Battery, and battery pack

Abstract

To provide a battery capable of ensuring the strength of the terminal while improving the structural efficiency around the terminal and current collector.SOLUTION: A disclosed battery includes an electrode laminate, a current collector, and a terminal. The electrode laminate is electrically connected to the terminal via the current collector. The terminal has a base, a protrusion, and an opening. The protrusion protrudes from the base toward the electrode laminate. The shape of the opening is defined by the protrusion. The current collector is inserted into the opening and connected to the terminal. A portion of the protrusion is thicker than another portion of the protrusion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present application discloses a battery and a battery assembly. [Background technology]

[0002] Patent Document 1 discloses a technology for a battery in which an electrode stack and a lid terminal are electrically connected via a current collecting part, an outer casing is bonded to the outer periphery of the lid terminal, and the current collecting part and the electrode stack are housed inside the outer casing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-084066 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional batteries have room for improvement in terms of improving the structural efficiency around the terminals and current collectors while ensuring the strength of the terminals. [Means for solving the problem]

[0005] The present application discloses the following aspects as means for solving the above problems. <Aspect 1> A battery having an electrode stack, a current collector, and a terminal, the electrode stack is electrically connected to the terminal via the current collecting portion, the terminal has a base, a protrusion, and an opening; the protruding portion protrudes from the base portion toward the electrode stack, the shape of the opening is defined by the protrusion; the current collecting portion is inserted into the opening and connected to the terminal; a portion of the protrusion that is thicker than another portion of the protrusion; battery. <Aspect 2> 2. The battery of embodiment 1, The opening has a rectangular shape, the rectangle has first and second sides opposed to each other and third and fourth sides opposed to each other, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion constitutes the first side, the second protrusion constitutes the second side, the third protrusion constitutes the third side, the fourth protrusion constitutes the fourth side, The first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion. battery. <Aspect 3> 3. The battery of embodiment 1 or 2, The opening has a rectangular shape, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion constitutes one short side of the rectangle, the second protrusion constitutes the other short side of the rectangle; the third protrusion constitutes one long side of the rectangle, the fourth protrusion constitutes the other long side of the rectangle; The first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion. battery. <Aspect 4> 4. The battery of embodiment 3, The stacking direction of the electrode stack is along the short side, The width direction of the electrode stack is along the long side. battery. <Aspect 5> The battery of any one of Aspects 1 to 4, The protrusion protrudes from the outer edge of the base. battery. <Aspect 6> The battery of any one of Aspects 1 to 5, The planar shape of the base is rectangular, the rectangle has first and second sides opposed to each other and third and fourth sides opposed to each other, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protruding portion protrudes from the first side, the second protruding portion protrudes from the second side, the third protruding portion protrudes from the third side, the fourth protrusion protrudes from the fourth side, The first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion. battery. <Aspect 7> The battery of any one of Aspects 1 to 6, The planar shape of the base is rectangular, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion protrudes from one short side of the rectangle, the second protrusion protrudes from the other short side of the rectangle, the third protrusion protrudes from one long side of the rectangle, the fourth protrusion protrudes from the other long side of the rectangle, The first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion. battery. <Aspect 8> 8. The battery of embodiment 7, The stacking direction of the electrode stack is along the short side, The width direction of the electrode stack is along the long side. battery. <Aspect 9> The battery of any one of Aspects 1 to 8, The ratio of the width of the current collecting portion to the width of the opening is 0.9 or more. battery. <Aspect 10> The battery of any one of Aspects 1 to 9, The thickness of the base portion is smaller than the protrusion length of the protrusion portion. battery. <Aspect 11> The battery of any one of Aspects 1 to 10, The thickness of the terminal is smaller than the thickness of the electrode stack. battery. <Aspect 12> The battery of any one of Aspects 1 to 11, the base has a first surface and a second surface; the first surface faces the electrode stack, the second surface faces the opposite side to the first surface, The current collecting portion is joined to the first surface of the base. battery. <Aspect 13> 13. The battery of embodiment 12, a bus bar connected to the second surface of the base; battery. <Aspect 14> 14. The battery of embodiment 12 or 13, A portion of the current collecting portion is ultrasonically bonded or laser bonded to the first surface of the base. battery. <Aspect 15> The battery of any one of Aspects 1 to 14, The protrusion has an insulating layer on an end surface facing the electrode stack. battery. <Aspect 16> The battery of any one of Aspects 1 to 15, the protrusion has an outer surface and an inner surface; the electrode stack and the current collecting portion are housed in a laminate exterior body, The laminate exterior is adhered to the outer surface of the protrusion. battery. <Aspect 17> A battery pack comprising a plurality of batteries and at least one bus bar; the bus bar electrically connects one of the batteries to another of the batteries; one or both of the one battery and the other battery has an electrode stack, a current collector, and a terminal; the electrode stack is electrically connected to the terminal via the current collecting portion, the terminal has a base, a protrusion, and an opening; The base portion is a first surface facing the electrode stack; a second surface facing the opposite side to the first surface and to which the bus bar is connected; and the protruding portion protrudes from the first surface of the base portion toward the electrode stack, the shape of the opening is defined by the protrusion; The current collecting portion is inserted into the opening and connected to the terminal. Battery pack. <Aspect 18> The battery pack of embodiment 17, The bus bar has a slit. Battery pack. [Effects of the Invention]

[0006] According to the battery of the present disclosure, the structural efficiency around the terminals and current collectors is likely to be improved (space is likely to be saved), and the strength of the terminals is likely to be ensured. [Brief explanation of the drawings]

[0007] [Figure 1] 1 shows a schematic diagram of an example of the external configuration of a battery. [Figure 2] 2 shows a schematic diagram of an example of a cross section taken along the line II-II of FIG. 1. [Figure 3] 2 shows a schematic diagram of an example of a cross section taken along the line III-III in FIG. 1. [Figure 4] 4 shows a schematic diagram of an example of a cross section taken along the line IV-IV in FIG. 1. [Figure 5] 2A and 2B are diagrams illustrating an example of the external shape of a terminal. [Figure 6] 2A and 2B are schematic diagrams illustrating an example of a cross-sectional shape of a terminal. [Figure 7]2A and 2B are schematic diagrams illustrating an example of a cross-sectional shape of a terminal. [Figure 8] 10A and 10B are schematic diagrams illustrating examples of the tip shape and opening shape of the protrusion. [Figure 9] 2A and 2B are schematic diagrams illustrating an example of a cross-sectional shape of a terminal. [Figure 10] 10 is a schematic diagram showing an example of a cross-sectional shape when an insulating layer is provided on a part of a terminal. [Figure 11] 1 is a schematic diagram illustrating an example of a bonding configuration between a terminal and an exterior body, with the current collector and electrode stack omitted. [Figure 12] 1 is a schematic diagram illustrating an example of the external configuration of a battery pack, showing only the configuration in the vicinity of the terminals and bus bars. [Figure 13] 10 is a schematic diagram illustrating an example of a state in which a probe is pressed against a terminal. [Figure 14] The analysis results for the amount of heat generated by current flow around the terminals are shown. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, one embodiment of the battery of the present disclosure will be described, but the battery of the present disclosure is not limited to the following embodiment.

