JP4967650B2 - Secondary battery manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing a secondary battery.

After injecting the electrolyte into the bag body in which the battery element formed by stacking the positive electrode plate, the separator and the negative electrode plate is accommodated, the battery element is passed through the positive electrode terminal and the negative electrode terminal extending from the inside of the bag body to the outside. Gas is generated by charging, and then the gas is discharged to suppress swelling due to gas generation during actual use and to stabilize battery characteristics (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 2001-210372

  However, the bag body in which the battery element is accommodated is formed by joining the peripheral edges of the sheet-shaped exterior material. Further, in order to charge the battery element, the opening for injecting the electrolyte is joined, the bag is sealed, and then the generated gas is discharged by opening the bag, It is necessary to form an opening for discharging water. And the exterior case is formed by joining the opening and sealing the bag. That is, in order to manufacture a secondary battery, multiple times of sealing (bonding) is required, and the number of work steps is increased, which makes it difficult to improve productivity.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a method for producing a secondary battery having good productivity.

In order to achieve the above object, the invention described in claim 1
A battery element formed by laminating a positive electrode plate, a separator, and a negative electrode plate, an outer case that is formed into a bag shape by joining two sheet-like exterior materials at the outer periphery, and accommodates the battery element therein, and A method of manufacturing a secondary battery having a plate-like positive electrode terminal and a negative electrode terminal connected to the positive electrode plate and the negative electrode plate and extending from the inside of the exterior case to the outside,
A plurality of the battery elements are arranged between the two exterior materials so that the gap portions are sandwiched between each other and the positive electrode terminal and the negative electrode terminal are exposed, and the periphery of the exterior material is joined. A peripheral joining step for forming a bag having a first opening for injecting an electrolyte;
An electrolyte injection step for injecting an electrolyte into the bag body via the first opening;
A first sealing step for joining the first opening and sealing the bag;
A gas generating step for generating gas by charging the battery element via the positive electrode terminal and the negative electrode terminal;
An unsealing step for forming a second opening in the bag,
A degassing step for discharging the gas from the inside of the bag body via the second opening,
A second sealing step for joining the second opening and sealing the bag body;
A partition wall forming step for joining the portions of the bag body located in the gap and forming a partition wall partitioning the bag body, and
A secondary battery manufacturing method comprising: a cutting step for cutting the bag body along the partition wall to form a plurality of the secondary batteries.

In order to achieve the above object, the invention described in claim 2
A battery element formed by laminating a positive electrode plate, a separator, and a negative electrode plate, an outer case that is formed into a bag shape by joining two sheet-like exterior materials at the outer periphery, and accommodates the battery element therein, and A method of manufacturing a secondary battery having a plate-like positive electrode terminal and a negative electrode terminal connected to the positive electrode plate and the negative electrode plate and extending from the inside of the exterior case to the outside,
A plurality of the battery elements are arranged between the two exterior materials so that the gap portions are sandwiched between each other and the positive electrode terminal and the negative electrode terminal are exposed, and the periphery of the exterior material is joined. A peripheral joining step for forming a bag having a first opening for injecting an electrolyte;
A first partition wall forming step for partially joining the bag body portions located in the gap and forming a part of the partition wall partitioning the bag body;
An electrolyte injection step for injecting an electrolyte into the bag body via the first opening;
A first sealing step for joining the first opening and sealing the bag;
A gas generating step for generating gas by charging the battery element via the positive electrode terminal and the negative electrode terminal;
An unsealing step for forming a second opening in the bag,
A degassing step for discharging the gas from the inside of the bag body via the second opening,
A second sealing step for joining the second opening and sealing the bag body;
A second partition wall forming step for completing the partition wall part by joining the remaining portions of the bag body located in the gap part except the joined part; and
A secondary battery manufacturing method comprising: a cutting step for cutting the bag body along the partition wall to form a plurality of the secondary batteries.

