column on the shell, and welding a second tab of the battery cell to a second pole column on the shell. When the shell is a metal shell, any one of the first pole lug and the second pole lug can be welded on the metal shell, and the other one of the first pole lug and the second pole lug can be welded on a pole insulated from the metal shell.

S23: an elastic body is disposed between the side of the electrode assembly and the case.

S24: and (3) filling electrolyte, standing, and enabling the electrolyte to flow into the battery cell and diffuse into the battery cell to achieve the effect of infiltrating the electrode assembly.

S25: and performing high-temperature high-pressure formation on the battery in the step S24, and fixing the battery core and the shell together by applying pressure extrusion during the high-temperature high-pressure formation.

S26: steps S24 and S25 are repeated to perform multiple injections until a preset amount of electrolyte is filled, and finally, the case is sealed, resulting in the battery of the above-described first embodiment.

The elastic body is positioned in a gap between the side surface of the electrode assembly and the shell and clamps the electrode assembly in the shell. It is understood that the elastic body does not completely fill the gap between the side of the electrode assembly and the case, and thus, does not affect the electrolyte injection and wetting of the electrode assembly.

Because the electrode assembly is supported by the elastic body, the battery eliminates or weakens the relative impulse between the battery core and the shell through the elastic body in a vibration test or a drop test, so that the electrode assembly, the first pole lug and the second pole lug can be kept stable, the first pole lug and the second pole lug can be effectively prevented from being broken or falling off due to the fact that the electrode assembly is pulled by the electrode assembly, and on the other hand, the problem of battery bulge caused by displacement of the electrode assembly is also solved.

In this embodiment, the elastic body is disposed between the side surface of the electrode assembly and the case, so that the electrode assembly is supported and fixed by the elastic body, and thus, in the process of vibration or drop of the battery, the gravity impulse of the electrode assembly is buffered by the elastic body, so that the electrode assembly does not shift, and further, the first tab and the second tab are not pulled by the electrode assembly to break or fall off, so that the battery has better vibration and drop resistance.

In some embodiments, the elastic body includes a plurality of connected micropores, and the micropores are used as a flow channel for the electrolyte, so that the electrolyte can smoothly flow into the inside of the electrode assembly, thereby achieving the effect of wetting the electrode assembly.

In some embodiments, the elastomer is made by curing a gel, wherein the gel comprises a polymer and a pore former for forming the micropores during curing of the gel. The step S23 specifically includes:

s231: and preparing a gel, wherein the gel comprises a polymer and a pore-forming agent, and the pore-forming agent is used for forming micropores in the process of curing the gel.

S232: injecting the gel in a fluid form, the injected gel being located at a gap between a side of the cell and the casing, wherein the gap may be completely filled or partially filled.

S233: and (5) carrying out vacuum high-temperature baking for removing water and pore-forming and forming.

In the high-temperature baking process, the pore-forming agent expands and volatilizes to the gel for pore-forming, and meanwhile, the polymer in the gel expands and forms at high temperature to form the elastic body with micropores. By the mode, the manufacturing process of the elastomer is simple, and the elastomer with a plurality of communicated micropores can be formed by solidifying the polymer and the pore-forming agent.

In some embodiments, the weight percentage of the polymer is 20% to 80%, and the weight percentage of the pore former is 80% to 20%. It is understood that the greater the weight percent of the pore former, the more micropores are formed, and the greater the weight percent of the polymer, the greater the strength of the elastomer. Specifically, the appropriate weight percentage can be selected according to actual requirements. To balance the strength and the number of micropores of the elastomer, in some embodiments, the weight percentage of the polymer is 50% to 60% and the weight percentage of the pore former is 40% to 50%, such that the strength and the number of micropores of the elastomer are both satisfactory.

In addition, in the subsequent step S25, when the high-temperature high-pressure formation is performed, the elastomer and the electrolyte generate adhesion at a high temperature, and the battery core and the casing are fixed together by the extrusion with the application of pressure during the high-temperature high-pressure formation.

In order to facilitate the subsequent injection of the electrolyte, in some embodiments, the side surface of the shell is provided with an injection port, and a space with the volume of > 5% of the injection amount is reserved between the injection port and the side surface of the electrode assembly, so that gel is not injected, and the later injection of the electrolyte is facilitated. The width of the liquid injection port is 3mm-10mm, so that the syringe needle can adapt to the injection needles with different specifications and injection amount.