[0009] As shown in FIGS. 1 to 8 , a battery 100 according to one embodiment has an electrode stack 10, a current collector 20, and a terminal 30. The electrode stack 10 is electrically connected to the terminal 30 via the current collector 20. The terminal 30 has a base 31, a protruding portion 32, and an opening 33. The protruding portion 32 protrudes from the base 31 toward the electrode stack 10. The shape of the opening 33 is defined by the protruding portion 32. The current collector 20 is inserted into the opening 33 and connected to the terminal 30. A portion of the protruding portion 32 is thicker than another portion of the protruding portion 32.

[0010] 1. Electrode laminate The battery 100 supplies the power generated in the electrode stack 10 to an external device or the like via the current collecting parts 20 and the terminals 30. That is, the electrode stack 10 functions as the power generating element of the battery 100.

[0011] As shown in FIGS. 2 and 4 , the electrode stack 10 may be formed by stacking multiple electrode bodies. Each electrode body may include, for example, a layer made of a positive electrode current collector, a layer made of a positive electrode active material layer, an electrolyte layer, a layer made of a negative electrode active material layer, and a layer made of a negative electrode current collector. Known positive electrode current collectors, positive electrode active material layers, electrolyte layers, negative electrode active material layers, and negative electrode current collectors may be used. The electrode stack 10 may include a solid electrolyte, a liquid electrolyte, or both a solid electrolyte and a liquid electrolyte. When the electrode stack 10 includes at least a solid electrolyte, a battery 100 with excellent mechanical properties, output characteristics, and the like is easily obtained. The shape of the stacking surface of each layer constituting the electrode stack 10 may be, for example, rectangular.

[0012] The number of stacked electrode bodies in the electrode stack 10 is not particularly limited. In the electrode stack 10, the multiple electrode bodies may be connected to each other in series or in parallel. The electrode stack 10 may have a bipolar structure. Furthermore, in the electrode stack 10, the stacking surfaces of the electrode bodies may be insulated from each other by providing an insulating layer between one electrode body and another electrode body, for example. As shown in FIG. 2, in the battery 100, the multiple electrode bodies can be electrically connected to each other by the current collecting section 20. For example, the multiple electrode bodies can be electrically connected to each other in parallel by the current collecting section 20.

[0013] As shown in FIGS. 2 to 4 , the electrode stack 10 may have one end face 10x at one end of each layer in the stacking direction, another end face 10y at the other end of the stacking direction, and a side face 10z connecting the one end face 10x and the other end face 10y. The side face 10z may be formed by the outer edge of each layer constituting the electrode stack 10. In the electrode stack 10, the stacking areas of the layers may differ, so the side face 10z may have irregularities or gaps. Furthermore, the side face 10z may have a surface along the stacking direction of the layers in the electrode stack 10. Furthermore, the current collecting section 20, which will be described later, may protrude from the side face 10z of the electrode stack 10 toward the terminal 30. The electrode stack 10 may be, for example, plate-shaped or rectangular parallelepiped-shaped as a whole.

[0014] As shown in FIGS. 2 and 4, the electrode stack 10 has a thickness T 10 The electrode stack 10 may have a thickness T 10 is not particularly limited. 10 may be, for example, 5 mm or more and 100 mm or less, or 10 mm or more and 50 mm or less.

[0015] As shown in FIGS. 3 and 4, the electrode stack 10 has a width W along the stacking surface at the side surface 10z from which the current collecting portion 20 protrudes. 10 The electrode stack 10 may have a width W 10 is not particularly limited. 10 may be, for example, 10 mm or more and 500 mm or less, or 50 mm or more and 200 mm or less.

[0016] 2. Current collecting section The current collecting part 20 protrudes from the electrode stack 10 toward the terminal 30, and electrically connects the electrode stack 10 and the terminal 30. More specifically, as shown in Figures 2 and 3, a part of the current collecting part 20 including the tip on the terminal 30 side can be inserted into an opening 33 of the terminal 30, and a part of the current collecting part 20 can be connected to the surface of the terminal 30.

[0017] 2 and 3, the current collecting part 20 may be, for example, a bundle of multiple current collectors protruding from the side surface 10z of the electrode laminate 10 toward the terminal 30. The number of current collectors protruding in the same direction from the electrode laminate 10 is not particularly limited and may be, for example, 10 to 200, or 30 to 100. In the battery 100, the current collecting part 20 may be a bundle of multiple positive electrode current collectors, or a bundle of multiple negative electrode current collectors. In the battery 100, the multiple current collectors protruding from the side surface 10z of the electrode laminate 10 toward the terminal 30 may be bundled together, or may be separated into multiple bundles.

[0018] The current collector constituting the current collecting unit 20 may be, for example, a metal foil or a metal mesh. From the viewpoint of excellent handleability, the current collecting unit 20 may include multiple metal foils. Examples of metals constituting the current collector include Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, and stainless steel. The current collector may have a coating layer on its surface for the purpose of adjusting resistance, etc. Furthermore, when the current collecting unit 20 is made of multiple metal foils, some layer may be present between the multiple metal foils. The thickness of each current collector is not particularly limited. For example, it may be 0.1 μm or more, 1 μm or more, 1 mm or less, or 100 μm or less.

[0019] As shown in FIG. 3, the current collecting portion 20 has a width W 20 The current collecting portion 20 may have a width W 20 is not particularly limited. 20 may be, for example, 5 mm or more and 450 mm or less, or 20 mm or more and 190 mm or less.

[0020] 3. Terminals 2, 3, and 5 to 8, the terminal 30 has a base 31, a protrusion 32, and an opening 33. As shown in FIGS. 2 and 3, the surface of the terminal 30 on the electrode stack 10 side may face the inside of the battery and be connected to the current collecting part 20, and the surface opposite the electrode stack 10 may face the outside of the battery 100.

