Power storage device and method for manufacturing power storage device

Abstract

This power storage device (10) includes: an outer can (15) having an opening; an electrode body (14) which is accommodated in the outer can (15) together with an electrolyte and in which a positive electrode plate (11) and a negative electrode plate (12) are wound with a separator (13) interposed therebetween; and a sealing body (16) which closes the opening of the outer can (15). A shielding member (20) is provided between the outer can (15) and the sealing body (16). The outer can (15), the shielding member (20), and the sealing body (16) are joined. The shielding member (20) has an eaves part (21) positioned between the sealing body (16) and the electrode body (14) and extending radially toward the inside of the outer can (15).

Description

Electricity storage device and method for manufacturing the same

[0001] The present disclosure relates to an electricity storage device and a method for manufacturing an electricity storage device.

[0002] The power storage device includes an electrode assembly in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween, an electrolyte, a cylindrical outer can with a bottom that contains the electrode assembly and the electrolyte, and a sealing member that closes the opening of the outer can. For example, in the power storage device described in Patent Document 1, the outer can and the sealing member are sealed by laser welding.

[0003] Japanese Utility Model Application Laid-Open Publication No. 02-54162

[0004] In the future, power storage devices will be required to be charged and discharged in even harsher environments or conditions, and the reliability of the power storage devices will need to be further improved.

[0005] Therefore, an object of the present disclosure is to provide a power storage device and a method for manufacturing a power storage device that can improve reliability.

[0006] The energy storage device according to the present disclosure is an energy storage device having an outer can with an opening, an electrode assembly in which a first electrode plate and a second electrode plate are wound with a separator interposed therebetween and housed in the outer can together with an electrolyte, and a sealing body that closes the opening of the outer can, wherein a shielding member is provided between the outer can and the sealing body, the outer can, the shielding member, and the sealing body are joined together, and the shielding member is located between the sealing body and the electrode assembly and has a visor portion that extends radially toward the inside of the outer can.

[0007] The manufacturing method for an energy storage device according to the present disclosure is a manufacturing method for an energy storage device having an electrode assembly in which a first electrode plate and a second electrode plate are wound with a separator interposed therebetween, an electrolyte, a cylindrical outer can with a bottom that contains the electrode assembly and the electrolyte, a sealing body that closes the opening of the outer can, and a shielding member that is provided between the opening of the outer can and the sealing body, and in which at least one of the outer can and the shielding member is joined to the sealing body, and is characterized by having a first step of inserting the electrode assembly into the outer can, a second step of inserting the shielding member into the opening of the outer can, a third step of injecting the electrolyte into the outer can, a fourth step of arranging the sealing body on the shielding member, and a fifth step of joining the outer can, the shielding member, and the sealing body.

[0008] According to the power storage device and the method for manufacturing the power storage device of the present disclosure, reliability can be improved.

[0009] FIG. 1 is a schematic diagram showing an electric storage device according to an embodiment; FIG. 2 is a flow diagram showing a flow of a manufacturing process for an electric storage device according to an embodiment; FIG. 3 is a flow diagram showing a part of a manufacturing process for an electric storage device according to another embodiment; FIG. 4 is a schematic diagram showing a part of a manufacturing process for an electric storage device according to another embodiment; FIG. 5 is a schematic diagram showing a shielding member according to another embodiment; FIG. 6 is a schematic diagram showing a shielding member according to another embodiment; FIG. 7 is a schematic diagram showing a shielding member according to another embodiment; FIG. 8 is a schematic diagram showing a shielding member according to another embodiment; FIG. 9 is a schematic diagram showing a shielding member according to another embodiment; FIG. 10 is a schematic diagram showing a shielding member according to another embodiment;

[0010] An example of an embodiment of the present disclosure will be described in detail below. In the following description, specific shapes, materials, directions, numerical values, etc. are examples for facilitating understanding of the present disclosure, and can be appropriately changed according to the application, purpose, specifications, etc.

[0011] [Electricity Storage Device] An electric power storage device 10 as an example of an embodiment will be described with reference to FIG.

[0012] The energy storage device 10 is, for example, a cylindrical battery, and has an electrode body 14, an electrolyte, an outer can 15 that contains the electrode body 14 and the electrolyte, a sealing body 16 that closes the opening of the outer can 15, and a shielding member 20 that is provided between the outer can 15 and the sealing body 16.

