JP2013222656A - Battery laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an increase in the thickness of a battery laminate even when the thickness of individual battery cells is increased, by a simple method.SOLUTION: A plurality of thin plate-like battery cells (10) and a plurality of plate materials (20) are alternately stacked. Each of the battery cells is directly or indirectly fixed to an adjacent plate material. The plate materials are provided with thickness increase absorbing means (27, 31) capable of absorbing an increase in the thickness of the battery cells.

Description

  The present invention relates to a battery stack in which a plurality of thin plate batteries are stacked.

  Non-aqueous electrolyte batteries typified by lithium-ion secondary batteries are characterized by high energy density, so they include various mobile devices such as automobiles and motorcycles, personal digital assistants, uninterruptible power supplies (UPSs), etc. It is used as a power source. In such applications, in order to further improve the energy density, a thin plate-like laminated lithium ion secondary battery in which a power generation element is packaged with a flexible laminate sheet is often used. Furthermore, in order to obtain a desired battery capacity, a battery laminate in which a plurality of thin plate-like secondary batteries (battery cells) are stacked via an insulating sheet and these are connected in series is also practically used (for example, Patent Document 1). reference). The battery stack is used by being housed in a container having a housing space surrounded by a substantially rectangular parallelepiped inner wall.

Patent No. 4499977

  In general, it is known that a secondary battery may expand in volume by repeated charge and discharge. Since the outer sheet of the laminated secondary battery is easily deformed, the secondary battery swells and its thickness increases. In the above battery stack in which a plurality of battery cells are stacked, when the thickness of each battery cell increases, the amount of increase in the thickness of the entire battery stack (dimension along the stacking direction) cannot be ignored. Therefore, there is a possibility that the container that stores the battery stack is deformed by an increase in the thickness of the battery stack, and the container cannot be incorporated into the apparatus or the container is damaged.

  An object of the present invention is to solve the above-described conventional problems and to suppress an increase in the thickness of a battery stack even if the thickness of each battery cell is increased by a simple method.

  The battery laminated body of the present invention is a battery laminated body in which a plurality of thin battery cells and a plurality of plate materials are stacked by alternately arranging battery cells and plate materials. Each of the plurality of battery cells is directly or indirectly fixed to an adjacent plate material. The plate member is provided with a thickness increase absorbing means capable of absorbing an increase in the thickness of the battery cell.

  According to this invention, the thickness increase absorption means which absorbs the increase in thickness by a battery cell swelling is provided in the board | plate material. Therefore, even if the thickness of the battery cell is increased by a simple method, an increase in the thickness of the battery stack can be suppressed.

1A is a perspective view seen from the front side of a battery cell constituting the battery stack according to Embodiment 1 of the present invention, and FIG. 1B is a perspective view seen from the back side thereof. FIG. 2 is a perspective view showing the battery stack according to Embodiment 1 of the present invention. FIG. 3 is an exploded perspective view for explaining the stacking configuration of the battery stack according to the first embodiment of the present invention. FIG. 4A is a front view of a plate material constituting the battery stack according to Embodiment 1 of the present invention, and FIG. 4B is a cross-sectional view of the plate material along the plane including line 4B-4B of FIG. 4A. . FIG. 5 is a front view showing a battery stack according to an embodiment of the present invention. 6A is a front view of a plate material constituting the battery stack according to Embodiment 2 of the present invention, and FIG. 6B is a cross-sectional view of the plate material along the plane including line 6B-6B in FIG. 6A. . 7A is a front view of another plate member constituting the battery stack according to Embodiment 2 of the present invention, and FIG. 7B is a cross-sectional view of the plate member taken along the line including line 7B-7B in FIG. 7A. It is. FIG. 8A is a front view of a plate material constituting the battery stack according to Embodiment 3 of the present invention, and FIG. 8B is a cross-sectional view of the plate material along the plane including line 8B-8B in FIG. 8A. . 9A is a front view of a plate material constituting a battery stack according to Embodiment 4 of the present invention, and FIG. 9B is a cross-sectional view of the plate material along a plane including line 9B-9B in FIG. 9A. . FIG. 10A is a front view of another plate member constituting the battery stack according to Embodiment 4 of the present invention, and FIG. 10B is a cross-sectional view of the plate member taken along the line including line 10B-10B in FIG. 10A. It is. FIG. 11 is a perspective view of another battery cell constituting the battery stack of the present invention as viewed from the front side. FIG. 12A is a front view of another battery stack of the present invention. FIG. 12B is a front view of still another battery stack of the present invention. FIG. 13A is an exploded perspective view illustrating a stacked configuration of still another battery stack of the present invention. FIG. 13B is a front view of the battery stack shown in FIG. 13A.