  According to the first and second aspects of the invention, a plurality of battery elements are collectively sealed by joining two sheet-shaped exterior materials, and a plurality of secondary batteries are formed simultaneously. The Therefore, it is possible to reduce the number of work steps related to sealing per secondary battery. Therefore, a method for manufacturing a secondary battery having good productivity can be provided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a plan view for explaining the secondary battery according to the first embodiment, and FIG. 2 is a sectional view taken along line II-II in FIG.

  The secondary battery 10 includes a battery element 20, an outer case 50, a positive electrode lead (positive electrode terminal) 40, and a negative electrode lead (positive electrode terminal) 45.

  The battery element 20 includes a positive electrode plate made of a current collector 32 coated with a positive electrode active material layer 34, and a negative electrode plate made of a current collector 32 coated with a negative electrode active material layer 36, and a separator ( It is formed by laminating via an electrolyte layer 38.

The positive electrode active material layer 34 includes a positive electrode active material, a conductive additive, a binder, and the like. The positive electrode active material is, for example, a lithium-transition metal composite oxide such as LiMn ₂ O ₄ . The conductive auxiliary agent is, for example, acetylene black, carbon black, graphite, carbon fiber, or carbon nanotube. The binder is, for example, polyvinylidene fluoride (PVDF), styrene butadiene rubber (SBR), or polyimide.

  The negative electrode active material layer 36 includes a negative electrode active material, a conductive additive, a binder, and the like. The negative electrode active material is, for example, hard carbon (non-graphitizable carbon material), graphite-based carbon material, or lithium-transition metal composite oxide.

  The current collector 32 is, for example, an aluminum foil, a copper foil, a stainless steel foil, a titanium foil, a nickel-aluminum clad material, a copper-aluminum clad material, a stainless steel-aluminum clad material, or a combination of these metals. Formed from material. Of the above materials, a positive electrode current collector 32 is selected at a positive electrode potential, and a negative electrode current collector 32 is selected from a material that is stable at a negative electrode potential. Generally, the positive electrode current collector 32 is made of aluminum. A copper foil is used for the negative electrode current collector 32.

  Separator 38 is formed from polyolefin, such as polyethylene and polypropylene, polyamide, and polyimide, for example. The electrolyte retained by the separator 38 is a liquid system or a fluid gel polymer system.

The liquid electrolyte (electrolytic solution) contains an organic solvent, a supporting salt, a small amount of a surfactant, and the like. Examples of the organic solvent include cyclic carbonates such as propylene carbonate (PC) and ethylene carbonate (EC), chain carbonates such as dimethyl carbonate, and ethers such as tetrahydrofuran. The supporting salt is an inorganic acid anion salt such as lithium salt (LiPF ₆ ) or an organic acid anion salt such as LiCF ₃ SO ₃ .

  The gel polymer electrolyte contains an electrolytic solution, a host polymer, and the like. The host polymer is a polymer having no lithium ion conductivity, such as a copolymer of polyvinylidene fluoride and hexafluoropropylene (PVDF-HFP), PAN (polyacrylonitrile (PAN), PMMA (polymethyl methacrylate (PMMA)), PEO It is a polymer (solid polymer electrolyte) having ion conductivity such as (polyethylene oxide) or PPO (polypropylene oxide).

  The exterior case 50 is formed in a bag shape by joining the peripheral edges of the sheet-shaped exterior material 52 by heat welding, and is used to accommodate the battery element 20. The exterior material 52 is a polymer-metal composite laminate film having a three-layer structure, and includes a metal layer 54 and a polymer resin layer 56 disposed on both surfaces of the metal layer 54.

  The metal layer 54 is made of, for example, a metal foil such as aluminum, stainless steel, nickel, or copper. The polymer resin layer 56 is made of, for example, a heat-welding resin film such as polyethylene, polypropylene, modified polyethylene, modified polypropylene, ionomer, or ethylene vinyl acetate. In addition, joining of the exterior material 52 is not limited to applying heat welding.

  The positive electrode lead 40 and the negative electrode lead 45 are connected to the current collector 32 of the battery element 20 and extend from the inside of the outer case 50 to the outside in order to draw current from the battery element 20.