[0013] The electrode assembly 14 includes a positive electrode plate 11, a negative electrode plate 12, and a separator 13, and has a structure in which the positive electrode plate 11 and the negative electrode plate 12 are spirally wound with the separator 13 interposed therebetween. In the following description, for convenience of explanation, the sealing body 26 side of the energy storage device 10 (the opening side of the outer can 15) is referred to as the top, and the bottom side of the outer can 15 is referred to as the bottom.

[0014] The positive electrode plate 11 has a positive electrode core and a positive electrode mixture layer formed on at least one surface of the core. The positive electrode core can be a foil of a metal, such as aluminum or an aluminum alloy, that is stable within the potential range of the positive electrode plate 11, or a film with such a metal disposed on the surface. The positive electrode mixture layer contains a positive electrode active material, a conductive agent such as acetylene black, and a binder such as polyvinylidene fluoride, and is preferably formed on both sides of the positive electrode core. For example, a lithium transition metal composite oxide is used as the positive electrode active material. The positive electrode plate 11 can be manufactured by applying a positive electrode mixture slurry containing a positive electrode active material, a conductive agent, a binder, etc., onto the positive electrode core, drying the coating, and then compressing the coating to form a positive electrode mixture layer on both sides of the core.

[0015] The negative electrode plate 12 has a negative electrode core and a negative electrode mixture layer formed on at least one surface of the core. The negative electrode core can be a foil of a metal, such as copper or a copper alloy, that is stable within the potential range of the negative electrode plate 12, or a film with such a metal disposed on the surface. The negative electrode mixture layer contains a negative electrode active material and a binder such as styrene-butadiene rubber (SBR), and is preferably formed on both sides of the negative electrode core. Examples of the negative electrode active material include graphite and silicon-containing compounds. The negative electrode plate 12 can be manufactured by applying a negative electrode mixture slurry containing a negative electrode active material and a binder to the negative electrode core, drying the coating, and then compressing the coating to form a negative electrode mixture layer on both sides of the core.

[0016] The electrolyte solution includes a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. Examples of the non-aqueous solvent include esters, ethers, nitriles, amides, and mixed solvents of two or more of these. Examples of the non-aqueous solvent include ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and mixed solvents of these. The non-aqueous solvent may contain a halogen-substituted compound (e.g., fluoroethylene carbonate) in which at least a portion of the hydrogen atoms of these solvents are substituted with halogen atoms such as fluorine. Examples of the electrolyte salt include LiPF ６ Lithium salts such as

[0017] The energy storage device 10 may have insulating plates disposed above and below the electrode body 14. The positive electrode lead connected to the positive electrode plate 11 may extend toward the sealing body 16 through a through-hole in the insulating plate, and the negative electrode lead connected to the negative electrode plate 12 may extend toward the bottom side of the outer can 15 through the outside of the insulating plate. The positive electrode lead may be connected to the bottom surface of the sealing plate 18 that constitutes the sealing body 16 by welding or the like. In this way, the sealing body 16 becomes the positive electrode external terminal. The negative electrode lead may be connected to the inner surface of the bottom part of the outer can 15 by welding or the like. In this way, the outer can 15 becomes the negative electrode external terminal.

[0018] The sealing body 16 includes an annular outer ring 17, a disk-shaped sealing plate 18, and a gasket 19 interposed between the outer ring 17 and the sealing plate 18. The outer ring 17 has an annular base and a cylindrical portion extending from the base. The outer ring 17 is formed into a U-shaped cross section with an open radially inward side by bending the tip of the cylindrical portion toward the center in the radial direction. This U-shape allows the sealing plate 18 to be pressed (clamped) against the outer ring 17 in the thickness direction of the sealing plate 18 via the gasket 19. The sealing body 16 may be provided with a current interrupter (CID) or an exhaust valve that ruptures when the pressure inside the outer can 15 reaches or exceeds a predetermined value. The exhaust valve may be configured, for example, by forming an annular thin-walled portion in the sealing plate 18.

[0019] The shielding member 20 prevents the electrolyte from adhering to the inner peripheral surface of the outer can 15 when the electrolyte is injected into the outer can 15 (third steps S14 and S24 described later) during the manufacturing process of the energy storage device 10. The shielding member 20 can improve the reliability of the energy storage device 10. The shielding member 20 has a wall portion 21 provided between the outer can 15 and the outer ring 17 of the sealing body 16, and a visor portion 22 that protrudes radially inward below the sealing body 16.