  In the battery laminate of the present invention, the thickness increase absorbing means may include a through hole or a thin wall portion formed in a region of the plate material facing the battery cell. Alternatively, the thickness increase absorbing means may include a compression deformable buffer member provided between the plate member and the battery cell.

  It is preferable that a notch is formed in the region of the plate material facing the positive electrode tab and / or the negative electrode tab so that the positive electrode tab and the negative electrode tab can be electrically connected between adjacent battery cells. Thus, a plurality of battery cells can be easily formed without protruding the positive electrode tab and the negative electrode tab derived from the battery cell from a rectangle having a minimum area containing a plate material (a rectangle indicated by a two-dot chain line 25 described later). Can be connected in series.

  Below, this invention is demonstrated in detail, showing suitable embodiment. However, it goes without saying that the present invention is not limited to the following embodiments. For convenience of explanation, the drawings referred to in the following description show only the main members necessary for explaining the present invention in a simplified manner among the constituent members of the embodiment of the present invention. Therefore, the present invention can include arbitrary components not shown in the following drawings. In addition, the dimensions of the members in the following drawings do not faithfully represent the actual dimensions of the constituent members and the dimensional ratios of the members.

[Embodiment 1]
(Battery cell)
Initially, the schematic structure of the battery cell used for the battery laminated body concerning Embodiment 1 of this invention is demonstrated.

  1A is a perspective view seen from the front side of the battery cell 10 constituting the battery stack according to Embodiment 1 of the present invention, and FIG. 1B is a perspective view seen from the back side thereof. The battery cell 10 has a substantially rectangular shape in plan view, and has a thin plate shape that is thinner than the vertical and horizontal dimensions of the substantially rectangular shape. In the battery cell 10, a thin plate-shaped power generation element (not shown) having a substantially rectangular plan view shape is enclosed in an exterior made of a laminate sheet 13 together with an electrolytic solution. The power generation element includes a positive electrode in which a positive electrode mixture layer including a positive electrode active material is applied and formed on both surfaces of a predetermined region of the positive electrode current collector, and a negative electrode mixture layer including a negative electrode active material on both surfaces of the predetermined region of the negative electrode current collector Is an electrode laminate in which negative electrodes formed by coating are alternately laminated via separators. The type of the battery is not particularly limited, but a secondary battery, particularly a lithium ion secondary battery is preferable.

  The laminate sheet 13 is thinner than the power generation element and has flexibility. The laminate sheet 13 may be a flexible multilayer sheet in which a heat-fusible resin layer (for example, a modified polyolefin layer) is laminated on the surface of the base layer made of aluminum or the like on the side facing the power generation element. Good. One rectangular laminate sheet 13 is folded in two at the lower side (one short side) 14b so as to sandwich the power generation element, is overlapped along three sides other than the lower side 14b, and is sealed by a heat sealing method or the like. Yes.

  A positive electrode tab 11p and a negative electrode tab 11n are led out from an upper side (the other short side) 14a facing the lower side 14b. The positive electrode tab 11p and the negative electrode tab 11n have a strip shape and extend along a direction orthogonal to the upper side 14a (that is, a direction parallel to a pair of side sides (long sides) 14s adjacent to the upper side 14a). Yes. The positive electrode tab 11p is made of, for example, an aluminum thin plate, and is electrically connected to a plurality of positive electrode current collectors (not shown) constituting the power generation element. The negative electrode tab 11n is made of, for example, a copper thin plate, a nickel-plated copper thin plate, or a copper / nickel clad material, and is electrically connected to a plurality of negative electrode current collectors (not shown) constituting the power generation element. It is connected to the.