  FIG. 3 is a process diagram for explaining the manufacturing method of the secondary battery according to the first embodiment.

  The manufacturing method of the secondary battery 10 includes a peripheral joining step, an electrolyte injection step, a first sealing step, a gas generation step, an opening step, a degassing step, a second sealing step, a partition wall forming step, and a cutting step.

  In the peripheral joining step, the plurality of battery elements 20 are arranged between the two exterior members 52 so that the gaps are sandwiched between the two exterior members 52 and the positive electrode lead 40 and the negative electrode lead 45 are exposed. A bag having a first opening for injecting an electrolyte is formed by joining a part of the periphery of 52 and injecting the electrolyte. In the electrolyte injection step, the electrolyte is injected into the bag body through the first opening.

  In a 1st sealing process, a 1st opening part is joined and a bag body is sealed. In the gas generation step, gas is generated by charging the battery element 20 via the positive electrode lead 40 and the negative electrode lead 45. In the opening process, a second opening is formed in the bag. In the degassing step, gas is discharged from the inside of the bag through the second opening. In the second sealing step, the second opening is joined and the bag is sealed. In the partition wall forming step, a partition wall partitioning the bag body is formed to which the portions of the bag body located in the gap are joined. In the cutting step, the bag body is cut along the partition wall, and a plurality of secondary batteries 10 are formed.

  As described above, a plurality of battery elements are collectively sealed, and a plurality of secondary batteries 10 containing the battery elements are formed simultaneously. Therefore, it is possible to reduce the number of work steps related to sealing per secondary battery.

  Next, each step will be described in detail with reference to FIGS. 4 is a plan view for explaining the peripheral edge bonding step shown in FIG. 3, FIG. 5 is a plan view for explaining the electrolyte injection step following FIG. 4, and FIG. 6 follows FIG. FIG. 7 is a plan view for explaining the gas generation step following FIG. 6, and FIG. 8 is a plan view for explaining the unsealing step following FIG. FIG. 9 is a plan view for explaining the degassing process following FIG. 8, FIG. 10 is a plan view for explaining the second sealing process following FIG. 9, and FIG. 10 is a plan view for explaining a partition wall forming process following FIG. 10, and FIG. 12 is a plan view for explaining a cutting process following FIG.

  In the peripheral joining step, first, two battery elements 20 having a substantially rectangular shape are disposed between two substantially rectangular exterior members 52. The battery elements 20 are juxtaposed with the gap 150 interposed therebetween, and the positive electrode lead 40 and the negative electrode lead 45 are positioned so as to be exposed from the exterior material 52.

  Thereafter, the outer periphery of the exterior member 52 is joined leaving one side as shown in FIG. 4, and the bag body 100 having the joints 115, 125, 135 and the first opening 142 is formed.

  The joining part 115 is formed by joining the first side 110 from which the positive electrode lead 40 is drawn. The joining part 125 is formed by joining the second side 120 extending at a right angle to the first side 110. The joining portion 135 is formed by joining the third side 130 that extends at a right angle to the second side 120 and from which the negative electrode lead 45 is drawn. The first opening 142 is located on the fourth side 140 facing the second side 120, and is formed from a non-joined portion on the periphery of the exterior material 52.

  The order of forming the joint portions 115, 125, and 135 is not particularly limited, and can be formed in a lump. The arrangement positions of the first opening 142 and the joint 125 can be switched. It is also possible to arrange the first opening 142 on the first side 110 from which the positive electrode lead 40 is drawn or the third side 130 from which the negative electrode lead 45 is drawn.

  In the electrolyte injection step, the electrolyte is injected into the bag body 100 through the first opening 142. The method of injecting the electrolyte is not particularly limited, and it is also possible to inject directly by inserting a tube or a nozzle into the opening 142 or inject by immersing in the electrolyte.

  In the first sealing step, the bag body 100 is sealed by joining the first opening 142 used for injecting the electrolyte to form the joint 145.

  The gas generation process includes an initial charging process for generating an initial gas from the battery element 20 and an aging process for further generating gas and stabilizing battery characteristics after the initial charging process.

