Battery

Abstract

To provide a battery capable of suppressing the movement of an electrode tab.SOLUTION: A battery 10 comprises: an electrode lamination body 20 in which a plurality of positive electrodes 21 and a plurality of negative electrodes 22 are laminated; a long-sized positive electrode tab 30 and a long-sized negative electrode tab 40 which are connected to the electrode lamination body 20; and an outer covering 50 that covers the electrode lamination body 20. One end 31 side of the positive electrode tab 30 and one end 41 side of the negative electrode tab 40, are housed in the inside of the outer covering 50. The other end 32 side of the positive electrode tab 30 and the other end 42 side of the negative electrode tab 40 project to the outside of the outer covering 50. In the inside of the outer covering 50, the positive electrode tab 30 includes: a region A1 overlapped with the electrode lamination body 20; and regions A2 and A3 which are not overlapped with the electrode lamination body 20. At least one of the positive and negative electrode tabs, e.g., the positive electrode tab 30, is held by being sandwiched by tab holding members 60 arranged onto the outer side of the outer covering 50 in at least one part of the regions A2 and A3 which are not overlapped with the electrode lamination body 20.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a battery.

Background Art

[0002] The electrochemical element of Patent Document 1 includes an electrode assembly in which electrodes and a separator are laminated, and a battery case that houses the electrode assembly. The electrode has an electrode tab that protrudes from the battery case. The portion of the electrode tab exposed from the battery case is fixed by a tab holder.

[0003] The battery pack of Patent Document 2 includes unit cells. Each unit cell has a laminated electrode body, a positive electrode lead tab, and a negative electrode lead tab drawn from a film-like exterior material. A laminate movement restraining member is attached to the lower end welded portion laminate of the unit cell.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the electrochemical element of Patent Document 1, one end of the electrode tab (the end on the side housed in the battery case) is a free end. Therefore, one end of the electrode tab is likely to move. In the battery pack of Patent Document 2, although bending of the exterior material or the like may indirectly contribute to suppressing vibration of the tab, the movement of the tab cannot be sufficiently suppressed.

[0006] An object of the present disclosure is to provide a battery capable of suppressing movement of an electrode tab.

Means for Solving the Problems

[0007] The battery of the present disclosure includes an electrode laminate in which a plurality of electrode plates are stacked, a pair of longitudinal electrode tabs connected to the electrode laminate, and an exterior body that wraps the electrode laminate. One end side of each of the electrode tabs is housed inside the exterior body, and the other end side of each of the electrode tabs protrudes outside the exterior body. Inside the exterior body, each of the electrode tabs has a region overlapping the electrode laminate and a region not overlapping the electrode laminate. At least one of the electrode tabs is held by being sandwiched by a tab holding member disposed outside the exterior body in at least a part of the non-overlapping region.

Advantages of the Invention

[0008] According to the present disclosure, it is possible to provide a battery capable of suppressing the movement of the electrode tabs.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0010] <Embodiment 1> This embodiment applies the present invention to the battery 10 shown in FIG. 1.

[0011] (Configuration of the battery) The battery 10 shown in FIG. 1 of the present embodiment is, for example, a secondary battery. The battery 10 is, for example, a lithium-ion battery. The battery 10 includes an electrode laminate 20 (see FIG. 2), a pair of electrode tabs (a positive electrode tab 30 and a negative electrode tab 40), an exterior body 50, and a plurality (eight in this embodiment) of tab holding members 60.

[0012] In the following description, for convenience of explanation, the vertical direction shown in FIGS. 1-3 is defined as the vertical direction as it is, but it does not have to match the vertical direction in the actual arrangement state of the battery 10.

[0013] The electrode laminate 20 is sealed in the exterior body 50 together with the electrolytic solution. The electrode laminate 20 is configured by laminating a plurality of electrode plates (a positive electrode 21 and a negative electrode 22). The electrode laminate 20 has a plurality of positive electrodes 21, a plurality of negative electrodes 22, and a plurality of separators (not shown). The positive electrode 21, the negative electrode 22, and the separator are laminated such that one separator is interposed between one positive electrode 21 and one negative electrode 22. The separator is made of, for example, a microporous membrane having insulating properties.