  As shown in FIG. 1A, on the front side of the battery cell 10, a rectangular region 16 corresponding to the power generation element is a sealing region of the laminate sheet 13 along the three sides 14 a, 14 s, and 14 s of the battery cell 10. Protrusively. On the other hand, as shown in FIG. 1B, the back surface of the battery cell 10 is substantially flat. In the present invention, for convenience of explanation, the surface on the side where the rectangular projecting region 16 is formed by the power generation element shown in FIG. 1A is called the “front” of the battery cell 10 and is shown in FIG. 1B. The surface on the side that is substantially flat is called the “back surface” of the battery cell 10. A direction connecting the front surface and the back surface is referred to as a “thickness direction”.

(Battery stack)
FIG. 2 is a perspective view showing the battery stack 1 according to Embodiment 1 of the present invention, and FIG. 3 is an exploded perspective view for explaining the stack configuration of the battery stack 1. As shown in FIGS. 2 and 3, a plurality (seven in this example) of battery cells 10 and a plurality (six in this example) of plate members 20 are alternately formed by the battery cells 10 and the plates 20. Arranged and stacked. The plurality of battery cells 10 constituting the battery stack 1 have the same shape, and the plurality of plate members 20 constituting the battery stack 1 have the same shape. In the present invention, the alternate stacking direction of the battery cell 10 and the plate member 20 is referred to as a “stacking direction”.

  FIG. 4A is a front view of the plate member 20. 4B is a cross-sectional view of the plate member 20 taken along the plane including the line 4B-4B in FIG. 4A. The plate material 20 has a substantially rectangular shape as a whole. As shown in FIG. 4A, a notch 21 is formed in a portion excluding both ends of the upper short side of the plate member 20, and as a result, a substantially U-shaped edge is formed on the upper side of the plate member 20. . A substantially rectangular through hole 27 is formed below the notch 21. A substantially rectangular frame-shaped buffer member 31 is fixed to both surfaces of the plate member 20 along the edge of the through hole 27. The buffer member 31 also has an opening corresponding to the through hole 27 of the plate member 20. In FIG. 4A, the outer dimensions of the buffer member 31 in the vertical direction and the horizontal direction substantially match the dimensions of the region 16 (see FIG. 1A) corresponding to the power generation element of the battery cell 10.

  The plate 20 is made of a hard material that can be considered as a rigid body. For example, it is preferably made of an insulating resin material such as polycarbonate or a metal material having excellent thermal conductivity such as copper or aluminum. The thickness of the plate member 20 varies depending on the material of the plate member 20 and the like, but is preferably 0.3 mm or more, more preferably 0.5 mm or more, and particularly preferably 0.8 mm or more. The upper limit of the thickness of the plate member 20 can be appropriately set in consideration of the overall thickness of the battery stack 1 and the like, but is preferably 1.5 mm or less, and more preferably 1.2 mm or less.

  The buffer member 31 has a characteristic that it easily compresses and deforms when a pressing force is applied, and immediately returns to the initial state when the pressing force is released. The material of the buffer member 31 is not particularly limited as long as it has such characteristics. For example, a flexible porous material, so-called sponge, can be used. Specifically, urethane foam, polyethylene foam, rubber sponge and the like can be used. The insulating property of the buffer member 31 is advantageous in preventing a short circuit between adjacent battery cells 10. Although the thickness of the buffer member 31 can be set in consideration of the degree of expansion of the battery cell 10 thickness, it is preferably 0.3 mm or more, and more preferably 0.5 mm or more. If the buffer member 31 is too thick, not only the capacity to absorb the increase in thickness of the battery cell 10 (thickness increase absorption capacity) is improved, but also the overall thickness of the battery stack 1 increases. Accordingly, the upper limit of the buffer member 31 is preferably 1.5 mm or less, and more preferably 1.0 mm or less.

  There is no restriction | limiting in particular in the method of fixing the buffer member 31 to the board | plate material 20, For example, a double-sided adhesive tape and an adhesive agent can be used. In particular, the method of fixing with a double-sided pressure-sensitive adhesive tape is preferable because the stacking process of the battery stack 1 can be performed easily and quickly.

  As shown in FIG. 2 and FIG. 3, the tabs of different polarities (that is, the positive electrode tab 11 p and the negative electrode tab 11 n) are opposed to each other in the stacking direction between two adjacent battery cells 10 with the plate member 20 interposed therebetween. Moreover, every other battery cell 10 is turned over. The positive electrode tab 11p and the negative electrode tab 11n facing each other are electrically connected to each other between the adjacent battery cells 10 with the plate material 20 interposed therebetween via a notch 21 formed in the plate material 20. As a result, the plurality of battery cells 10 are connected in series.