[0021] 3.1 Base As shown in FIGS. 2, 3, 6, and 7, the base 31 may have, for example, a first surface 31x facing the electrode laminate 10 and a second surface 31y facing the opposite side from the electrode laminate 10. The base 31 may correspond to, for example, the bottom of a vessel-shaped terminal 30. The first surface 31x and the second surface 31y of the base 31 may be flat as shown in the drawings, or may have irregularities. The planar shapes of the first surface 31x and the second surface 31y (referring to the planar shapes when the first surface and the second surface are projected; the same applies hereinafter) are not particularly limited. While the planar shapes of the first surface 31x and the second surface 31y shown in the drawings are rectangular, the planar shapes may be square, quadrilaterals other than rectangular (rectangles and squares), other polygonal shapes, circular, elliptical, or other shapes. In particular, when the first surface 31x and the second surface 31y are rectangular, and particularly when they are oblong, the handling properties, mechanical strength, etc. are likely to be improved. Note that the terms "polygon," "quadrilateral," "rectangle," and "rectangle" used in this application each include concepts such as shapes with chamfered corners and shapes with rounded corners.

[0022] As shown in FIGS. 6 and 7, the base 31 has a thickness T 31 (thickness from the first surface 31x to the second surface 31y). 31 is not particularly limited. In particular, the thickness T 31 When the thickness is 0.1 mm or more and 10 mm or less, or 0.2 mm or more and 3 mm or less, the terminal 30 tends to have an excellent balance of strength, heat capacity, and the like.

[0023] As shown in FIG. 6, the base 31 has a length (height) L 1 in the stacking direction of the electrode stack 10 in the inner dimension of the first surface 31x (from the inner surface of one protruding portion 32c to the inner surface of the other protruding portion 32d). 31x As shown in FIG. 6, the length L 31x is the height H of the opening 33 of the terminal 30 33 Alternatively, the length L of the first surface 31x of the base 31 may be the same as the length L of the first surface 31x of the base 31. 31x is the height H 33 The length L of the first surface 31x of the base 31 in the inner dimension may be smaller or larger than 31x is not particularly limited, and may be 4.8 mm or more and 99.8 mm or less, or 9.8 mm or more and 49.8 mm or less.

[0024] As shown in FIG. 6, the base 31 has a length (height) L 31y As shown in FIG. 7, the base 31 may have a length L 31y is the thickness T of the terminal 30 30 (the length from the outer surface of one protrusion 32c to the outer surface of the other protrusion 32d). 31y is the thickness T of the terminal 30 30 9, the protrusion 32 may protrude from inside the outer edge of the first surface 31x of the base 31 toward the electrode stack 10. 31y is the above length L 31x The thickness T 10 The length L of the base 31 at the second surface 31y may be smaller than 31y is not particularly limited, and may be 4.9 mm or more and 99.9 mm or less, or 9.9 mm or more and 49.9 mm or less.

[0025] As shown in FIG. 7, the base 31 has an inner dimension of the first surface 31x that is a width W along the stacking surface of the electrode stack 10. 31xAs shown in FIG. 7, the width W 31x is the width W of the opening 33 of the terminal 30 33 Alternatively, the width W of the first surface 31x of the base 31 may be the same as the inner dimension of the width W 31x is the width W 33 It may be smaller than the width W 31x is the width W mentioned above 20 It may be larger than the width W 31x is the width W described below 31y The width W of the first surface 31x of the base 31 at the inner dimension may be smaller than the above. 31x is not particularly limited, and may be 7.5 mm or more and 475 mm or less, or 30 mm or more and 195 mm or less.

[0026] As shown in FIG. 7, the base 31 has a width W 31y As shown in FIG. 7, the width W 31y is the width W of the opening 33 of the terminal 30 33 and the thickness T of the protrusion 32 32 (T 32a and T 32b ) and the width W of the second surface 31y of the base 31. 31y is the width W 33 and thickness T 32 The width W 31y is the width W 31x and width W 33 It may be larger than the width W 31y is the width W 10 The width W of the second surface 31y of the base 31 may be smaller than 31y is not particularly limited, and may be 8.1 mm or more and 475.1 mm or less, or 30.1 mm or more and 195.1 mm or less.

[0027] On the first surface 31x of the base 31, the length (height) L 31x and width W 31x Relative to L 31x / W 31x is not particularly limited. In particular, the ratio L31x / W 31x When the ratio is 0.01 or more and 13.3 or less, or 0.05 or more and 1.66 or less, the terminal tends to have an excellent balance between strength, heat capacity, and the like.

[0028] On the second surface 31y of the base 31, the length (height) L 31y and width W 31y Relative to L 31y / W 31y is not particularly limited. In particular, the ratio L 31y / W 31y When the ratio is 0.01 or more and 13.3 or less, or 0.05 or more and 1.66 or less, the terminal tends to have an excellent balance between strength, heat capacity, and the like.

[0029] 3.2 Protrusion The protrusion 32 protrudes from the base 31 toward the electrode stack 10. As shown in Figures 2, 3, and 5 to 8, at least a part of the protrusion 32 may protrude linearly from the base 31 toward the electrode stack 10 while having a certain thickness.

[0030] In the battery 100, it is important that a portion of the protrusion 32 is thicker than the remaining portion of the protrusion 32. The "thickness of the protrusion" referred to herein is measured at the end face of the protrusion facing the electrode laminate. By partially varying the thickness of the protrusion 32, the thinner portion of the protrusion 32 ensures space for joining the current collector 20, while the thicker portion of the protrusion 32 ensures the strength and heat capacity of the terminal 30. That is, by making a portion of the protrusion 32 thicker than the remaining portion of the protrusion 32, the area around the terminal 30 and the current collector 20 can be easily reduced and the strength of the terminal 30 can be easily ensured. Furthermore, when only a portion of the protrusion 32 is thick, the heat capacity of the terminal 30 as a whole is reduced compared to when the entire protrusion 32 is thick, and the heat sealability of the laminate exterior body, as described below, is improved. Furthermore, when only a portion of the protrusion 32 is thin, the strength of the protrusion 32 is ensured, and the heat capacity is ensured, making it easier to suppress heat generation when current is applied, compared to when the entire protrusion 32 is thin. 32(For example, T in Figures 6 to 8 32a ~T 32d ) is not particularly limited, and may be 0.1 mm or more and 10 mm or less, or 0.2 mm or more and 3 mm or less.

[0031] In the terminal 30, the thickness T of the thickest part of the protrusion 32 max (For example, thickness T in Figs. 7 and 8 32a or T 32b ) is not particularly limited, and may be more than 0.1 mm and not more than 10 mm, or more than 0.2 mm and not more than 3 mm. min (For example, thickness T in Figs. 6 and 8 32c or T 32d ) is not particularly limited, and may be 0.1 mm or more and less than 10 mm, or 0.2 mm or more and less than 3 mm. max and the thickness of the thinnest part T min Relative to T max / T min may be greater than 1.0 and equal to or less than 10, or equal to or greater than 1.5 and equal to or less than 5.