[0014] The positive electrode 21 is configured by applying a positive electrode active material to a conductive plate-like member such as an aluminum foil. The positive electrode active material is a material capable of occluding and releasing cations such as lithium ions. One end portion of the positive electrode 21 is a positive electrode side connection portion 21a having a shape that protrudes substantially rectangularly in plan view. The positive electrode active material is not applied to the positive electrode side connection portion 21a. The positive electrode side connection portion 21a is electrically connected to the positive electrode tab 30 in a state where a plurality of them are laminated inside the exterior body 50.

[0015] The negative electrode 22 is configured by applying a negative electrode active material to a conductive plate-like member such as a copper foil. The negative electrode active material is a material capable of occluding and releasing cations such as lithium ions. One end of the negative electrode 22 is a negative electrode side connection portion 22a having a shape protruding substantially rectangularly in plan view. As shown in FIG. 2, in the electrode laminate 20, the negative electrode side connection portion 22a protrudes in a direction opposite to the protruding direction of the positive electrode side connection portion 21a. The negative electrode active material is not applied to the negative electrode side connection portion 22a. The negative electrode side connection portion 22a is electrically connected to the negative electrode tab 40 in a state of being stacked in a plurality of sheets inside the exterior body 50.

[0016] The exterior body 50 is a bag body using a flexible laminate film, for example, a resin film having an aluminum layer. The exterior body 50 wraps the electrode laminate 20. The exterior body 50 is configured by joining (for example, welding) the peripheries of the first exterior portion 51 and the second exterior portion 52.

[0017] The positive electrode tab 30 is a long metal. The positive electrode tab 30 has, for example, a rectangular cross-sectional shape. In the case of FIG. 2, the upper surface 30A and the lower surface 30B of the positive electrode tab 30 are wider than the side surfaces 30C, 30D. A plurality of positive electrode side connection portions 21a are stacked on the upper surface 30A of the positive electrode tab 30.

[0018] One end 31 of the positive electrode tab 30 is accommodated inside the exterior body 50 as shown in FIG. 3. The other end 32 of the positive electrode tab 30 protrudes outside the exterior body 50. The other end 32 of the positive electrode tab 30 is used as an electrical connection portion to the outside.

[0019] As shown in FIGS. 2 and 3, inside the exterior body 50, there are a region A1 overlapping the electrode laminate 20 and regions A2 and A3 not overlapping the electrode laminate 20 on the positive electrode tab 30. The regions A1, A2, and A3 are arranged in order from the one end 31 side to the other end 32 side of the positive electrode tab 30 so as to be aligned with the region A2, the region A1, and the region A3. In the region A1, the lower surfaces of the plurality of stacked positive electrode side connection portions 21a are joined to the upper surface 30A of the positive electrode tab 30. In FIG. 3, as the electrode laminate 20, one with the positive electrode side connection portions 21a stacked appears.

[0020] The negative electrode tab 40 is a longitudinally-shaped metal. The negative electrode tab 40 has, for example, a rectangular cross-sectional shape. In the case of FIG. 2, the upper surface 40A and the lower surface 40B of the negative electrode tab 40 are wider than the side surfaces 40C and 40D. A plurality of negative electrode side connection portions 22a are laminated on the upper surface 40A of the negative electrode tab 40.

[0021] One end 41 of the negative electrode tab 40 is housed inside the exterior body 50. The other end 42 of the negative electrode tab 40 protrudes outside the exterior body 50. The other end 42 of the negative electrode tab 40 is used as an electrical connection portion to the outside.

[0022] As shown in FIG. 2, inside the exterior body 50, there are regions B1 overlapping with the electrode laminate 20 and regions B2 and B3 not overlapping with the electrode laminate 20 on the negative electrode tab 40. The regions B1, B2, and B3 are arranged in order from the one end 41 side to the other end 42 side of the negative electrode tab 40 so as to be aligned with the region B2, the region B1, and the region B3. In the region B1, the lower surfaces of the plurality of laminated negative electrode side connection portions 22a are joined to the upper surface 40A of the negative electrode tab 40.