  Each battery cell 10 is indirectly fixed to the adjacent plate member 20 via a buffer member 31. The battery cell 10 is positioned and fixed with respect to the buffer member 31 so that the buffer member 31 is substantially along the outer edge of the power generation element in the battery cell 10. Thus, the plurality of battery cells 10, the plurality of plate members 20, and the buffer member 31 between the battery cell 10 and the plate member 20 are integrated.

  The method for fixing the battery cell 10 and the buffer member 31 is not particularly limited, but the battery cell 10 is buffered by interposing a double-sided adhesive tape or an adhesive between the front or back surface of the battery cell 10 and the buffer member 31. 31 can be fixed. In particular, the method of fixing with a double-sided pressure-sensitive adhesive tape is preferable because the stacking process of the battery stack 1 can be performed easily and quickly.

  FIG. 5 is a plan view of the battery stack 1 as viewed in the stacking direction. All the plate members 20 constituting the battery stack 1 are aligned so that the projected figures along the stacking direction substantially coincide with each other.

  In FIG. 5, an alternate long and two short dashes line 25 indicates a rectangle with the smallest area that encloses the plate material 20. Hereinafter, this rectangle indicated by a two-dot chain line 25 is referred to as a “contour rectangle” of the plate member 20. In the present embodiment, the outline rectangle 25 coincides with the outline of the plate member 20 except for the portion where the notch 21 is formed. As shown in FIG. 5, the battery cell 10 is enclosed in a contour rectangle 25 including the positive electrode tab 11 p and the negative electrode tab 11 n. That is, none of the battery cells 10 protrudes from the outline rectangle 25 of the plate material 20.

  The battery stack 1 according to the present embodiment is generally housed and used in a container having a space (housing space) surrounded by an inner wall having a substantially rectangular parallelepiped shape.

  The effects of the battery stack 1 of the present invention configured as described above will be described.

  The increase in the thickness of the battery cell 10 caused by repeated charging / discharging often occurs when the areas corresponding to the power generation elements on the front surface and the back surface of the battery cell 10 swell in a dome shape.

  As described above, in the battery stack 1 of the first embodiment, the through hole 27 is formed in the region of the plate member 20 facing the battery cell 10, and compression deformation is performed along the edge of the opening of the through hole 27. A possible buffer member 31 is fixed to the plate member 20. The battery cell 10 is indirectly fixed to the plate member 20 via the buffer member 31. Accordingly, when the front and back surfaces of the battery cell 10 swell in a dome shape, the bulge of the battery cell 10 enters the central opening of the frame-shaped buffer member 31 and the through hole 27 of the plate member 20, and the buffer member 31 Compress and deform appropriately. Thus, since the through hole 27 and the buffer member 31 of the plate member 20 function as a thickness increase absorbing unit that absorbs the increase in the thickness of the battery cell 10, even if the thickness of the battery cell 10 increases, the battery stack 1 There is almost no increase in the thickness (dimension in the stacking direction).

  Moreover, according to the first embodiment, the thickness of the battery stack is formed by an extremely simple method of forming the through hole 27 in the plate member 20 and fixing the battery cell 10 to the buffer member 31 provided along the edge. Can be suppressed.

  In the first embodiment, as shown in FIG. 5, when viewed along the stacking direction, the outline rectangle 25 of the plate member 20 includes the battery cell 10 fixed to the plate member 20. Therefore, even if the battery stack 1 is moved in a direction perpendicular to the stacking direction by dropping or vibrating the container containing the battery stack 1, the battery cell 10 is placed on the inner wall of the container. The plate member 20 prevents direct collision. Thus, since possibility that an external force will be directly applied to the battery cell 10 reduces, the deformation | transformation of the battery cell 10 and the possibility that the battery cell 10 will ignite or burst due to it can be reduced. . This is advantageous for improving the safety of the battery stack 1.