  In the initial charging step, the battery is initially charged until the battery element 20 generates the battery voltage obtained when charging up to a predetermined ratio of the battery capacity of the battery element 20. When the initial charging temperature is lower than 45 ° C., gas generation is insufficient, and when it is higher than 70 ° C., battery characteristics may be deteriorated, so that the temperature is preferably 45 to 70 ° C. When the predetermined ratio of the battery capacity is lower than 30%, the formation of the inert film on the negative electrode surface becomes insufficient, and when it is higher than 50%, the influence on the formation of the inert film is small. 30 to 50%, more preferably 35 to 45%.

  In the aging process, the battery element 20 is held in a state of being charged by the amount of electricity obtained when charging to 95 to 105% of the battery capacity of the battery element 20. The charging temperature is about 25 ° C. When the holding temperature is lower than 60 ° C., gas generation is insufficient. When the holding temperature is higher than 70 ° C., battery characteristics may be deteriorated. A preferable range of the holding time is influenced by the holding temperature, and is 50 to 72 hours in the case of a holding temperature of 60 ° C., and 40 to 55 hours in the case of a holding temperature of 70 ° C.

  As described above, in the gas generation step, gas is generated by charging the battery element 20 positioned inside the sealed bag body 100 via the positive electrode lead 40 and the negative electrode lead 45.

  In the opening process, the bonding portion 145 is peeled off and the bag body 100 is opened, so that the second opening portion 147 is formed on the fourth side 140. Note that the bonding portion 125 facing the bonding portion 145 can be peeled to form the second opening 147. In addition, the second opening 147 can be formed by peeling off the bonding portion 115 or the bonding portion 135.

  In the degassing step, for example, by holding the bag body 100 in a dry atmosphere of about 60 ° C. (dew point is −20 ° C.) and pressing with a load of 0.4 MPa, the second opening 147 is passed through, Gas is discharged from the inside of the bag body 100.

  In the second sealing step, the bag body 100 is sealed by joining the second opening 147 and re-forming the joint 146 on the fourth side 140.

  In the partition wall forming step, the portions of the bag body 100 located in the gap 150 are joined to form a partition wall (joint) 155 that partitions the bag body 100. Since the partition wall portion 155 connects the center of the joint portion 115 and the center of the joint portion 135 by extending vertically, independent sealing structures 101 and 102 are formed.

  The sealing structure 101 is formed by the joint portion 115, the joint portion 125, the joint portion 135, and the partition wall portion 155. One of the battery elements 20 is accommodated, and the positive electrode lead 40 and the negative electrode lead 45 are extended to the outside. Yes. The sealing structure 102 is formed by the joint portion 115, the partition wall portion 155, the joint portion 135, and the joint portion 146. The other of the battery elements 20 is accommodated, and the positive electrode lead 40 and the negative electrode lead 45 are extended to the outside. Yes. That is, the sealing structures 101 and 102 correspond to the connected secondary batteries 10.

  In the cutting step, the bag body 100 is cut along the partition wall portion 155, and the sealing structure body 101 and the sealing structure body 102 are separated. That is, a plurality of secondary batteries 10 are formed.

  Next, as a comparative example, a case where secondary batteries are manufactured one by one will be described.

  13 is a process diagram for explaining a method of manufacturing a secondary battery according to a comparative example, FIG. 14 is a plan view for explaining a peripheral edge joining process shown in FIG. 13, and FIG. 15 is shown in FIG. FIG. 16 is a plan view for explaining the second sealing step shown in FIG. 13.

  Unlike the first embodiment, the manufacturing method of the secondary battery according to the comparative example does not include the partition wall forming process and the cutting process, and the peripheral edge bonding process, the electrolyte injection process, the first sealing process, the gas generation process, and the opening. It has a process, a degassing process, and a 2nd sealing process.

  In the peripheral joining step, the peripheral edges of the exterior material are joined to form the bag body 100 having the joints 115, 125, 135 and the first opening 142. Therefore, three joining operations are performed.