[0032] In the terminal 30, the thickness T of the base 31 31 and the maximum thickness T of the protrusion 32 max Relative to T 31 / T max is not particularly limited. In particular, the ratio T 31 / T max When the ratio is 0.1 or more and 5 or less, or 0.3 or more and 1 or less, the terminal 30 tends to have an excellent balance of strength, heat capacity, and the like.

[0033] As shown in FIGS. 6 and 7, the protrusion 32 extends from the first surface 31x of the base 31 toward the electrode stack 10 by a protrusion length L 32 The protrusion 32 may have a protrusion length L 32 is not particularly limited, and may be 3 mm or more and 50 mm or less, or 5 mm or more and 30 mm or less. 32That is, the protrusion 32 may be flush with the electrode stack 10. Alternatively, the protrusion length of a portion of the protrusion 32 may be different from the protrusion length of the other portion.

[0034] As shown in FIGS. 6 and 7, the thickness T 31 is the protrusion length L of the protrusion 32 32 The thickness T of the base 31 may be smaller than 31 By making the thickness T of the base 31 relatively thin, the space for inserting the current collecting part 20 becomes larger and the heat capacity of the terminal 30 can be reduced, which, for example, makes it easier to improve the heat sealing property of the laminate exterior body to the terminal 30. 31 and the protruding length L of the protruding portion 32 32 Relative to T 31 / L 32 may be, for example, greater than 0 and less than 1.0, 0.02 or greater and 0.5 or less, or 0.05 or greater and 0.25 or less.

[0035] 2, 3, and 5 to 8, in the terminal 30, the protrusion 32 may protrude from the outer edge of the base 31. That is, the planar shape of the second surface 31y of the base 31 may coincide with the shape defined by the outer periphery of the protrusion 32. Alternatively, as shown in FIG. 9, the protrusion 32 may protrude from inside the outer edge of the first surface 31x of the base 31. That is, the planar shape of the second surface 31y of the base 31 may be larger than the shape defined by the outer periphery of the protrusion 32.

[0036] When the protrusion 32 protrudes from the outer edge of the base 31, the shape defined by the outer periphery of the protrusion 32 corresponds to the planar shape of the second surface 31y of the base 31. For example, when the planar shape of the base 31 (the planar shape of the second surface 31y) is rectangular and the rectangle has a first side and a second side facing each other and a third side and a fourth side facing each other, the protrusion 32 may have a first protrusion 32a, a second protrusion 32b, a third protrusion 32c, and a fourth protrusion 32d, where the first protrusion 32a protrudes from the first side, the second protrusion 32b protrudes from the second side, the third protrusion 32c protrudes from the third side, and the fourth protrusion 32d protrudes from the fourth side. In this case, the protrusions constituting the two opposing sides may be thicker than the protrusions constituting the other two sides. For example, as shown in Figures 5 to 8, the first protrusion 32a and the second protrusion 32b may be thicker than the third protrusion 32c and the fourth protrusion 32d. In this way, the thickness of the protrusions 32a and 32b protruding from two opposing sides is thicker than the thickness of the protrusions 32c and 32d protruding from the other two sides, which tends to provide a good balance between the strength and heat capacity of the terminal 30 as a whole. Furthermore, when a laminate exterior body is used as the exterior body 40 described below, the terminal 30 having a well-balanced heat capacity allows the terminal 30 and the laminate exterior body to be heated appropriately, improving the heat-sealing properties of the laminate exterior body to the terminal 30. Furthermore, the terminal 30 having a well-balanced heat capacity tends to suppress heat generation in the terminal 30 when current is applied. In this case, the thicknesses of the protrusions 32a and 32b protruding from the two opposing sides may be the same (within an error of 0.1 mm), and the thicknesses of the protrusions 32c and 32d protruding from the other two opposing sides may be the same (within an error of 0.1 mm).

[0037] Furthermore, for example, when the planar shape of the base 31 (planar shape of the second surface 31y) is rectangular, the protrusion 32 may have a first protrusion 32a, a second protrusion 32b, a third protrusion 32c, and a fourth protrusion 32d, where the first protrusion 32a protrudes from one short side of the rectangle, the second protrusion 32b protrudes from the other short side of the rectangle, the third protrusion 32c protrudes from one long side of the rectangle, and the fourth protrusion 32d protrudes from the other long side of the rectangle. In this case, too, the protrusions constituting the two opposing sides may be thicker than the protrusions constituting the other two sides. In particular, a more excellent effect can be expected when the protrusions on the short sides are thicker than the protrusions on the long sides. That is, the first protrusion 32a and the second protrusion 32b may be thicker than the third protrusion 32c and the fourth protrusion 32d. By making the protruding portions on the short sides thicker than the protruding portions on the long sides, it is possible to ensure a large space for inserting the current collecting part 20, while also easily achieving a good balance between the strength and heat capacity of the terminal 30 as a whole. Furthermore, when a laminate exterior body is used as the exterior body 40 described below, the terminal 30 having a good balance of heat capacity allows the terminal 30 and the laminate exterior body to be heated appropriately, improving the heat-sealing properties of the laminate exterior body to the terminal 30. Furthermore, by making the terminal 30 having a good balance of heat capacity, it is possible to easily suppress heat generation in the terminal 30 when current is applied. In this case, the thicknesses of the protruding portions 32a, 32b protruding from the short sides may be the same (within a tolerance of 0.1 mm), and the thicknesses of the protruding portions 32c, 32d protruding from the long sides may be the same (within a tolerance of 0.1 mm).

[0038] Furthermore, when the planar shape of the base 31 (the planar shape of the second surface 31y) is rectangular, the stacking direction in the electrode laminate 10 may be along the short side of the rectangle, and the width direction of the electrode laminate 10 may be along the long side of the rectangle. This makes it easy to ensure a large space for inserting the current collecting part 20, and also makes it easy to achieve an excellent balance between the strength and heat capacity around the terminal 30 and the current collecting part 20.

[0039] 3.3 Aperture The current collecting portion 20 is inserted into the opening 33 and connected to the terminal 30. The shape of the opening 33 is defined by the protrusion 32. The shape of the opening 33 is not particularly limited. The shape of the opening 33 may be rectangular, circular, elliptical, or any other shape.