In summary, in the process of the vibration or falling of the battery, the gravity impulse of the electrode assembly is buffered by the elastic body, so that the electrode assembly is not displaced, and further, the first tab and the second tab are not pulled by the electrode assembly to break or fall off. In addition, the micropores on the elastomer are beneficial to the electrolyte to better infiltrate the electrode assembly. And the manufacturing process of the battery is simple and convenient.

The third embodiment of the present application further provides a method for manufacturing a battery, which combines fig. 3 and fig. 4, and the method includes:

(1) negative tab 103 is laser welded to steel can 101, positive tab 104 is welded to the positive post of steel can 101 insulated from steel can 101, and wound electrode assembly 102 is encased in the steel can.

(2) Injecting a gel in a fluid form around the periphery of the side surface of the electrode assembly 102 by using a needle 106, wherein the gel comprises 30% of polyvinylidene fluoride by weight: 30% of polyoxyethylene: 40% dibutyl phthalate, no gel was present on the upper and lower surfaces of the electrode assembly 102, and the injected gel did not extend beyond the upper edge of the inner cavity of the steel can 101. The steel case 101 is provided with a liquid injection port 112, and no gel is injected into a space between the liquid injection port 112 and the electrode assembly 102, so that electrolyte can be injected later. Referring to fig. 3, the width of the liquid inlet is 8 mm.

(3) And the sealing cover is welded by laser, and the surface of the sealing cover is any surface on the long and wide plane of the steel shell.

(4) And (5) baking at high temperature in vacuum to remove water, and forming a hole in the gel. In the high-temperature baking process, the pore-forming agent expands and volatilizes to form pores on the gel, and the polymer expands and forms at high temperature to form the elastomer.

(5) And (3) filling electrolyte, standing for 24 hours at normal temperature or standing for 12 hours at 60 ℃ after filling, so that the electrolyte passes through the micropores of the elastomer and enters the battery cell to fully infiltrate the electrode assembly.

(6) The high temperature formation, the formation battery pressure is 1MPa, and the internal extrusion force of the steel shell 101 fixes the electrode assembly 102 and the steel shell 101 together. Also, during the high temperature formation process, the elastomer and the electrolyte develop adhesion.

The above steps (5) and (6) are repeated to perform a plurality of injections until a predetermined amount of electrolyte is filled, and finally, the steel case 101 is sealed to manufacture the battery in the present embodiment.

The structure of the battery in this embodiment in the manufacturing process is shown in fig. 3 and 4, and specifically includes: the gel electrolyte comprises a steel shell 101, a wound electrode assembly 102, a negative tab 103, a positive tab 104, gel 105, a gel injection needle 106, a diaphragm 107, a negative tab 108, a positive tab 109, micropores 110 in gel after high-temperature baking, 8mm width space glue-free 111 and a liquid injection port 112.

In this embodiment, the elastic bodies with the micropores are filled in the gaps between the side surfaces of the electrode assembly and the steel shell, so that the periphery of the electrode assembly can have a good buffering effect, the electrode assembly cannot be displaced, and the first tab and the second tab cannot be broken or fall off due to the pulling of the electrode assembly. In addition, the micropores on the elastomer are beneficial to the electrolyte to better infiltrate the electrode assembly. And the manufacturing process of the battery is simple and convenient.

The fourth embodiment of the present application further provides a method for manufacturing a battery, which combines fig. 5 and fig. 6, and the method includes:

(1) negative tab 203 is laser welded to steel can 201, positive tab 204 is welded to the positive post of steel can 201 insulated from steel can 201, and laminated electrode assembly 202 is encased in steel can 201.

(2) A fluid gel is injected around the periphery of the side of the electrode assembly 202 by using needles 206, and the weight ratio of the gel is 25% of polyvinylidene fluoride: 25% of polyvinyl alcohol: 50% propylene carbonate, no gel on the upper and lower surfaces of the electrode assembly 202, and the injected gel does not extend beyond the upper edge of the inner recess of the steel can 201. The steel shell 201 is provided with a liquid injection port 212, and no gel is injected into the space between the liquid injection port 212 and the electrode assembly 202, so that electrolyte can be injected later. Referring to fig. 5, the width of the liquid inlet is 5 mm.

(3) And the sealing cover is welded by laser, and the surface of the sealing cover is any surface on the long and wide plane of the steel shell 201.