[0020] The outer can 15 and the wall portion 21 of the shielding member 20 are welded together. The wall portion 21 of the shielding member 20 and the outer ring 17 of the sealing body 16 are also welded together. Note that the outer can 15, the wall portion 21 of the shielding member 20, and the outer ring 17 of the sealing body 16 may all be welded together.

[0021] [Method for Manufacturing the Energy Storage Device] A manufacturing process for the energy storage device 10, which is an example of an embodiment, will be described with reference to FIGS. 2 and 3. FIG.

[0022] The manufacturing process for the energy storage device 10 is a process for manufacturing the energy storage device 10 in which the shielding member 20 is provided between the outer can 15 and the sealing body 16, and at least one of the outer can 15 and the shielding member 20 is welded to the sealing body 16. The manufacturing process for the energy storage device 10, as will be described in detail later, can improve the reliability of the energy storage device 10. As shown in FIG. 2 , the manufacturing process for the energy storage device 10 includes a first step S11, a second step S12, a sixth step S13, a third step S14, a fourth step S15, and a fifth step S16, each of which will be described in detail later.

[0023] In a first step S11, the electrode assembly 14 is inserted into the outer can 15. The electrode assembly 14 is produced in a previous step by spirally winding the positive electrode plate 11 and the negative electrode plate 12 with the separator 13 interposed therebetween.

[0024] In the second step S12, the shielding member 20 is inserted into the opening of the outer can 15. Also, in the second step S12, the shielding member 20 is inserted into the outer can 15 until the upper end of the outer can 15 and the upper end of the wall portion 21 of the shielding member 20 are at the same height. Note that in the second step S12, the shielding member 20 may be inserted into the outer can 15 while being pressed evenly by a pressing jig.

[0025] As shown in Fig. 3 , in the sixth step S13, the outer can 15 and the shielding member 20 are welded together. More specifically, in the sixth step S13, the upper end of the opening of the outer can 15 and the upper end of the wall portion 21 of the shielding member 20 are welded all around the circumference by laser welding. Here, in the sixth step S13, the electrolyte has not yet been poured into the outer can 15, and no electrolyte has been attached to the inner periphery of the outer can 15. Therefore, no holes will be generated in the welded portion during the laser welding. This can improve the reliability of the energy storage device 10.

[0026] 3 , in the third step S14, the electrolyte is injected into the outer can 15. More specifically, in the third step S14, a nozzle 91 is inserted into the outer can 15, and the electrolyte is injected from the nozzle 91. At this time, the lower end of the nozzle 91 is inserted below the shielding member 20 and is positioned below the shielding member 20. This makes it less likely that the electrolyte will adhere to the upper surface of the shielding member 20 (the inner circumferential surface of the wall portion 21 and the upper surface of the eaves portion 22) than if the electrolyte were injected with the lower end positioned above the eaves portion.

[0027] In fourth step S15, sealing body 16 is inserted into shielding member 20. More specifically, in fourth step S15, sealing body 16 is inserted into shielding member 20 until the top end of outer can 15, the top end of wall portion 21 of shielding member 20, and the top surface of outer ring 17 of sealing body 16 are flush with each other. Note that in fourth step S15, sealing body 16 may be inserted into shielding member 20 of outer can 15 while being evenly pressed by a pressing jig.

[0028] As shown in Fig. 3 , in the fifth step S16, the shielding member 20 and the sealing body 16 are welded together. More specifically, in the fifth step S16, the upper end of the wall portion 21 of the shielding member 20 and the upper edge of the outer ring 17 of the sealing body 16 are welded all around the circumference by laser welding. Here, in the fifth step S16, as described above, no electrolyte is attached to the upper surface of the shielding member 20. Therefore, no holes are formed in the welded portion during the laser welding. This can improve the reliability of the energy storage device 10.

[0029] Another Method for Manufacturing the Power Storage Device A method for manufacturing the power storage device 10, which is another example of the embodiment, will be described with reference to FIGS. 4 and 5. FIG.

[0030] The manufacturing process for the energy storage device 10 is a process for manufacturing the energy storage device 10 in which the shielding member 20 is provided between the outer can 15 and the sealing body 16, and the outer can 15, the sealing body 16, and the shielding member 20 are welded together. The manufacturing process for the energy storage device 10, as will be described in detail later, can improve the reliability of the energy storage device 10. As shown in FIG. 4 , the manufacturing process for the energy storage device 10 includes a first step S21, a second step S22, a third step S24, a fourth step S25, and a fifth step S26, each of which will be described in detail later.