  In a 1st sealing process, the 1st opening part 142 used in order to inject | pour electrolyte is joined, and the bag body 100 is sealed because the junction part 145 forms. Therefore, one joining operation is performed.

  In the second sealing step, the bag 100 is sealed by joining the second opening and re-forming the joint 146 on the fourth side 140. Therefore, one joining operation is performed. Note that the second opening is formed by peeling the joint 145 in order to discharge the gas.

  In the comparative example, the joining operation is three times in the peripheral joining step, once in the first sealing step, and once in the second sealing step. That is, a total of five joining operations are performed until one secondary battery is completed.

  On the other hand, in 1st Embodiment, as above-mentioned, in a partition part formation process, one time of joining operation | work is required, and a total of 6 joining operations are implemented. However, since two secondary batteries are completed in this work, when converted into one unit, the joining work is three times. Therefore, 1st Embodiment can reduce the work man-hour concerning sealing with respect to a comparative example.

  As mentioned above, 1st Embodiment can provide the manufacturing method of the secondary battery which has favorable productivity.

  By integrating the second sealing step and the partition wall forming step, the second opening 147 is joined to seal the bag body 100, and at the same time, the parts of the bag body 100 located in the gap 150 are joined. However, it is also possible to form a partition wall portion 155 that partitions the bag body 100. Moreover, it is also possible to implement a partition part formation process before a 2nd sealing process.

  Next, a second embodiment will be described.

  17 is a process diagram for explaining a manufacturing method of a secondary battery according to the second embodiment, FIG. 18 is a plan view for explaining a first partition wall forming process shown in FIG. 17, and FIG. FIG. 18 is a plan view for explaining a second partition wall forming step shown in FIG. 17. In the following description, members having the same functions as those in the first embodiment are denoted by similar reference numerals, and the description thereof is omitted to avoid duplication.

  In the manufacturing method of the secondary battery according to the second embodiment, the partition wall forming step is divided into two, and the first partition wall forming step positioned between the peripheral edge bonding step and the electrolyte injection step, and the second sealing The second embodiment is generally different from the first embodiment in that it includes a second partition wall forming step positioned between the stopping step and the cutting step. The peripheral joining step, the electrolyte injection step, the first sealing step, the gas generation step, the unsealing step, the degassing step, the second sealing step, and the cutting step are substantially the same as those in the first embodiment, and thus description thereof is omitted. .

  In the first partition wall forming step, the portion of the bag body 200 located in the gap 250 is partially bonded to form the bonded portion 256. The joint portion 256 is a part of a partition wall portion 255 that partitions the bag body 200. Reference numerals 210, 220, 230, and 240 indicate a first side, a second side, a third side, and a fourth side. Reference numerals 215, 225, and 235 indicate joints formed on the first side, the second side, and the third side.

  In the second partition wall forming step, the remainder of the bag body 200 located in the gap 250 excluding the bonded portion is bonded to form a bonded portion 257. The joining portion 256 and the joining portion 257 are integrated to form a partition wall portion 255 that partitions the bag body 200. That is, in the second partition wall forming step, the partition wall 255 is completed. Reference numeral 246 denotes a joint portion formed by joining and re-forming the second opening for gas discharge.

  In the first embodiment, after the electrolyte injection step, the portions of the bag body 200 located in the gap 150 are joined to form the partition wall 155. Therefore, the electrolyte adheres to the battery inner surface of the exterior member 52 of the gap 150, and the bonding strength of the partition wall 155 may be affected by the electrolyte.

  In the second embodiment, part of the partition wall portion 255 (joint portion 256) has already been formed before the electrolyte injection step. Therefore, by suppressing the influence of the electrolyte on the bonding strength of the partition wall portion 255, it is possible to improve the bonding strength of the partition wall portion 255, that is, the outer case 50, as compared with the first embodiment.

  Further, in the second embodiment, since the partition wall forming step is divided into two, compared to the first embodiment, one more joining operation is required, and a total of seven joining operations are performed. . In this operation, two secondary batteries are completed, so when converted into one unit, the bonding operation is 3.5 times. On the other hand, the above comparative example requires a total of five joining operations. Therefore, 2nd Embodiment can reduce the work man-hour concerning sealing with respect to a comparative example.