(5) And (3) filling electrolyte, standing for 24 hours at normal temperature or 16 hours at 60 ℃ after filling, so that the electrolyte passes through the micropores of the elastomer and enters the battery cell to fully infiltrate the electrode assembly.

(6) The high temperature formation, the formation battery pressure is 1.2MPa, and the electrode assembly 202 and the steel shell 201 are fixed together by the internal extrusion force of the steel shell 201. Also, during the high temperature formation process, the elastomer and the electrolyte develop adhesion.

(7) The above steps (5) and (6) are repeated to perform a plurality of injections until a predetermined amount of electrolyte is filled, and finally, the steel case 201 is sealed to manufacture the battery in the present embodiment.

The structure of the battery in this embodiment in the manufacturing process is shown in fig. 5 and 6, and specifically includes a steel case 201, a laminated electrode assembly 202, a negative tab 203, a positive tab 204, a gel 205, a gel injection needle 206, a diaphragm 207, a negative tab 208, a positive tab 209, micropores 210 in the gel after high-temperature baking, a 5 mm-wide space without a gel injection 211, and a liquid injection port 212.

In this embodiment, the elastic bodies with the micropores are filled in the gaps between the side surfaces of the electrode assembly and the steel shell, so that the periphery of the electrode assembly can have a good buffering effect, the electrode assembly cannot shift, and further, the first tab and the second tab cannot be broken or fall off due to pulling of the electrode assembly, so that the battery has good vibration and fall resistance. In addition, based on the weight percentage of the pore-forming agent being 50%, the elastic body has more micropores, which is beneficial to the electrolyte to better infiltrate the electrode assembly.

The fifth embodiment of the present application further provides a method for manufacturing a battery, which, with reference to fig. 7 and 8, includes:

(1) the positive electrode tab 304 on one side of the electrode assembly 302 is laser welded to the aluminum case 301, the negative electrode tab 303 is welded to the negative electrode post of the aluminum case 301 insulated from the aluminum case 301, and the laminated electrode assembly 302 is incorporated into the aluminum case 301.

(2) As shown in fig. 7, a gel formed by injecting a fluid into the bottom and the top of the aluminum shell 301, wherein the weight ratio of the gel is 30% of polymethyl methacrylate: 30% of polyvinylidene fluoride: azomethylpyrrolidone 20%: 20% propylene carbonate, no gel was present on the upper and lower surfaces of the electrode assembly 302, and the injected gel did not extend beyond the upper edge of the inner well of the aluminum can 301. The aluminum case 301 is provided with a liquid injection port 312, and no gel is injected into a space between the liquid injection port 312 and the electrode assembly 302, so that electrolyte can be injected later. Referring to fig. 7 and 8, the width of the liquid inlet is 10 mm.

(3) The cover is welded by laser, and the cover surface is any surface on the long and wide plane of the aluminum shell 301.

(5) And (3) filling electrolyte, standing for 20 hours at normal temperature or 16 hours at 60 ℃ after liquid injection, so that the electrolyte passes through the micropores of the elastomer and enters the electrode assembly 302 to fully soak the electrode assembly.

(6) The high temperature formation, the cell pressure is 1.3MPa, and the electrode assembly 302 and the aluminum can 301 are fixed together by the extrusion force inside the can. Also, during the high temperature formation process, the elastomer and the electrolyte develop adhesion.

(7) The above steps (5) and (6) are repeated to perform multiple injections until a predetermined amount of electrolyte is filled, and finally, the aluminum case 301 is sealed to manufacture the battery in the present embodiment.

The structure of the battery in this embodiment in the manufacturing process is shown in fig. 7 to 9, and specifically includes an aluminum case 301, a laminated electrode assembly 302, a negative electrode tab 303, a positive electrode tab 304, a gel 305, a gel injection needle 306, a separation film 307, a negative electrode 308, a positive electrode 309, micropores 310 in the gel after high-temperature baking, a top cover 311, a liquid injection port 312, and a 10 mm-width space glue-free 312.

In this embodiment, the gaps between the opposite side surfaces of the electrode assembly provided with the tabs and the steel shell are filled with elastic bodies with micropores, so that the two ends of the electrode assembly are clamped and fixed, a good buffering effect can be achieved, the electrode assembly cannot shift, the first tabs and the second tabs cannot be pulled by the electrode assembly to break or fall, and the battery has good anti-vibration and drop performance.