[0031] In a first step S21, the electrode assembly 14 is inserted into the outer can 15. The electrode assembly 14 is produced in a previous step by spirally winding the positive electrode plate 11 and the negative electrode plate 12 with the separator 13 interposed therebetween.

[0032] 5 , in the second step S22, the shielding member 20 is inserted into the opening of the outer can 15. More specifically, in the second step S22, the shielding member 20 is inserted into the outer can 15 by a predetermined depth. The predetermined depth corresponds to the welding depth in the fifth step S26, which will be described later. Note that in the second step S22, the shielding member 20 may be inserted into the opening of the outer can 15 while being evenly pressed by a pressing jig. Alternatively, the shielding member 20 may be fixed to the outer can 15 with a conductive adhesive or the like, or the shielding member 20 may be fixed to the outer can 15 by tightly fitting the shielding member 20 to the outer can 15 by simply adjusting the relationship between the outer dimensions of the shielding member 20 and the inner dimensions of the outer can 15 in the radial direction.

[0033] 5 , in a third step S24, the electrolyte is injected into the outer can 15. More specifically, in the third step S24, a nozzle 91 is inserted into the outer can 15, and the electrolyte is injected from the nozzle 91. At this time, the lower end of the nozzle 91 is inserted below the shielding member 20 and is positioned below the shielding member 20. This makes it less likely that the electrolyte will adhere to the upper surface of the shielding member 20 (the inner circumferential surface of the wall portion 21 and the upper surface of the eaves portion 22) compared to a method in which the electrolyte is injected with the lower end of the nozzle 91 positioned above the shielding member 20.

[0034] In fourth step S25, sealing body 16 is inserted into shielding member 20. More specifically, in fourth step S25, sealing body 16 is pressed, thereby also pressing shielding member 20, and the entire shielding member 20 is inserted from a state in which it was inserted only a predetermined depth. Then, shielding member 20 is inserted into outer can 15 until the top end of outer can 15, the top end of shielding member 20, and the top surface of outer ring 17 of sealing body 16 are at the same height, and sealing body 16 is inserted into shielding member 20. Note that in fourth step S25, sealing body 16 may be inserted into shielding member 20 while being pressed evenly by a pressing jig.

[0035] 5 , in a fifth step S26, the outer can 15, the shielding member 20, and the sealing body 16 are welded together. At this time, the upper end of the outer can 15, the upper end of the wall portion 21 of the shielding member 20, and the upper edge of the outer ring 17 of the sealing body 16 are welded all around the circumference by laser welding. Here, in the fifth step S26, as described above, no electrolyte is attached to the upper surface of the shielding member 20. Therefore, holes are prevented from being formed in the welded portion during laser welding. This can improve the reliability of the energy storage device 10.

[0036] 6 to 9, a shielding member as another example of an embodiment will be described. The shielding member described below has the same configuration and effect as the above-described shielding member 20. Below, configurations and effects that differ from those of the above-described shielding member 20 will be described.

[0037] 6, the shielding member 30 has a wall portion 31 provided between the outer can 15 and the outer ring 17 of the sealing body 16, and an eave portion 32 that protrudes radially inward below the sealing body 16. The eave portion 32 is inclined downward as it extends radially inward.

[0038] With the above configuration, even if the electrolyte adheres to the upper surface of the overhanging portion 32 in the third steps S14 and S24, the inclination of the overhanging portion 32 allows the adhered electrolyte to flow downward. Therefore, holes are not generated in the welded portion during laser welding. This improves the reliability of the energy storage device 10.

[0039] Furthermore, the upper surface of the shielding member 30 may be inclined in the radial direction so as to approach the electrode body 14 as it approaches the center of the outer casing can 15, and the eaves portion 32 may become thinner as it approaches the center. This configuration also makes it easier to return the electrolyte adhering to the upper surface of the eaves portion 32 to the electrode body side.

[0040] 7 , the eaves portion 132 of the shielding member 130 may extend at an angle in the radial direction so as to move away from the electrode group toward the center of the outer casing can 15. With this configuration, the electrolyte adhering to the upper surface of the eaves portion 132 can be collected at the base of the eaves portion 132, and adhesion of the electrolyte to the wall portion 131 of the shielding member 130 can be suppressed.