  As described above, the second embodiment can provide a method for manufacturing a secondary battery that has good productivity and can improve the bonding strength of the outer case.

  Next, a third embodiment will be described.

  20 is a plan view for explaining a peripheral joining step in the method for manufacturing a secondary battery according to the third embodiment, and FIG. 21 is a plan view for explaining injection in an electrolyte injection step following FIG. FIG. 22 is a plan view for explaining the first sealing step following FIG.

  The third embodiment is generally different from the first embodiment in that it has a plurality of first openings for injecting an electrolyte. Since the gas generation step to the cutting step are substantially the same as those in the first embodiment, description thereof is omitted.

  In the peripheral edge bonding step, the peripheral edge of the exterior material is bonded to form the bag body 300 having the bonding portions 315, 325, 335, 345 and the first opening portions 342, 343.

  The joint portion 315 is formed by joining the first side 310 from which the positive electrode lead 40 is drawn. The joint portion 325 is formed by partially joining the second side 320 extending at a right angle to the first side 310, and the unjoined portion constitutes the first opening 342.

  The joint portion 335 is formed by joining a third side 330 that extends at a right angle to the second side 320 and from which the negative electrode lead 45 is drawn. The joint portion 345 extends at a right angle to the third side 330 and is formed by partially joining the fourth side 340 connected to the first side 310, and the unjoined portion is the first opening. 343 is configured.

  The order of forming the joint portions 315, 325, 335, and 345 is not particularly limited, and they can be formed in a lump. The first openings 342 and 343 may be arranged on the first side 310 from which the positive electrode lead 40 is drawn out or the third side 330 from which the negative electrode lead 45 is drawn out.

  In the electrolyte injection step, the electrolyte is injected into the bag 300 through the first openings 342 and 343. At this time, since the electrolyte is injected from two places, it is possible to ensure the liquid injection property. Therefore, by increasing the number of battery elements to be processed in a lump, the bag 300 can be increased in size, and the electrolyte can be injected smoothly, and an increase in the electrolyte injection time can be suppressed. Can do.

  In the first sealing step, the first openings 342 and 343 used for injecting the electrolyte are joined to form the joints 343 and 344, whereby the bag body 300 is sealed.

  As described above, the third embodiment is easy to increase in size as compared with the first embodiment.

  In addition, compared with 1st Embodiment, 3rd Embodiment requires a further one joining operation in a periphery joining process and a 1st sealing process, respectively, and a total of 8 joining operations are implemented. In this operation, two secondary batteries are completed, so when converted into one unit, four bonding operations are performed. On the other hand, the above comparative example requires a total of five joining operations. Therefore, 3rd Embodiment can reduce the work man-hour concerning sealing with respect to a comparative example.

  Next, a fourth embodiment will be described.

  FIG. 23 is a plan view for explaining a first partition wall forming step in the method for manufacturing a secondary battery according to the fourth embodiment.

  The fourth embodiment is generally different from the second embodiment in that it has a plurality of first openings for injecting electrolyte. Since the gas generation step to the cutting step are substantially the same as those in the second embodiment, description thereof is omitted.

  In the peripheral edge bonding step, the peripheral edge of the exterior material is bonded to form the bag body 400 having the bonding portions 415, 425, 435, 445 and the first opening portions 442, 443.

  In the first partition wall forming step, as in the case of the second embodiment, the portion of the bag body 400 located in the gap 450 is partially joined to form the joint 456. The bonding portion 456 is a part of the partition wall portion, and can suppress the influence of the electrolyte on the bonding strength of the partition wall portion and can improve the bonding strength of the partition wall portion, that is, the outer case 50.

  In the electrolyte injection step, the electrolyte is injected into the bag body 400 through the first openings 442 and 443. At this time, since the electrolyte is injected from two places, it is possible to ensure the liquid injection property. Therefore, by increasing the number of battery elements to be processed at once, it is possible to suppress an increase in electrolyte injection time when the bag body 400 is enlarged.