  In order to more reliably reduce the possibility of the battery cell 10 colliding with the inner wall of the container, as shown in FIG. 5, the amount of protrusion from the battery cell 10 on each side of the outline rectangle 25 of the plate member 20 (in other words, In this case, it is preferable that the retreat amount D of the battery cell 10 from each side of the outline rectangle 25 is large. The amount of protrusion D can be appropriately set according to the strength of the plate member 20 and the like, but in general, it is preferably 1 mm or more, more preferably 1.5 mm or more, and particularly preferably 2 mm or more. However, if the protruding amount D is too large, not only the safety of the battery stack 1 can be further improved, but also the outer dimension of the battery stack 1 becomes large. In general, the protruding amount D is preferably 4 mm or less, and more preferably 3 mm or less. The protruding amount D of each side of the outline rectangle 25 may be the same on all sides or may be different.

  In the above example, two battery cells 10 that are adjacent to each other with the plate member 20 interposed therebetween are directly opposed to each other through the through hole 27 of the plate member 20. Therefore, when the bulge amount of the battery cell 10 is large, adjacent battery cells 10 may come into contact with each other in the through hole 27 and a harmful short circuit may occur. In order to prevent this, for example, the through hole 27 may be closed with a thin sheet having insulating properties. This sheet can be fixed to one surface of the plate member 20 so as to close the through hole 27. Thereafter, the buffer member 31 may be fixed to the plate member 20. The material of this sheet is not particularly limited as long as it has insulating properties, but any material such as resin or paper can be selected.

(Embodiment 2)
FIG. 6A is a front view of the plate member 20 constituting the battery stack of the second embodiment. 6B is a cross-sectional view of the plate member 20 taken along the plane including the line 6B-6B in FIG. 6A. The second embodiment is different from the first embodiment in that the through hole 27 is not formed in the plate material 20. Similar to the first embodiment, substantially rectangular frame-shaped buffer members 31 are fixed to both surfaces of the plate member 20.

  The battery stack of the second embodiment is the same as the battery stack 1 of the first embodiment except for the above.

  In the second embodiment, when the front and back surfaces of the battery cell 10 swell in a dome shape, the bulge of the battery cell 10 enters the central opening of the frame-shaped buffer member 31, and the buffer member 31 is appropriately compressed and deformed. To do. Thus, since the buffer member 31 functions as a thickness increase absorption unit that absorbs the increase in the thickness of the battery cell 10, even if the thickness of the battery cell 10 increases, the thickness of the battery stack 1 (dimension in the stacking direction). There is almost no increase.

  In the second embodiment, unlike the first embodiment, the through hole 27 is not formed in the plate material 20. Therefore, when the battery cell 10 swells, the battery cell 10 and the plate member 20 may collide, and the thickness increase absorption capability may be limited. However, in such a case, it is possible to ensure the desired thickness increase absorbability by increasing the thickness of the buffer member 31.

  Alternatively, as shown in FIGS. 7A and 7B, the region surrounded by the frame-shaped buffer member 31 on both surfaces of the plate member 20 may be recessed to form a thin portion 28 that is thinner than the others. Good. Thereby, it is possible to ensure a desired thickness increase absorbability while avoiding an increase in the thickness of the buffer member 31.

  In the second embodiment, since the through hole 27 is not formed in the plate material 20, it is possible to avoid a decrease in mechanical strength and a decrease in insulation characteristics of the plate material 20 due to the formation of the through hole 27.

  The second embodiment is the same as the first embodiment except for the above.

(Embodiment 3)
FIG. 8A is a front view of the plate member 20 constituting the battery stack of the third embodiment. FIG. 8B is a cross-sectional view of the plate member 20 along the plane including the line 8B-8B in FIG. 8A. The third embodiment is different from the first embodiment in that a through hole 27 is not formed in the plate member 20 and a substantially rectangular buffer member 32 having an open center is used. The buffer member 32 is fixed to both surfaces of the plate member 20 as in the first embodiment.

  The battery stack of Embodiment 3 is the same as the battery stack 1 of Embodiment 1 except for the above.

  In the third embodiment, when the front and back surfaces of the battery cell 10 swell in a dome shape, the buffer member 31 is appropriately compressed and deformed according to the bulge of the battery cell 10. Thus, since the buffer member 31 functions as a thickness increase absorption unit that absorbs the increase in the thickness of the battery cell 10, even if the thickness of the battery cell 10 increases, the thickness of the battery stack 1 (dimension in the stacking direction). There is almost no increase.