[0040] When the opening 33 is rectangular and has a first side and a second side facing each other and a third side and a fourth side facing each other, the protrusion 32 may have a first protrusion 32a, a second protrusion 32b, a third protrusion 32c, and a fourth protrusion 32d, where the first protrusion 32a constitutes the first side, the second protrusion 32b constitutes the second side, the third protrusion 32c constitutes the third side, and the fourth protrusion 32d constitutes the fourth side. In this case, the protrusions constituting the two opposing sides may be thicker than the protrusions constituting the other two sides. For example, as shown in FIGS. 5 to 8, the first protrusion 32a and the second protrusion 32b may be thicker than the third protrusion 32c and the fourth protrusion 32d. In this way, the thickness of the protrusions 32a, 32b constituting the two opposing sides is greater than the thickness of the protrusions 32c, 32d constituting the other two sides, which tends to result in an excellent balance between the strength and heat capacity of the terminal 30 as a whole. Furthermore, when a laminate outer casing is used as the outer casing 40 described below, the terminal 30 having an excellent balance of heat capacity allows the terminal 30 and the laminate outer casing to be heated appropriately, improving the heat-sealing properties of the laminate outer casing to the terminal 30. Furthermore, the terminal 30 having an excellent balance of heat capacity tends to suppress heat generation of the terminal 30 when current is applied. In this case, the thicknesses of the protrusions 32a, 32b constituting the two opposing sides may be the same (within a tolerance of 0.1 mm), and the thicknesses of the protrusions 32c, 32d constituting the other two opposing sides may be the same (within a tolerance of 0.1 mm).

[0041] When the shape of the opening 33 is rectangular, the protrusion 32 may have a first protrusion 32a, a second protrusion 32b, a third protrusion 32c, and a fourth protrusion 32d, with the first protrusion 32a constituting one short side of the rectangle, the second protrusion 32b constituting the other short side of the rectangle, the third protrusion 32c constituting one long side of the rectangle, and the fourth protrusion 32d constituting the other long side of the rectangle. In this case, too, the protrusions constituting the two opposing sides may be thicker than the protrusions constituting the other two sides. In particular, a more excellent effect can be expected if the protrusions on the short sides are thicker than the protrusions on the long sides. That is, the first protrusion 32a and the second protrusion 32b may be thicker than the third protrusion 32c and the fourth protrusion 32d. In this way, the thickness of the protrusions 32a, 32b constituting the short sides is thicker than the thickness of the protrusions 32c, 32d constituting the long sides, which tends to result in an excellent balance between the strength and heat capacity of the terminal 30 as a whole. Furthermore, when a laminate exterior body is used as the exterior body 40 described below, the terminal 30 having an excellent balance of heat capacity allows the terminal 30 and the laminate exterior body to be heated appropriately, improving the heat-sealing properties of the laminate exterior body to the terminal 30. Furthermore, the terminal 30 having an excellent balance of heat capacity tends to suppress heat generation of the terminal 30 when current is applied. In this case, the thicknesses of the protrusions 32a, 32b constituting the short sides may be the same (within a tolerance of 0.1 mm), and the thicknesses of the protrusions 32c, 32d constituting the long sides may be the same (within a tolerance of 0.1 mm).

[0042] Furthermore, when the shape of the opening 33 is rectangular, the stacking direction in the electrode stack 10 may be along the short side of the rectangle, and the width direction of the electrode stack 10 may be along the long side of the rectangle. This makes it easy to ensure a large space for inserting the current collecting part 20, and also makes it easy to achieve an excellent balance of strength and heat capacity around the terminal 30 and the current collecting part 20.

[0043] As shown in FIGS. 6 and 8, the opening 33 has a height H 33 The height H of the opening 3333 is not particularly limited. For example, the height H 33 is the length L 31x The height H 33 is the length L 31y It may be smaller than the height H 33 is the thickness T 10 In particular, the height H of the opening 33 33 When the opening 33 is 4.8 mm or more and 99.8 mm or less, or 9.8 mm or more and 49.8 mm or less, the strength of the terminal 30 is easily ensured, and the insertion of the current collecting part 20 into the opening 33 and the joining of the current collecting part 20 to the terminal 30 are made easier.

[0044] As shown in FIGS. 7 and 8, the opening 33 has a width W 33 The width W of the opening 33 33 is not particularly limited. 33 is the width W 20 Larger than width W 33 is the width W 31x It may be the same as the width W 33 is the width W 31y The width W 33 is the width W 10 In particular, the width W of the opening 33 33 When the width W of the current collecting portion 20 is 7.5 mm or more and 475 mm or less, or 30 mm or more and 195 mm or less, the strength of the terminal 30 is easily ensured, and 20 is easily secured.

[0045] Height H of opening 33 33 and width W 33 Relative to H 33 / W 33 is not particularly limited. In particular, the ratio H 33 / W 33 When the ratio is 0.01 or more and 13.3 or less, or 0.05 or more and 1.66 or less, the current collecting portion 20 is likely to be easily joined, and the terminal 30 is likely to have an excellent balance between strength and heat capacity.

[0046] 3.4 Other matters regarding terminals Terminal 30, which includes base 31, protrusion 32, and opening 33, can be easily manufactured by, for example, press-forming metal. For example, by applying pressure to one surface of a metal rectangular parallelepiped to form a recess, protrusion 32 can be formed around the recess. In this case, the bottom of the recess corresponds to base 31, and the opening of the recess corresponds to opening 33.

[0047] The material of the terminal 30 may be appropriately selected taking into consideration sufficient conductivity, appropriate heat capacity, appropriate mechanical strength, etc. For example, the material of the terminal 30 may be aluminum, copper, iron, nickel, or an alloy thereof. The terminal 30 may be formed by plating any of the above metals or alloys onto a substrate.

[0048] An insulating layer may be provided between the terminal 30 and the electrode stack 10. This further facilitates suppression of short circuits and the like in the battery 100. For example, as shown in FIG. 10 , the protruding portion 32 of the terminal 30 may have an insulating layer 35 on the end surface facing the electrode stack 10. For example, the insulating layer 35 can be formed on the end surface of the protruding portion 32 of the terminal 30 by applying or transferring an insulating resin material (e.g., ultraviolet-curable resin such as an acrylic monomer / oligomer; thermosetting resin such as an epoxy resin or an imide resin; or thermoplastic resin such as polypropylene or polyethylene) to the end surface of the protruding portion 32 of the terminal 30, or by forming a layer made of a metal oxide (e.g., aluminum oxide) on the end surface by anodizing or the like. The thickness of the insulating layer 35 is not particularly limited. When the insulating layer 35 is made of an insulating resin material, its thickness may be, for example, 0.1 mm or more and 1.0 mm or less. When the insulating layer 35 is made of a metal oxide formed by anodizing or the like, its thickness may be, for example, 0.01 mm or more and less than 0.10 mm.

[0049] 4. Supplementary information on the arrangement of electrode laminates, current collectors, and terminals In the battery 100, there are no particular limitations on the arrangement of the electrode laminate 10, the current collecting parts 20, and the terminals 30, as long as the current collecting parts 20 protruding from the electrode laminate 10 are inserted into the openings 33 of the terminals 30 and are electrically connected to the terminals 30. In the battery 100, by employing terminals 30 having the above-described specific shapes, it is easy to save space around the terminals 30 and the current collecting parts 20, it is easy to ensure the strength of the terminals 30, and it is easy to make the terminals 30 have an excellent balance of heat capacity. Below, a supplementary explanation of an example of the arrangement of the electrode laminate 10, the current collecting parts 20, and the terminals 30 will be provided.