  In the first sealing step, the first openings 442 and 443 used for injecting the electrolyte are joined to form the joined portion, whereby the bag body 400 is sealed.

  As described above, the fourth embodiment can be easily increased in size as compared with the second embodiment.

  In addition, compared with 2nd Embodiment, 4th Embodiment requires a further one joining operation in a periphery joining process and a 1st sealing process, respectively, and a total of 9 joining operations are implemented. In this operation, two secondary batteries are completed, so that when converted into one unit, the bonding operation is 4.5 times. On the other hand, the above comparative example requires a total of five joining operations. Therefore, 4th Embodiment can reduce the work man-hour concerning sealing with respect to a comparative example.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, in the opening process after the gas generation process according to the third embodiment and the fourth embodiment, it is also preferable to form a plurality of second openings for discharging gas. In this case, according to the number of the second openings, the number of times increases because the second openings are joined in the second sealing step.

It is a top view for demonstrating the secondary battery which concerns on this invention. It is sectional drawing which follows the II-II line of FIG. It is process drawing for demonstrating the manufacturing method of the secondary battery which concerns on 1st Embodiment. It is a top view for demonstrating the periphery joining process shown by FIG. FIG. 5 is a plan view for explaining an electrolyte injection process following FIG. 4. It is a top view for demonstrating the 1st sealing process following FIG. It is a top view for demonstrating the gas generation process following FIG. It is a top view for demonstrating the opening process following FIG. It is a top view for demonstrating the degassing process following FIG. It is a top view for demonstrating the 2nd sealing process following FIG. It is a top view for demonstrating the partition part formation process following FIG. FIG. 12 is a plan view for explaining the cutting process following FIG. 11. It is process drawing for demonstrating the manufacturing method of the secondary battery which concerns on a comparative example. It is a top view for demonstrating the periphery joining process shown by FIG. It is a top view for demonstrating the 1st sealing process shown by FIG. It is a top view for demonstrating the 2nd sealing process shown by FIG. It is process drawing for demonstrating the manufacturing method of the secondary battery which concerns on 2nd Embodiment. It is a top view for demonstrating the 1st partition part formation process shown by FIG. It is a top view for demonstrating the 2nd partition part formation process shown by FIG. It is a top view for demonstrating the peripheral joining process in the manufacturing method of the secondary battery which concerns on 3rd Embodiment. It is a top view for demonstrating injection | pouring of an electrolyte injection | pouring process following FIG. It is a top view for demonstrating the 1st sealing process following FIG. It is a top view for demonstrating the 1st partition part formation process in the manufacturing method of the secondary battery which concerns on 4th Embodiment.

Explanation of symbols

10. Secondary battery,
20 .. Battery element,
32 ... current collector,
34 .. Positive electrode active material layer,
36 .. Negative electrode active material layer,
38. ・ Separator,
40. ・ Positive lead (positive terminal),
45 .. Negative electrode lead (negative electrode terminal),
50 ・ ・ Exterior case,
52 .. Exterior material,
54..Metal layer,
56 .. Polymer resin layer,
100 ・ ・ Bag
101, 102 .. Sealing structure,
110 .. first side,
115, 125, 135, 145, 146 .. junction part,
120 .. the second side,
130 .. the third side,
140 .. 4th side,
142 .. first opening,
147 .. second opening,
150 ・ ・ Gap part,
155 .. Bulkhead part,
200 ... bag
210 .. first side,
215,225,235,246,256,257 ...
220 .. second side,
230 .. the third side,
240 .. the fourth side,
250. ・ Gap part,
255 .. Bulkhead part,
300 ... bag
310 .. first side,
315, 325, 335, 343, 344, 345 ..Junction,
320 .. second side,
330 .. the third side,
340 .. the fourth side,
342, 343 .. First opening,
400..Bag body,
415, 425, 435, 445..
442, 443 .. First opening.