[0023] As shown in FIGS. 1 and 2, the tab holding member 60 has a three-dimensional shape having two surfaces parallel to the upper and lower surfaces, for example, a rectangular parallelepiped shape. The tab holding members 60 are used in a set of two (a pair). In the present embodiment, four sets and eight tab holding members 60 are used. Here, the arrangement of the tab holding member 60 will be described. Four of the tab holding members 60 are arranged at positions 51A above the regions A2, A3, B2, and B3 in the first exterior portion 51. The position 51A corresponds to a position above the recess 20A of the shoulder, which is the base of the positive electrode side connection portion 21a having a protruding shape in the electrode laminate 20, and a position above the recess 20A of the shoulder, which is the base of the negative electrode side connection portion 22a having a protruding shape in the electrode laminate 20. As shown in FIG. 2, four of the lower tab holding members 60 are arranged on the lower surface of the second exterior portion 52 so as to overlap the upper four tab holding members 60 in the vertical direction. The tab holding member 60 may be fixed to the first exterior portion 51 and the second exterior portion 52 by, for example, an adhesive or the like.

[0024] The tab holding member 60 is preferably made of an elastic member. For example, a rubber sponge is preferable for the tab holding member 60. The type C hardness of the tab holding member 60 is preferably 2 or more and 12 or less as measured in accordance with JIS K7312. The tensile strength of the tab holding member 60 is preferably 0.25 MPa or more and 0.65 MPa or less as measured in accordance with JIS K6767. The elongation of the tab holding member 60 is preferably 200% or more and 220% or less as measured in accordance with JIS K6767. The apparent density of the tab holding member 60 is preferably 0.07 g / cm 3 to 0.13 g / cm 3 or less. The 25% compression load of the tab holding member 60 is preferably 14.7 kPa or more and 44.1 kPa or less.

[0025] As shown in FIG. 3, the pair of tab holding members 60 sandwich the positive electrode tab 30 via the exterior body 50 in the plate thickness direction of the positive electrode tab 30. In this way, the positive electrode tab 30 has a structure in which it is sandwiched and held by the tab holding member 60 disposed outside the exterior body 50 in a region that does not overlap with the electrode laminate 20 (region A2 and a part of region A3 (the portion on the region A2 side)). Similarly, as shown in FIG. 2, the pair of tab holding members 60 sandwich the negative electrode tab 40 via the exterior body 50 in the plate thickness direction of the negative electrode tab 40. In this way, the negative electrode tab 40 has a structure in which it is sandwiched and held by the tab holding member 60 disposed outside the exterior body 50 in a region that does not overlap with the electrode laminate 20 (region B2 and a part of region B3 (the portion on the region B2 side)).

[0026] As shown in FIG. 3, in the battery 10, the lower surface 60A of the upper tab holding member 60 is a flat surface, and the upper surface 30A of the positive tab 30 is also a flat surface. Similarly, the upper surface 60B of the lower tab holding member 60 is a flat surface, and the lower surface 30B of the positive tab 30 is also a flat surface. Therefore, since the force when sandwiching with the pair of upper and lower tab holding members 60 acts on the surface, the sandwiched state of the positive tab 30 is stabilized. The same applies to the sandwiched state of the pair of upper and lower tab holding members 60 with respect to the negative tab 40.

[0027] As shown in FIG. 3, the tab holding member 60 is arranged at a plurality of locations (two locations in the first embodiment) sandwiching the center of gravity G of the positive tab 30 in the positive tab 30. Similarly, the tab holding member 60 is arranged at a plurality of locations (two locations in the first embodiment) sandwiching the center of gravity (not shown) of the negative tab 40 in the negative tab 40. Further, since the tab holding member 60 holds the tabs 30 and 40 near the four corners of the exterior body 50, the tabs 30 and 40 can be held more balanced.

[0028] Note that, as shown in FIG. 3, the tab holding member 60 may be supported by a support member 70 arranged outside the tab holding member 60. As the support member 70, for example, a plate-like member made of metal can be preferably used. The support member 70 may be a part of, for example, a housing (battery case) that houses the battery 10.