[0041] 8 , the upper surface of the eaves portion 232 of the shielding member 230 is inclined in the radial direction so as to move away from the electrode group toward the center of the outer casing 15, and the thickness of the eaves portion 232 may increase toward the center. Even in this configuration, the electrolyte tends to accumulate at the base of the eaves portion 232, and therefore adhesion of the electrolyte to the wall portion 231 of the shielding member 230 can be suppressed.

[0042] 9 , the upper surface of the canopy portion 332 of the shielding member 330 has a recess, and as an example of this recess, a wavy unevenness may be formed. The electrolyte collects in this unevenness, thereby preventing the electrolyte from adhering to the wall portion 331 of the shielding member 330.

[0043] 10 , the upper surface of the eaves portion 432 of the shielding member 430 has a recess, and as an example of this recess, a ring-shaped groove may be formed. The electrolyte solution collects in this groove, thereby preventing the electrolyte solution from adhering to the wall portion 431 of the shielding member 430.

[0044] 11 , the shielding member 40 has a wall portion 41 provided between the outer can 15 and the outer ring 17 of the sealing body 16, and an eave portion 42 that protrudes radially inward below the sealing body 16. The wall portion 41 of the shielding member 40 is configured so that the frictional force between the inner circumferential surface of the outer can 15 and the outer circumferential surface of the wall portion 41 is greater than the frictional force between the inner circumferential surface of the wall portion 41 and the outer circumferential surface of the outer ring 17 of the sealing body 16. One method for adjusting the frictional force is to change the surface roughness of each circumferential surface.

[0045] With the above configuration, when the same pressing force is applied when inserting the shielding member 20 into the outer can 15 and when inserting the sealing body 16 into the shielding member 20, the insertion depth of the sealing body 16 in the shielding member 20 can be made greater than the insertion depth of the shielding member 20 in the outer can 15.

[0046] As a result, in the fourth step S25 described above, when the sealing body 16 is inserted into the shielding member 20, which has been inserted into the outer can 15 by a predetermined depth using, for example, the pressing jig 92, the sealing body 16 is pressed, thereby also pressing the shielding member 20, and the insertion depth of the sealing body 16 in the shielding member 20 can be made greater than the insertion depth of the shielding member 20 in the outer can 15. Then, by adjusting the difference in the respective frictional forces described above, the shielding member 20 and the sealing body 16 can be inserted so that the top end of the outer can 15, the top end of the wall portion 21 of the shielding member 20, and the top surface of the outer ring 17 of the sealing body 16 are at the same height.

[0047] 12 , the shielding member 50 has a wall portion 51 provided between the outer can 15 and the outer ring 17 of the sealing body 16, and an eave portion 52 that protrudes radially inward below the sealing body 16. Here, the shielding member 50 is configured so that the gap C1 between the outer can 15 and the wall portion 51 is 0 or less, and the gap C2 between the wall portion 51 and the outer ring 17 of the sealing body 16 is greater than 0. As a result, the frictional force between the wall portion 51 of the shielding member 50 and the outer can 15 is greater than the frictional force between the wall portion 51 of the shielding member 50 and the outer ring 17 of the sealing body 16.

[0048] This provides the same effect as the above-described shielding member 40. By adjusting the difference in the respective gaps described above, it is possible to insert the shielding member 20 and the sealing body 16 so that the top end of the outer can 15, the top end of the wall portion 21 of the shielding member 20, and the top surface of the outer ring 17 of the sealing body 16 are at the same height.

[0049] 13 , the shielding member 60 has a wall portion 61 provided between the outer can 15 and the outer ring 17 of the sealing body 16, and an eave portion 62 that protrudes radially inward below the sealing body 16. Here, the wall portion 61 of the shielding member 60 is configured so that the outer circumferential surface of the wall portion 61 that abuts against the outer can 15 slopes radially inward as it extends downward, and the inner circumferential surface of the wall portion 61 that abuts against the sealing body 16 slopes radially inward as it extends downward. In addition, the inclination angle θ1 of the outer circumferential surface of the wall portion 61 with respect to the vertical direction is configured to be smaller than the inclination angle θ2 of the inner circumferential surface of the wall portion 61 with respect to the vertical direction.

[0050] This provides the same effect as the above-described shielding member 40. By adjusting the difference in the respective inclination angles described above, it is possible to insert the shielding member 20 and the sealing body 16 so that the top end of the outer can 15, the top end surface of the wall portion 21 of the shielding member 20, and the top end surface of the outer ring 17 of the sealing body 16 are at the same height.