  In the third embodiment, unlike the first embodiment, the through hole 27 is not formed in the plate material 20. Therefore, the increased thickness absorption capacity may be limited. However, in such a case, it is possible to ensure a desired thickness increase absorbability by increasing the thickness of the buffer member 32.

  In the third embodiment, since the through hole 27 is not formed in the plate material 20, it is possible to avoid a decrease in mechanical strength and a decrease in insulation characteristics of the plate material 20 due to the formation of the through hole 27.

  Moreover, since the center of the buffer member 32 is not open, the fixing strength of the buffer member 32 with respect to the plate member 20 and the battery cell 10 can be improved.

  The third embodiment is the same as the first embodiment except for the above.

(Embodiment 4)
FIG. 9A is a front view of the plate member 20 constituting the battery stack of the fourth embodiment. FIG. 9B is a cross-sectional view of the plate member 20 along the plane including the line 9B-9B in FIG. 9A. The fourth embodiment is different from the first embodiment in that no buffer member is used. As in the first embodiment, a substantially rectangular through hole 27 is formed in the plate member 20. The battery cell 10 is directly fixed to the plate member 20 at the edge of the through hole 27. There is no restriction | limiting in particular in the method of fixing the battery cell 10 to the board | plate material 20, For example, a double-sided adhesive tape and an adhesive agent can be used. In particular, the method of fixing with a double-sided pressure-sensitive adhesive tape is preferable because the stacking process of the battery stack 1 can be performed easily and quickly.

  The battery stack of Embodiment 4 is the same as the battery stack 1 of Embodiment 1 except for the above.

  In the fourth embodiment, when the front and back surfaces of the battery cell 10 swell in a dome shape, the bulge of the battery cell 10 enters the through hole 28 of the plate member 20. Thus, since the through hole 28 of the plate material 20 functions as a thickness increase absorbing means that absorbs the increase in the thickness of the battery cell 10, even if the thickness of the battery cell 10 increases, the thickness (stacking direction) of the battery stack 1 is increased. There is almost no increase in dimensions.

  Instead of forming the through hole 27 in the plate member 20, as shown in FIGS. 10A and 10B, a predetermined region in the region where the battery cells 10 on both sides of the plate member 20 face each other is recessed, and FIGS. 7A and 7B A similar thin portion 28 may be formed. The battery cell 10 is directly fixed to the plate member 20 around the thin portion 28. In this case, when the front surface and the back surface of the battery cell 10 swell in a dome shape, the bulge of the battery cell 10 enters a recess formed by the thin portion 28 of the plate member 20. Thus, since the thin portion 28 of the plate member 20 functions as a thickness increase absorbing means that absorbs the increase in the thickness of the battery cell 10, even if the thickness of the battery cell 10 increases, the thickness of the battery stack 1 (stacking direction) There is almost no increase in dimensions. Furthermore, since the through hole 27 is not formed in the plate material 20 of FIGS. 10A and 10B, it is possible to avoid a decrease in mechanical strength and a decrease in insulation characteristics due to the formation of the through hole 27. .

  Furthermore, in this Embodiment 4, since the battery cell 10 is fixed to the board | plate material 20 without passing through a buffer member, the fixed strength with respect to the board | plate material 20 of the battery cell 10 improves. Since no buffer member is used, the number of parts constituting the battery stack is reduced, and the manufacturing process of the battery stack can be simplified.

  The fourth embodiment is the same as the first embodiment except for the above.

  The above-described first to fourth embodiments are merely examples. The present invention is not limited to Embodiments 1 to 4 above, and can be modified as appropriate.

  The battery cell 10 of the present invention is not limited to the configuration shown in FIGS. 1A and 1B, and may be any thin battery cell. For example, the battery cell 10 is a three-side sealed type battery cell in which one laminate sheet 13 is folded in two at the lower side 14b and the laminate sheet 13 is sealed along three sides except the lower side 14b. However, as shown in FIG. 11, a battery cell 10 of a four-sided seal type in which a power generation element is sandwiched between two rectangular laminate sheets 13 of the same size and sealed along four sides including the lower side 14b may be used.