Claims (8)

A battery element formed by laminating a positive electrode plate, a separator, and a negative electrode plate, an outer case that is formed into a bag shape by joining two sheet-like exterior materials at the outer periphery, and accommodates the battery element therein, and A method of manufacturing a secondary battery having a plate-like positive electrode terminal and a negative electrode terminal connected to the positive electrode plate and the negative electrode plate and extending from the inside of the exterior case to the outside,
A plurality of the battery elements are arranged between the two exterior materials so that the gap portions are sandwiched between each other and the positive electrode terminal and the negative electrode terminal are exposed, and the periphery of the exterior material is joined. A peripheral joining step for forming a bag having a first opening for injecting an electrolyte;
An electrolyte injection step for injecting an electrolyte into the bag body via the first opening;
A first sealing step for joining the first opening and sealing the bag;
A gas generating step for generating gas by charging the battery element via the positive electrode terminal and the negative electrode terminal;
An unsealing step for forming a second opening in the bag,
A degassing step for discharging the gas from the inside of the bag body via the second opening,
A second sealing step for joining the second opening and sealing the bag body;
A partition wall forming step for joining the portions of the bag body located in the gap and forming a partition wall partitioning the bag body, and
A method for manufacturing a secondary battery, comprising: a cutting step for cutting the bag body along the partition wall to form a plurality of the secondary batteries. A battery element formed by laminating a positive electrode plate, a separator, and a negative electrode plate, an outer case that is formed into a bag shape by joining two sheet-like exterior materials at the outer periphery, and accommodates the battery element therein, and A method of manufacturing a secondary battery having a plate-like positive electrode terminal and a negative electrode terminal connected to the positive electrode plate and the negative electrode plate and extending from the inside of the exterior case to the outside,
A plurality of the battery elements are arranged between the two exterior materials so that the gap portions are sandwiched between each other and the positive electrode terminal and the negative electrode terminal are exposed, and the periphery of the exterior material is joined. A peripheral joining step for forming a bag having a first opening for injecting an electrolyte;
A first partition wall forming step for partially joining the bag body portions located in the gap and forming a part of the partition wall partitioning the bag body;
An electrolyte injection step for injecting an electrolyte into the bag body via the first opening;
A first sealing step for joining the first opening and sealing the bag;
A gas generating step for generating gas by charging the battery element via the positive electrode terminal and the negative electrode terminal;
An unsealing step for forming a second opening in the bag,
A degassing step for discharging the gas from the inside of the bag body via the second opening,
A second sealing step for joining the second opening and sealing the bag body;
A second partition part forming step for completing the partition part by joining the remainder of the part of the bag located in the gap part excluding the joined part; and
A method for manufacturing a secondary battery, comprising: a cutting step for cutting the bag body along the partition wall to form a plurality of the secondary batteries. The exterior material has a substantially rectangular shape,
3. The method for manufacturing a secondary battery according to claim 1, wherein the first opening is formed on two opposing sides of the exterior material that are substantially parallel to the gap. 4.   4. The method of manufacturing a secondary battery according to claim 1, wherein the first opening is formed from a non-joining portion at a peripheral edge of the exterior material. 5.   The said 2nd opening part is formed by peeling the junction part located in the periphery of the said bag body, and opening the said bag body, The any one of Claims 1-4 characterized by the above-mentioned. Of manufacturing a secondary battery.   The gas generation step includes an initial charging step for generating an initial gas from the battery element, and an aging step for further generating gas and stabilizing battery characteristics after the initial charging step. The manufacturing method of the secondary battery of any one of Claims 1-5 characterized by these.   In the initial charging step, the battery element is initially charged until generating a battery voltage obtained when charged to 30 to 50% of the battery capacity of the power generation element in an environment of 45 to 70 ° C. A method for manufacturing a secondary battery according to claim 6.   In the aging step, the battery element is held for 40 to 72 hours in an environment of 60 to 70 ° C. with the amount of electricity obtained when charging to 95 to 105% of the battery capacity of the battery element. The manufacturing method of the secondary battery of Claim 6 or Claim 7 characterized by these.

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