[0050] 4.1 Terminal width and current collecting part width As described above, the current collecting portion 20 protruding from the electrode laminate 10 is inserted into the opening 33 of the terminal 30 and connected to the surface of the terminal 30, thereby enabling power to be supplied from the electrode laminate 10 to an external device via the current collecting portion 20 and the terminal 30. Here, when a large current flows through the current collecting portion 20 and the terminal 30, heat may be generated in the current collecting portion 20 and the terminal 30. According to the knowledge of the present inventors, the heat generation temperature around the terminal 30 and the current collecting portion 20 varies depending on the width of the current collecting portion 20 relative to the width of the terminal 30. As shown in FIG. 3 , for example, when the width W of the opening 33 of the terminal 30 is 33 Width W of the current collecting part 20 20 Ratio of W 20 / W 33 When the inner width W of the base 31 of the terminal 30 is 0.9 or more, it is possible to significantly suppress heat generation around the terminal 30 and the current collecting portion 20. 31x Width W of the current collecting portion 20 relative to (width of the inner dimension of the first surface 31x) 20 Ratio of W 20 / W 31x Similarly, when the ratio is 0.9 or more, heat generation around the terminal 30 and the current collecting portion 20 can be significantly suppressed.

[0051] 4.2 Electrode laminate thickness and terminal thickness Thickness T of terminal 30 30 is the thickness T of the electrode laminate 10 10 In particular, as shown in FIG. 2, the thickness T30 However, if the thickness is thinner than the thickness of the electrode laminate 10, it becomes easier to further improve the adhesion between the exterior body and the terminal 30 by, for example, placing resin 34 between the laminate exterior body and the terminal 30.

[0052] 4.3 Joint configuration between current collector and terminal As described above, the current collecting part 20 is connected to the terminal 30. For example, the current collecting part 20 may be joined to the terminal 30 to form a joint 25. More specifically, as shown in FIGS. 2 and 3 , in a case where the base 31 of the terminal 30 has a first surface 31x and a second surface 31y, the first surface 31x faces the electrode stack 10, and the second surface 31y faces the side opposite to the first surface 31x, the current collecting part 20 may be joined to the first surface 31x of the base 31. In one embodiment, a portion of the current collecting part 20 may be ultrasonically or laser-joined to the first surface 31x of the base 31.

[0053] 5. Other materials The battery 100 may include other obvious components of a battery in addition to the electrode stack 10, the current collector 20, and the terminal 30. For example, various components such as those disclosed in Patent Document 1 (JP 2023-084066 A) may be employed as other components. An example of other components included in the battery 100 will be described below.

[0054] 5.1 Exterior The battery 100 may have an exterior body 40 that houses the electrode stack 10 and the current collecting unit 20. The exterior body may be made of a laminate film (laminated exterior body) or may be made of a metal case. As shown in the figure, when the protrusion 32 has an outer surface (the surface opposite to the space into which the current collecting unit 20 is inserted) and an inner surface (the surface facing the space into which the current collecting unit 20 is inserted), the electrode stack 10 and the current collecting unit 20 may be housed in a laminate exterior body, and the laminate exterior body may be bonded to the outer surface of the protrusion 32.

[0055] The exterior body 40 may be, for example, a cylindrical body having an opening. That is, as shown in Figures 2 and 3, the electrode stack 10 and the current collecting part 20 are housed inside the cylindrical exterior body 40, and the outer surface of the protrusion 32 of the terminal 30 can be adhered and sealed near the opening of the exterior body 40. In this case, as shown in Figures 2 and 3, the vicinity of the opening of the exterior body 40 and the protrusion 32 of the terminal 30 can be adhered so as to overlap each other when viewed in the stacking direction of the electrode stack 10. This can improve the sealing performance of the battery 100 and the structural efficiency around the terminal 30.

[0056] As shown in FIG. 11, the length L between the opening 33 of the terminal 30 and the opening 41 of the exterior body 40 41 is not particularly limited. In particular, the length L 41 When the protrusion length L of the protrusion 32 is 1.0 mm or more and 20 mm or less, or 3.0 mm or more and 15 mm or less, a good balance between sealing performance and structural efficiency is likely to be achieved. 32 The above length L 41 The ratio of L 41 / L 32 In particular, the ratio L 41 / L 32 When the ratio is 0.1 or more and 1.0 or less, or 0.5 or more and 1.0 or less, a good balance between sealing performance and structural efficiency is likely to be achieved. When the exterior body 40 is a laminate exterior body, the laminate exterior body may be bonded to the outer surface of the protrusion 32 by heat sealing or the like, for example. When the exterior body 40 is a metal case, the metal case may be bonded to the outer peripheral surface of the protrusion 32 by welding or using an adhesive, for example. As described above, a resin 34 may be disposed between the outer surface of the protrusion 32 and the exterior body 40.

[0057] 5.2 Busbars The battery 100 may include a conductive member for connecting one battery to another. For example, in the battery 100, a bus bar may be connected to the terminal 30. More specifically, when the base 31 has a first surface 31x and a second surface 31y, the first surface 31x faces the electrode stack 10 and the second surface 31y faces the side opposite to the first surface 31x, and the current collecting section 20 is joined to the first surface 31x of the base 31, a bus bar may be connected to the second surface 31y of the base 31. A plurality of batteries 100 may be combined to form an assembled battery. An example of an assembled battery is shown below.

[0058] 6. Battery pack As shown in FIG. 12 , a battery pack 1000 according to one embodiment includes a plurality of batteries 100a and 100b and at least one bus bar 200. The bus bar 200 electrically connects one battery 100a to another battery 100b. One or both of the battery 100a and the other battery 100b includes an electrode stack 10, a current collector 20, and a terminal 30. The electrode stack 10 is electrically connected to the terminal 30 via the current collector 20. The terminal 30 includes a base 31, a protrusion 32, and an opening 33. The base has a first surface 31x facing the electrode stack 10 and a second surface 31y facing the opposite side from the first surface 31x and to which the bus bar 200 is connected. The protrusion 32 protrudes from the first surface 31x of the base 31 toward the electrode stack 10. The shape of the opening 33 is defined by the protrusion 32. The current collecting part 20 is inserted into the opening 33 and connected to the terminal 30.