[0029] The tab holding member 60 may be fixed to the support member 70 by, for example, an adhesive. As shown in FIG. 3, the upper surface 60C of the upper tab holding member 60 is a flat surface, and the lower surface 70A of the upper support member 70 is also a flat surface. The lower surface 60D of the lower tab holding member 60 is a flat surface, and the upper surface 70B of the lower support member 70 is also a flat surface. Therefore, it is easy to secure the contact area between the tab holding member 60 and the support member 70, and the tab holding member 60 can be stably supported by the support member 70.

[0030] (Function and Effect) In the battery 10 of the present embodiment, the positive electrode tab 30 is held by being sandwiched by a tab holding member 60 disposed outside the exterior body 50 in a region where it does not overlap with the electrode laminate 20 (region A2 and a part of region A3 (the portion on the region A2 side)). Further, the negative electrode tab 40 is held by being sandwiched by a tab holding member 60 disposed outside the exterior body 50 in a region where it does not overlap with the electrode laminate 20 (region B2 and a part of region B3 (the portion on the region B2 side)). With such a configuration, one end 31 side of the positive electrode tab 30 and one end 41 side of the negative electrode tab 40 disposed inside the exterior body 50 can be sandwiched and held by the tab holding member 60. Therefore, the movement (such as vibration and movement) of one end 31 side of the positive electrode tab 30 and one end 41 side of the negative electrode tab 40 can be suppressed. In particular, since the tab holding member 60 sandwiches the tabs 30 and 40 via the exterior body 50 in the plate thickness direction of the tabs 30 and 40, the vibration in the plate thickness direction of the tabs 30 and 40 can be effectively suppressed. Therefore, damage to the battery 10 can be suppressed.

[0031] The tab holding member 60 of the present embodiment is composed of an elastic member. With such a configuration, the tab holding member 60 can function as a member that suppresses the movement (such as vibration and movement) of the tabs 30 and 40.

[0032] The tab holding member 60 of the present embodiment is arranged at a plurality of locations sandwiching the center of gravity of each of the electrode tabs 30 and 40 for each of the tabs 30 and 40. With such a configuration, the tabs 30 and 40 can be held by the tab holding member 60 in a well-balanced manner.

[0033] <Embodiment 2> Hereinafter, Embodiment 2 will be described with reference to FIG. 4. The battery 10 of Embodiment 2 differs from that of Embodiment 1 in the configuration of the tab holding member. Therefore, hereinafter, the same components as those in Embodiment 1 will be denoted by the same reference numerals as in Embodiment 1, and detailed description thereof will be omitted, and the differences from Embodiment 1 will be mainly described.

[0034] As shown in FIG. 4, the tab holding member 260 of Embodiment 2 includes a main body portion 261 and a plurality of protruding portions 262. The main body portion 261 has a three-dimensional shape having two surfaces parallel to the upper and lower surfaces, for example, a rectangular parallelepiped shape, similar to the tab holding member 60 of Embodiment 1. The protruding portion 262 protrudes from the upper surface of the main body portion 261. The protruding portion 262 is elastically deformable. As shown in FIG. 4(A), the tab holding member 260 is disposed at a position 51A in a region (region A2 in FIG. 4(A)) that does not overlap with the electrode laminate 20. When the positive electrode tab 30 vibrates or moves, for example, in the vertical direction, as shown in FIG. 4(A), the protruding portion 262 flexes and deforms. Thereby, the tab holding member 260 can function as a member that suppresses the vibration and movement of the tabs 30 and 40.