[0051] [Summary] The present disclosure is further described by the following embodiments. Configuration 1: An energy storage device including an outer can having an opening, an electrode assembly in which a first electrode plate and a second electrode plate are housed in the outer can together with an electrolyte and wound with a separator interposed therebetween, and a sealing body that closes the opening of the outer can, wherein a shielding member is provided between the outer can and the sealing body, the outer can, the shielding member, and the sealing body are joined together, and the shielding member has an eave portion that is located between the sealing body and the electrode assembly and extends radially toward the inside of the outer can. Configuration 2: The energy storage device according to configuration 1, wherein the eave portion extends toward the electrode assembly or extends at an angle away from the electrode assembly. Configuration 3: The energy storage device according to configuration 1, wherein the upper surface of the eaves portion is inclined radially toward the center of the outer can so as to approach the electrode assembly, and the eaves portion becomes thinner toward the center of the outer can. Configuration 4: The energy storage device according to configuration 1, wherein the upper surface of the eaves portion is inclined radially toward the center of the outer can so as to move away from the electrode assembly, and the eaves portion becomes thicker toward the center of the outer can. Configuration 5: The energy storage device according to any one of configurations 1 to 4, wherein a recess is formed in the upper surface of the eaves portion. Configuration 6: The energy storage device according to configuration 1, wherein the shielding member has a cylindrical wall portion provided between the outer can and the sealing body, and the frictional force between the outer can and the wall portion is greater than the frictional force between the wall portion and the sealing body. Configuration 7: The energy storage device according to Configuration 1, wherein the shielding member has a cylindrical wall portion provided between the outer can and the sealing body, and a gap between the outer can and the wall portion is smaller than a gap between the wall portion and the sealing body.a sealing member that is electrically connected to the first electrode plate, a sealing plate that is electrically connected to the first electrode plate, a ring-shaped gasket that surrounds the outer periphery of the sealing member, and a ring-shaped outer ring that is electrically connected to the second electrode plate, the sealing member having a cylindrical wall that is disposed between the outer can and the sealing member, an outer peripheral surface of the wall that contacts the outer can and slopes radially inward as it extends downward, and an inner peripheral surface of the wall that contacts the sealing member and slopes radially inward as it extends downward, the outer peripheral surface of the wall that contacts the sealing member and slopes radially inward as it extends downward, and the angle of inclination of the outer peripheral surface of the wall with respect to the vertical is smaller than the angle of inclination of the inner peripheral surface with respect to the vertical. 10. The electric storage device according to claim 1, wherein a fusion zone is formed that extends across the sealing body, the shielding member, and the outer can, and the sealing body, the shielding member, and the outer can are joined together. Aspect 11: A method for manufacturing an electricity storage device having an electrode assembly formed by winding a first electrode plate and a second electrode plate with a separator interposed therebetween, an electrolyte, a cylindrical outer can with a bottom that houses the electrode assembly and the electrolyte, a sealing body that closes an opening of the outer can, and a shielding member provided between the opening of the outer can and the sealing body, wherein at least one of the outer can and the shielding member is joined to the sealing body, the method comprising: a first step of inserting the electrode assembly into the outer can, a second step of inserting the shielding member into the opening of the outer can, a third step of injecting the electrolyte into the outer can, a fourth step of arranging the sealing body on the shielding member, and a fifth step of joining the outer can, the shielding member, and the sealing body together. Aspect 12: A method for manufacturing an electricity storage device according to Aspect 11, further comprising a sixth step of joining the outer can and the shielding member after the second step.Aspect 13: The method for manufacturing an electric storage device according to Aspect 12, wherein in the second step, the shielding member is inserted by a predetermined depth, and the predetermined depth is the depth of the molten portion formed in the fifth step. Aspect 14: The method for manufacturing an electric storage device according to any one of Aspects 11 to 13, wherein in the third step, a lower end of a nozzle for injecting the electrolyte solution is closer to the electrode body than the shielding member.

[0052] It should be noted that the present disclosure is not limited to the above-described embodiments and their variations, and it goes without saying that various modifications and improvements are possible within the scope of the matters described in the claims of the present application.