[0059] As in the battery pack 1000, connecting the bus bar 200 to the second surface 31y of the terminal 30 tends to increase the connection area between the terminal 30 and the bus bar 200, thereby suppressing heat generation between the terminal 30 and the bus bar 200. This heat generation suppression effect is also achieved when the thickness of the protruding portion 32 of the terminal 30 is constant. However, from the viewpoint of ensuring sufficient strength of the terminal 30 and further improving the connection reliability of the bus bar 200 to the terminal 30, it is preferable that a portion of the protruding portion 32 of the terminal 30 is thicker than the other portions.

[0060] Details of the electrode stack 10, current collector 20, and terminal 30 that may be included in the battery 100a and the battery 100b may be the same as those described above. In the battery pack 1000, one of the battery 100a and the battery 100b may be the battery 100 of the present disclosure, or both may be the batteries 100 of the present disclosure. Note that, while Fig. 12 illustrates a configuration in which two batteries 100a, 100b are electrically connected via a bus bar 200, the number of batteries in the battery pack is not limited to two and may be three or more.

[0061] 12, the bus bar 200 may include, for example, a first portion 200a that is directly or indirectly connected to a terminal of one battery 100a, a second portion 200b that is directly or indirectly connected to a terminal of another battery 100b, and a third portion 200c that connects the first portion 200a and the second portion 200b. The first portion 200a and the second portion 200b may have shapes that are symmetrical to each other. The third portion 200c may protrude from the first portion 200a and the second portion 200b on the side opposite the terminals.

[0062] The busbar 200 may have slits 200cx. The busbar 200 having the slits 200cx improves the deformation performance of the busbar 200 and improves the connection reliability of the busbar 200 to the terminals. The shape, position, and number of the slits 200cx are not limited to those shown in FIG. 12. The shape of the slits 200cx may be, for example, rectangular, circular, or another shape. When the busbar 200 has the first portion 200a, the second portion 200b, and the third portion 200c, the slits 200cx may be provided in at least the third portion 200c. The number of slits 200cx provided in one busbar 200 may be one or more.

[0063] Bus bar 200 may be made of various conductive materials. For example, bus bar 200 may be made of metal. There are no particular limitations on the thickness of bus bar 200, as long as it is an appropriate thickness that allows batteries to be electrically connected to each other.

[0064] The busbar 200 is connected to the second surface 31y of the base 31 of the terminal 30. Here, the "second surface 31y to which the busbar 200 is connected" includes not only a case in which the busbar 200 is directly connected to the second surface 31y (the busbar 200 is in contact with the second surface 31y) but also a case in which the busbar 200 is indirectly connected to the second surface 31y via some intermediate member (the busbar 200 is not in contact with the second surface 31y). The connection mode of the busbar 200 to the terminal 30 is not particularly limited. The busbar 200 may be fixed to the terminal 30 by a fixing member or the like. Alternatively, the busbar 200 may be welded to the terminal 30. Alternatively, as described above, some intermediate member may be present between the busbar 200 and the terminal 30. That is, bus bar 200 may be directly connected to one surface of the intermediate member by fixing, welding, or the like, and terminal 30 may be directly connected to the other surface of the intermediate member by fixing, welding, or the like.

[0065] 7.Applications The battery 100 and the battery pack 1000 have a wide range of applications. For example, the battery 100 and the battery pack 1000 can be suitably used in at least one type of vehicle selected from a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and an electric vehicle (BEV). That is, the technology of the present disclosure also has an aspect of a vehicle having a battery 100, the battery 100 having an electrode stack 10, a current collector 20, and a terminal 30, the electrode stack 10 being electrically connected to the terminal 30 via the current collector 20, the terminal 30 having a base 31, a protrusion 32, and an opening 33, the protrusion 32 protruding from the base 31 toward the electrode stack 10, the shape of the opening 33 being defined by the protrusion 32, the current collector 20 being inserted into the opening 33 and connected to the terminal 30, and a portion of the protrusion 32 being thicker than other portions of the protrusion 32. The technology of the present disclosure also relates to a vehicle having a battery pack 1000, the battery pack 1000 including a plurality of batteries 100a, 100b and at least one bus bar 200, the bus bar 200 electrically connecting one of the batteries 100a and another of the batteries 100b, one or both of the one of the batteries 100a and another of the batteries 100b having an electrode stack 10, a current collecting portion 20 and a terminal 30, the electrode stack 10 being electrically connected to the terminal 30 via the current collecting portion 20, and the terminal 30 has a base 31, a protrusion 32, and an opening 33, the base 31 has a first surface 31x facing the electrode stack 10 and a second surface 31y facing the opposite side to the first surface 31x and to which the bus bar 200 is connected, the protrusion 32 protrudes from the first surface 31x of the base 31 toward the electrode stack 10, the shape of the opening 33 is defined by the protrusion 32, and the current collecting portion 20 is inserted into the opening 33 and connected to the terminal 30, and also has a side surface in which the protrusion 32 protrudes from the first surface 31x of the base 31 toward the electrode stack 10, the shape of the opening 33 is determined by the protrusion 32, and the current collecting portion 20 is inserted into the opening 33 and connected to the terminal 30. [Example]

[0066] As described above, one embodiment of the battery of the present disclosure has been described, but the battery of the present disclosure can be modified in various ways other than the above embodiment without departing from the spirit of the battery. Below, the technology of the present disclosure will be described in more detail using examples, but the technology of the present disclosure is not limited to the following examples.

[0067] 1. Consideration of terminal strength To improve the structural efficiency of the battery terminals and current collectors, it is effective to provide a recess in the terminal and bond the current collector to the recess (see, for example, Figures 2 to 8). In other words, a protrusion protrudes from a base, and the current collector can be inserted into an opening defined by the protrusion. Meanwhile, battery manufacturing processes include, for example, an activation process in which a large current is passed through the battery. In this activation process, as shown in Figure 13, for example, the battery is held down with a jig, and a probe is pressed against the battery terminal to pass a large current through the battery. In order to pass a large current, the load F applied by the jig or probe is often increased, or the diameter of the probe is increased. According to the inventor's findings, when a probe is pressed against a terminal having the above-described base, protrusion, and opening during the activation process, the protrusion may buckle, causing deformation. In other words, the terminal's rigidity is likely to be insufficient, which is a tradeoff for improving the structural efficiency of the terminals and current collectors.

[0068] The inventors have studied ways to ensure the rigidity of the terminal and found that by making some parts of the terminal protrusion thicker and some parts thinner, it is possible to improve the structural efficiency and ensure the rigidity of the terminal. For example, in the case of a terminal made of an aluminum alloy, it has been found that if a part of the terminal protrusion is made 1.5 mm or thicker, deformation of the terminal can be suppressed even if a probe is pressed against the terminal with a large load (a load that can cause a large current to flow, which will significantly increase activation) during the activation process.