The fifth embodiment of the present application further provides a method for manufacturing a battery, which, with reference to fig. 10 and 11, includes:

(1) negative tab 403 of electrode assembly 402 is laser welded to steel can 401, positive tab 404 is welded to a positive post on steel can 401 that is insulated from steel can 401, and laminated electrode assembly 402 is encased in steel can 401.

(2) Injecting a fluid gel around the sides of the electrode assembly 402, wherein the gel comprises 20% of polyvinylidene fluoride by weight: 35% of polyvinyl alcohol: propylene carbonate 45% without gel on the upper and lower surfaces of the electrode assembly 402, and the injected gel did not go beyond the upper edge of the inner pit of the steel can 401. The steel case 401 is provided with a liquid injection port 412, and no gel is injected into a space between the liquid injection port 412 and the electrode assembly 402, so that electrolyte can be injected later. Specifically, referring to fig. 10, the width of the liquid inlet 412 is 3 mm.

(3) And the cover is welded by laser, and the cover surface is any surface on the long and wide plane of the steel shell 401.

(5) And (3) filling electrolyte, standing for 24 hours at normal temperature or standing for 20 hours at 60 ℃ after filling, so that the electrolyte passes through the micropores of the elastomer and enters the battery cell to fully infiltrate the electrode assembly.

(6) The high temperature formation, the formation cell pressure is 1.0MPa, and the electrode assembly 402 and the steel can 401 are fixed together by the extrusion force inside the can. Also, during the high temperature formation process, the elastomer and the electrolyte develop adhesion.

(7) The above steps (5) and (6) are repeated to perform a plurality of injections until a predetermined amount of electrolyte is filled, and finally, the steel case 401 is sealed to manufacture the battery in this embodiment.

The structure of the battery in this embodiment in the manufacturing process is shown in fig. 10 and fig. 11, and specifically includes a steel case 401, a laminated electrode assembly 402, a negative electrode tab 403, a positive electrode tab 404, a gel 405, a gel injection needle 406, a separation film 407, a negative electrode 408, a positive electrode 409, micropores 410 in the gel after high-temperature baking, a 3 mm-wide space without glue injection 411, and a liquid injection port 412.

In this embodiment, the elastic bodies with the micropores are filled in the gaps between the side surfaces of the electrode assembly and the steel shell, so that the periphery of the electrode assembly can have a good buffering effect, the electrode assembly cannot shift, and further, the first tab and the second tab cannot be broken or fall off due to pulling of the electrode assembly, so that the battery has good vibration and fall resistance.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; within the idea of the invention, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery comprises a battery core and a shell for accommodating the battery core, wherein the battery core comprises an electrode assembly, a first electrode lug and a second electrode lug, and the first electrode lug and the second electrode lug are arranged on the side surface of the electrode assembly.

2. The battery of claim 1, wherein the elastomer comprises a plurality of interconnected pores, the pores serving as flow channels for the electrolyte.

3. The cell defined in claim 2, wherein the gel comprises a polymer and a pore former for forming the micropores during curing of the gel.

4. The battery of claim 3, wherein the polymer is present in an amount of 20-80% by weight and the pore former is present in an amount of 80-20% by weight.

5. The battery of claim 4, wherein the polymer is present in an amount of 50-60 wt% and the pore former is present in an amount of 40-50 wt%.

6. The battery of claim 3, wherein the polymer comprises at least one of polypropylene, polyethylene, polyvinyl alcohol, polymethyl methacrylate, polyvinylidene fluoride, polyvinylidene chloride, polyvinylidene fluoride hexafluoropropylene, polyvinyl chloride, polyoxyethylene, polyethylene glycol, polyvinyl acetal, polyacrylonitrile, polyoxypropylene, and polypropylene oxide.

7. The battery of claim 3, wherein the pore former comprises at least one of propylene carbonate, dimethylformamide, nitrogen methyl pyrrolidone, dibutyl phthalate, triglyme, and polyvinylpyrrolidone.

8. The battery according to any one of claims 1 to 7, wherein a surface of the elastic body has tackiness to generate adhesion to the electrode assembly.

9. The battery according to any one of claims 1 to 7, wherein a side surface of the case is provided with a liquid injection port, and a gap between the liquid injection port and a side surface of the electrode assembly is not provided with the elastic body.

10. The battery according to claim 9, wherein the width at the liquid inlet is 3mm to 10 mm.