  In the battery cell 10 described above, the positive electrode tab 11p and the negative electrode tab 11n are derived from the common short side 14a. However, the positive electrode tab 11p and the negative electrode tab 11n are derived from either one of the pair of side sides (long sides) 14s. May be. Alternatively, the positive electrode tab 11p and the negative electrode tab 11n may be derived from different sides. Regardless of the lead-out position of the positive electrode tab 11p and the negative electrode tab 11n, the size of the plate material 20 is set so that the outline rectangle 25 of the plate material 20 includes the battery cell 10 including the positive electrode tab 11p and the negative electrode tab 11n. Is preferred. Moreover, it is preferable that a notch is formed in the region of the plate member 20 where the positive electrode tab 11p and the negative electrode tab 11n face each other so that the positive electrode tab 11p and the negative electrode tab 11n can be electrically connected between adjacent battery cells.

  The planar view shape of the plate member 20 is not limited to the above-described first to fourth embodiments. For example, as shown in FIG. 12A, two notches 22a and 22b are formed only in a region where the positive electrode tab 11p and the negative electrode tab 11n of the battery cell 10 face each other, and the upper edge of the plate member 20 is formed in a substantially W shape. It may be formed.

  Or as shown to FIG. 12B, you may form two notches 23a and 23b in the area | region where the positive electrode tab 11p of the battery cell 10 and the negative electrode tab 11n oppose both ends of the short side of the upper side of the board | plate material 20. As shown in FIG.

  Alternatively, as illustrated in FIG. 13A, the notch 24 may be formed only in the region of the plate member 20 where the positive electrode tab 11p and the negative electrode tab 11n that are electrically connected to each other between the two adjacent battery cells 10 face each other. In this example, every other plate member 20 having notches 24 formed in only one end of the upper short side is turned over and stacked with the battery cell 10. FIG. 13B is a front view of the battery stack 1 formed as described above.

  In order to electrically connect the positive electrode tab 11p and the negative electrode tab 11n between two battery cells 10 adjacent to each other with the plate material 20 interposed therebetween, a notch formed by cutting off a part of the side of the plate material 20 is not formed. A through hole may be formed in the plate member 20.

  A so-called chamfer may be formed by cutting off the corners of the plate member 20 in a straight line shape or an arc shape. Moreover, you may form a through-hole in the board | plate material 20 further as needed.

  Measures may be taken to prevent short-circuiting between the positive electrode tab 11p and the negative electrode tab 11n that are not connected but are opposed in the stacking direction. Such a short-circuit prevention measure is not particularly limited, and for example, a known method such as covering the positive electrode tab 11p and the negative electrode tab 11n connected to each other with an insulating material may be employed.

  The number of battery cells and the number of plate members constituting the battery stack are not limited to the above embodiment, and can be arbitrarily set.

  The field of application of the present invention is not particularly limited, and is widely used as a battery laminate used for power sources of various mobile devices such as automobiles, motorcycles, and electrically assisted bicycles, personal digital assistants, and uninterruptible power supplies (UPS). be able to. In particular, it can be preferably used as a battery laminate mounted on various mobile devices that are susceptible to shock and vibration.

DESCRIPTION OF SYMBOLS 1 Battery laminated body 10 Battery cell 11p Positive electrode tab 11n Negative electrode tab 20 Plate material 21,22a, 22b, 23a, 23b, 24 Notch 25 The rectangle of the minimum area which encloses a plate material (contour rectangle)
27 Through-hole formed in plate material (thickness increase absorption means)
28 Thin-walled part (thickness increase absorption means) formed on the plate material
31, 32 Buffer member (thickness increase absorption means)

Claims (4)

A plurality of thin plate-like battery cells and a plurality of plate materials are battery stacks in which battery cells and plate materials are alternately arranged and stacked,
Each of the plurality of battery cells is directly or indirectly fixed to an adjacent plate material,
The battery laminate, wherein the plate member is provided with a thickness increasing absorption means capable of absorbing an increase in thickness of the battery cell.   The battery stack according to claim 1, wherein the thickness increase absorption means includes a through hole or a thin portion formed in a region of the plate material facing the battery cell.   The battery stack according to claim 1, wherein the thickness increase absorbing means includes a compression-deformable buffer member provided between the plate member and the battery cell.   The battery according to claim 1, wherein a notch is formed in a region of the plate material facing the positive electrode tab and / or the negative electrode tab so that the positive electrode tab and the negative electrode tab can be electrically connected between adjacent battery cells. Laminated body.

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