[0053] REFERENCE SIGNS LIST 10 Energy storage device, 11 Positive electrode plate (first electrode plate), 12 Negative electrode plate (second electrode plate), 13 Separator, 14 Electrode body, 15 Outer can, 16 Sealing body, 17 Outer ring, 18 Sealing plate, 19 Gasket, 20, 30, 40, 50, 60 Shielding member, 21, 31, 41, 51, 61 Wall portion, 22, 32, 42, 52, 62 Eaves portion, 91 Nozzle, S11, S21 First step, S12, S22 Second step, S13 Sixth step, S14, S24 Third step, S15, S25 Fourth step, S16, S26 Fifth step

Claims

1. An energy storage device comprising: an outer can with an opening; an electrode assembly in which a first electrode plate and a second electrode plate are wound with a separator interposed therebetween and housed in the outer can together with an electrolyte; and a sealing body that closes the opening of the outer can; wherein a shielding member is provided between the outer can and the sealing body; the outer can, the shielding member, and the sealing body are joined together; and the shielding member is located between the sealing body and the electrode assembly and has a visor portion that extends radially inward of the outer can.

2. An electric storage device according to claim 1, wherein the eave portion extends toward the electrode body, or the eave portion extends at an angle away from the electrode body.

3. An energy storage device according to claim 1, wherein the upper surface of the eaves portion is inclined in the radial direction so as to approach the electrode body side as it approaches the center of the outer casing, and the eaves portion becomes thinner as it approaches the center of the outer casing.

4. An energy storage device according to claim 1, wherein the upper surface of the eaves portion is inclined radially toward the center of the outer casing so as to move away from the electrode body, and the eaves portion becomes thicker toward the center of the outer casing.

5. The electricity storage device according to any one of claims 1 to 4, wherein a recess is formed on the upper surface of the eave portion.

6. An energy storage device according to claim 1, wherein the shielding member has a cylindrical wall portion provided between the outer can and the sealing body, and the frictional force between the outer can and the wall portion is greater than the frictional force between the wall portion and the sealing body.

7. An energy storage device according to claim 1, wherein the shielding member has a cylindrical wall portion provided between the outer can and the sealing body, and the gap between the outer can and the wall portion is smaller than the gap between the wall portion and the sealing body.

8. An energy storage device according to claim 1, wherein the shielding member has a cylindrical wall portion provided between the outer can and the sealing body, the outer peripheral surface of the wall portion that abuts against the outer can is inclined radially inward as it extends downward, and the inner peripheral surface of the wall portion that abuts against the sealing body is inclined radially inward as it extends downward, and the angle of inclination of the outer peripheral surface of the wall portion relative to the vertical direction is smaller than the angle of inclination of the inner peripheral surface relative to the vertical direction.

9. An energy storage device according to claim 1, wherein the sealing body has a sealing plate electrically connected to the first electrode plate, an annular gasket surrounding the outer periphery of the sealing body, and an annular outer ring disposed outside the gasket and surrounding the gasket, the outer ring being joined to at least one of the outer can and the shielding member, and the outer can being electrically connected to the second electrode plate.

10. An electric storage device according to claim 1, wherein a fusion zone is formed that extends across the sealing body, the shielding member, and the outer can, joining the sealing body, the shielding member, and the outer can.

11. A method for manufacturing an electricity storage device comprising: an electrode assembly in which a first electrode plate and a second electrode plate are wound with a separator interposed therebetween; an electrolyte; a cylindrical outer can with a bottom that contains the electrode assembly and the electrolyte; a sealing body that closes the opening of the outer can; and a shielding member that is provided between the opening of the outer can and the sealing body, wherein at least one of the outer can and the shielding member is joined to the sealing body, the method comprising: a first step of inserting the electrode assembly into the outer can; a second step of inserting the shielding member into the opening of the outer can; a third step of injecting the electrolyte into the outer can; a fourth step of arranging the sealing body on the shielding member; and a fifth step of joining the outer can, the shielding member, and the sealing body together.

12. A method for manufacturing an electric storage device according to claim 11, further comprising a sixth step of joining the outer can and the shielding member after the second step.

13. A method for manufacturing an electric storage device according to claim 12, wherein in the second step, the shielding member is inserted to a predetermined depth, and the predetermined depth is the depth of the molten part formed in the fifth step.

14. A method for manufacturing an electric storage device according to any one of claims 11 to 13, wherein in the third step, the lower end of a nozzle for injecting the electrolyte solution is closer to the electrode body than the shielding member.

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