[0069] 2. Examination of heat sealability We investigated the heat-sealing properties of terminals when bonding laminate exterior bodies to them. We found that if the entire terminal protrusion is made thick, the terminal's heat capacity (thermal mass) becomes excessively large, making it impossible to properly heat-seal the laminate exterior body. For example, based on the results of the above-mentioned terminal strength study, we found that if the entire protrusion of an aluminum alloy terminal is made thick (for example, 1.5 mm or thicker) to ensure terminal strength, the terminal's heat capacity becomes excessively large. During heat-sealing of the laminate film, the temperature rise rate at the interface between the terminal and the laminate film slows down from around 60°C, making it difficult to reach the melting point of the laminate film resin, resulting in poor heat-sealing properties.

[0070] In contrast, by making part of the protrusion thicker while making other parts of the protrusion thinner, the thermal capacity of the terminal can be kept low, thereby achieving both structural efficiency around the terminal and the strength of the terminal, while also improving the heat sealing properties of the laminate film.

[0071] 3. Study on heat generation during power supply In batteries, it is sometimes necessary to suppress heat generation around the terminals when current is applied. For example, excessive heat generation at the terminals may adversely affect the sealing between the exterior body and the terminals. The present inventors have determined the width B of the current collecting portion protruding from the electrode laminate (width W in FIG. 3). 20 ) and the terminal inner dimension A (opening width W in Figure 3) 33We performed an analysis by varying the ratio B / A (corresponding to B / A = 0.5) to determine the ratio B / A that significantly suppresses heat generation around the terminals. We found that heat generation around the terminals can be significantly suppressed when B / A is 0.9 or greater. Figure 14 compares temperature contours for B / A = 0.5 and B / A = 0.9. In Figure 14, the battery is cooled by a cooling device from the bottom of the page. The cooling conditions for the cooling device and the battery energization conditions are the same for B / A = 0.5 and B / A = 0.9. As is clear from Figure 14, when B / A = 0.9, the temperature around the terminals during energization is lower than when B / A = 0.5, and heat generation around the terminals is significantly suppressed.

[0072] As described above, it was found that in order to suppress heat generation due to current flow around the terminal, it is effective to make the ratio of the width of the current collecting part to the width of the terminal opening 0.9 or more (or to make the ratio of the width of the current collecting part to the inner width of the base of the terminal 0.9 or more). [Explanation of symbols]

[0073] 100 batteries 10 Electrode laminate 20 Current collector 25 Joint 30 terminals 31 Base 31x 1st side 31y 2nd side 32 Protrusion 32a 1st protrusion 32b Second protrusion 32c Third protrusion 32d 4th protrusion 33 Aperture 34 Resin 35 Insulating layer 40 Exterior body 41 Aperture

Claims

1. A battery having an electrode stack, a current collector, and a terminal, the electrode stack is electrically connected to the terminal via the current collecting portion, the terminal has a base, a protrusion, and an opening; the protruding portion protrudes from the base portion toward the electrode stack, the shape of the opening is defined by the protrusion; the current collecting portion is inserted into the opening and connected to the terminal; a portion of the protrusion that is thicker than another portion of the protrusion; battery.

2. 10. The battery of claim 1, The opening has a rectangular shape, the rectangle has first and second sides opposed to each other and third and fourth sides opposed to each other, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion constitutes the first side, the second protrusion constitutes the second side, the third protrusion constitutes the third side, the fourth protrusion constitutes the fourth side, the first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion; battery.

3. 10. The battery of claim 1, The opening has a rectangular shape, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion constitutes one short side of the rectangle, the second protrusion constitutes the other short side of the rectangle; the third protrusion constitutes one long side of the rectangle, the fourth protrusion constitutes the other long side of the rectangle; the first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion; battery.

4. 4. The battery of claim 3, The stacking direction of the electrode stack is along the short side, The width direction of the electrode stack is along the long side. battery.

5. 10. The battery of claim 1, The protrusion protrudes from the outer edge of the base. battery.

6. 10. The battery of claim 1, The planar shape of the base is rectangular, the rectangle has first and second sides opposed to each other and third and fourth sides opposed to each other, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protruding portion protrudes from the first side, the second protruding portion protrudes from the second side, the third protruding portion protrudes from the third side, the fourth protruding portion protrudes from the fourth side, the first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion; battery.

7. 10. The battery of claim 1, The planar shape of the base is rectangular, the protrusions include a first protrusion, a second protrusion, a third protrusion, and a fourth protrusion, the first protrusion protrudes from one short side of the rectangle, the second protrusion protrudes from the other short side of the rectangle, the third protrusion protrudes from one long side of the rectangle, the fourth protrusion protrudes from the other long side of the rectangle, the first protruding portion and the second protruding portion are thicker than the third protruding portion and the fourth protruding portion; battery.

8. 8. The battery of claim 7, The stacking direction of the electrode stack is along the short side, The width direction of the electrode stack is along the long side. battery.

9. The battery according to any one of claims 1 to 8, The ratio of the width of the current collecting portion to the width of the opening is 0.9 or more. battery.

10. The battery according to any one of claims 1 to 8, The thickness of the base portion is smaller than the protrusion length of the protrusion portion. battery.

11. The battery according to any one of claims 1 to 8, The thickness of the terminal is smaller than the thickness of the electrode stack. battery.

12. The battery according to any one of claims 1 to 8, the base has a first surface and a second surface; the first surface faces the electrode stack, the second surface faces the opposite side to the first surface, The current collecting portion is joined to the first surface of the base. battery.

13. 13. The battery of claim 12, a bus bar connected to the second surface of the base; battery.

14. 13. The battery of claim 12, A portion of the current collecting portion is ultrasonically bonded or laser bonded to the first surface of the base. battery.

15. The battery according to any one of claims 1 to 8, The protrusion has an insulating layer on an end surface facing the electrode stack. battery.

16. The battery according to any one of claims 1 to 8, the protrusion has an outer surface and an inner surface; the electrode stack and the current collecting portion are housed in a laminate exterior body, The laminate exterior is adhered to the outer surface of the protrusion. battery.

17. A battery pack comprising a plurality of batteries and at least one bus bar; the bus bar electrically connects one of the batteries to another of the batteries; one or both of the one battery and the other battery has an electrode stack, a current collector, and a terminal; the electrode stack is electrically connected to the terminal via the current collecting portion, the terminal has a base, a protrusion, and an opening; The base portion is a first surface facing the electrode stack; a second surface facing the opposite side to the first surface and to which the bus bar is connected; and the protruding portion protrudes from the first surface of the base portion toward the electrode stack, the shape of the opening is defined by the protrusion; The current collecting portion is inserted into the opening and connected to the terminal. Battery pack.

18. The battery pack according to claim 17, The bus bar has a slit. Battery pack.

Images