[0035] <Other Embodiments> The present invention is not limited to the embodiments described with the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention. (1) In the above-described Embodiment 1, as shown in FIG. 5, a configuration in which a plurality of batteries 10 are stacked with a support member 70 interposed therebetween may be employed. As shown in FIG. 5, the support member 70 may be commonly used between adjacent batteries 10 in the vertical direction. (2) In the above-described Embodiment 1, the battery 10 was a secondary battery, but it may be a primary battery. The battery 10 may be an all-solid-state battery using a solid electrolyte instead of an electrolytic solution. Although the battery 10 was a lithium-ion battery, it may be other types of batteries such as a nickel-metal hydride battery or a nickel-cadmium battery. (3) In the above-described Embodiment 1, a configuration in which the tab holding member 60 is used for the positive electrode tab 30 and the negative electrode tab 40 is shown, but a configuration in which the tab holding member 60 is used for only one of the positive electrode tab 30 and the negative electrode tab 40 may be employed. (4) In the above-described Embodiment 1, a configuration in which two tab holding members 60 are used for each of the tabs 30 and 40 is shown, but a configuration in which one tab holding member 60 is used for each of the tabs 30 and 40 may be employed. For example, a configuration in which the tab holding member 60 is used only for one end 31 of the tab 30 or a configuration in which the tab holding member 60 is used only for one end 41 of the tab 40 may be employed. (5) In the above-described Embodiment 1, a configuration in which two tab holding members 60 are used for each of the tabs 30 and 40 is shown. However, a configuration in which three or more tab holding members 60 are used for each of the tabs 30 and 40 may also be employed. (6) In the above-described Embodiment 1, in the tabs 30 and 40, a region that does not overlap with the electrode laminate 20 may be provided at a position (for example, a position on the center of gravity G) sandwiched by a region that overlaps with the electrode laminate 20. (7) In the above-described Embodiment 1, each of the tabs 30 and 40 protrudes from an edge on one side of the exterior body 50. However, one of the tabs may protrude from an edge on the side opposite to the one side edge. (8) In the above-described Embodiment 1, a part of the plurality of tab holding members 60 may be an integrated member. For example, a pair of tab holding members 60 that overlap in the stacking direction may be integrated. Also, a plurality of tab holding members 60 on the upper side or the lower side of the exterior body 50 may be integrated. (9) In the above-described Embodiment 1, an example in which the tab holding member 60 is fixed to the position 51A of the exterior body 50 by an adhesive or the like is shown. However, a configuration in which they are in contact without being fixed may also be employed. (10) In the above-described Embodiment 1, an example in which the tab holding member 60 is fixed to the support member 70 by an adhesive or the like is shown. However, a configuration in which they are in contact without being fixed may also be employed.

[0036] The above examples are merely for illustrative purposes and are not to be construed as limiting the present invention. Although the present invention has been described with reference to examples of typical embodiments, the language used in the description and illustration of the present invention is to be understood as explanatory and exemplary rather than restrictive. As detailed herein, changes can be made within the scope of the appended claims without departing from the scope or essence of the present invention in its form. Here, specific structures, materials, and embodiments have been referred to in the detailed description of the present invention, but it is not intended to limit the present invention to the disclosure herein. Rather, the present invention is intended to cover all functionally equivalent structures, methods, and uses within the scope of the appended claims.

Description of Reference Numerals

[0037] 10… Battery 20… Electrode laminate 21… Positive electrode (electrode plate) 22… Negative electrode (electrode plate) 30… Positive electrode tab (electrode tab) 31… One end of the positive electrode tab 32… The other end of the positive electrode tab 40… Negative electrode tab (electrode tab) 41… One end of the negative electrode tab 42… The other end of the negative electrode tab 50… Outer package 60, 260… Tab holding member A1… Region overlapping with the electrode laminate A2, A3… Regions not overlapping with the electrode laminate B1… Region overlapping with the electrode laminate B2, B3… Regions not overlapping with the electrode laminate

Claims

1. An electrode laminate in which a plurality of electrode plates are laminated, A pair of longitudinal electrode tabs connected to the electrode laminate, An exterior body that wraps the electrode laminate, and comprising: One end side of each of the electrode tabs is housed inside the exterior body, The other end side of each of the electrode tabs protrudes outside the exterior body, Inside the exterior body, each of the electrode tabs has a region overlapping the electrode laminate and a region not overlapping the electrode laminate, At least one of the electrode tabs is held by being sandwiched by a tab holding member disposed outside the exterior body in at least a part of the non-overlapping region. A battery.

2. The battery according to claim 1, wherein the tab holding member is made of an elastic member.

3. The battery according to claim 2, wherein the tab holding member is disposed at a plurality of locations sandwiching the center of gravity of each of the electrode tabs for each of the electrode tabs.

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