All-solid-state batteries
The all-solid-state battery design addresses the issue of current collector foil damage by using a slitted current collector foil terminal that flexibly adapts to the laminate's expansion and contraction, ensuring a stable connection and improved durability.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- NISSAN MOTOR CO LTD
- Filing Date
- 2024-11-28
- Publication Date
- 2026-06-09
AI Technical Summary
Existing all-solid-state batteries face issues with the current collector foils being cut due to expansion and contraction during charge and discharge cycles.
The design incorporates a current collector foil terminal with a flat plate portion featuring slits and mounting portions, allowing the foil to flexibly accommodate the laminate's expansion and contraction by dividing it into groups that pass through these slits, maintaining a constant distance and minimizing stress.
The solution enables the current collector foil to follow the laminate's expansion and contraction, reducing the risk of damage and maintaining a consistent connection, thereby enhancing the battery's durability and performance.
Smart Images
Figure 2026093794000001_ABST
Abstract
Description
Technical Field
[0001] This technology relates to all-solid-state batteries.
Background Art
[0002] The secondary battery described in Patent Document 1 includes a power generation element and an exterior portion that houses the power generation element inside. The exterior portion has a cylindrical portion having openings on two opposing surfaces, lid terminals disposed at each of the openings, and a resin disposed between the cylindrical portion and the lid terminals. The cylindrical portion and the lid terminals are integrated with the resin, and the current collector of the power generation element and the lid terminals are electrically connected.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] The battery described in Patent Document 1 describes inserting and fixing the current collector into an opening provided in the slit portion of the lid terminal. However, due to the expansion and contraction of the battery during charge and discharge, the foil of the current collector may be cut.
[0005] This technology has been made in view of such circumstances, and an object thereof is to provide an all-solid-state battery that can follow the expansion and contraction of a laminate.
Means for Solving the Problems
[0006] A solid-state battery according to one aspect of this technology comprises a laminate in which a negative electrode, a solid electrolyte layer, and a positive electrode are repeatedly stacked in one direction; a current collector foil provided on each of the negative electrodes and drawn out from the laminate in a direction perpendicular to the one direction; a current collector foil provided on each of the positive electrodes and drawn out from the laminate in a direction perpendicular to the one direction; and a current collector foil terminal provided on the current collector foil of the negative electrode and the current collector foil of the positive electrode, respectively, wherein the current collector foil terminal has a flat plate portion having an inner surface and an outer surface located on opposite sides to each other, the inner surface facing the laminate, and the flat plate portion extending from the inner surface to the outer surface The gist of the invention is that the flat plate portion has multiple slits that penetrate along the thickness direction, with the direction perpendicular to the thickness direction and the direction perpendicular to the one direction being the longitudinal direction, the direction parallel to the one direction being the width direction, and the slits arranged along the one direction, and multiple mounting portions partitioned by the slits, and in each of the negative electrode and the positive electrode, the current collector foil has a portion that passes from the inner surface through the slits and faces the outer surface of the mounting portion, and the facing portion has a joint portion located on the tip side and joined to the mounting portion, and a non-joint portion located closer to the laminate than the joint portion and not joined to the outer surface. [Effects of the Invention]
[0007] According to one aspect of this technology, an all-solid-state battery is provided that can follow the expansion and contraction of a laminate. [Brief explanation of the drawing]
[0008] [Figure 1] This is a plan view showing an example of the configuration of an all-solid-state battery according to Embodiment 1. [Figure 2] Figure 1 is a front view showing an example of the configuration of an all-solid-state battery as viewed from the front. [Figure 3] This is a longitudinal cross-sectional view showing an example of the cross-sectional configuration of the laminate according to Embodiment 1. [Figure 4] This is a perspective view showing an example of a current collector foil terminal according to Embodiment 1. [Figure 5] This is a cross-sectional view showing an example of the cross-sectional configuration of an all-solid-state battery as seen from the AA direction in Figure 2. [Figure 6] This is a longitudinal cross-sectional view showing the cross-sectional configuration of the current collector foil and current collector foil terminal when the SOC is 0%. [Figure 7] This is a longitudinal cross-sectional view showing the cross-sectional configuration of the current collector foil and current collector foil terminal when the SOC is 50%. [Figure 8] This is a longitudinal cross-sectional view showing the cross-sectional configuration of the current collector foil and current collector foil terminal when the SOC is 100%. [Figure 9] This is a partially cut, enlarged perspective view showing an example of the configuration of the outer surface of the current collector foil and current collector foil terminal according to Embodiment 1. [Figure 10] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 1 of Embodiment 1. [Figure 11] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 1 of Embodiment 1. [Figure 12] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 1 of Embodiment 1. [Figure 13] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 1 of Embodiment 1. [Figure 14] This is a perspective view showing an example of an all-solid-state battery according to a modified example 2 of Embodiment 1. [Figure 15] Figure 14 is an exploded view of an all-solid-state battery. [Figure 16] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 3 of Embodiment 1. [Figure 17] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 3 of Embodiment 1. [Figure 18] This is a plan view showing an example of the configuration of an all-solid-state battery according to a modified example 3 of Embodiment 1. [Figure 19] Figure 18 is a front view showing an example of the configuration of an all-solid-state battery as seen from the front. [Figure 20] Figure 18 is a front view showing an example of the configuration of an all-solid-state battery as seen from the front. [Modes for carrying out the invention]
[0009] The embodiments of the present technology (the present embodiment) will be described below. In the following descriptions of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationships between the thickness and the planar dimensions, the ratios of the thicknesses of the respective devices and members, etc. are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following explanations. Also, it is a matter of course that there are portions where the dimensional relationships and ratios are different between the drawings. The definitions of directions such as up and down in the following explanations are merely for convenience of explanation and do not limit the technical idea of the present technology. For example, it is a matter of course that if the object is rotated 90° and observed, up and down are read as left and right, and if it is rotated 180° and observed, up and down are read in reverse.
[0010] [Embodiment 1] As shown in FIGS. 1 and 2, the all-solid-state battery 1 according to the present Embodiment 1 includes an exterior body 9, a laminate 10 (FIG. 2) covered and sealed by the exterior body 9, a negative electrode side external terminal 11, and a positive electrode side external terminal 12. The exterior body 9 is a rectangular exterior body and includes a rectangular cylindrical member 9a, a cap 9b fitted into one opening of the cylindrical member 9a, and a cap 9c fitted into the other opening of the cylindrical member 9a. The exterior body 9 is made of, for example, metal. Each of the negative electrode side external terminal 11 and the positive electrode side external terminal 12 is fixed to the exterior body 9, a part thereof is sealed inside the exterior body 9, and a part thereof protrudes outside the exterior body 9. The negative electrode side external terminal 11 is inserted into a hole provided at one end in the longitudinal direction of the cap 9b, and the positive electrode side external terminal 12 is inserted into a hole provided at one end in the longitudinal direction of the cap 9c. The negative electrode side external terminal 11 is located on the opposite side of the positive electrode side external terminal 12 with the exterior body 9 interposed therebetween. As the negative electrode side external terminal 11 and the positive electrode side external terminal 12, for example, metals such as aluminum (Al), Al alloy, copper (Cu), Cu alloy, nickel, or nickel alloy are used, but are not limited thereto.
[0011] As shown in FIG. 2, a current collecting foil terminal 14 is provided between the laminate 10 and the cap 9b inside the exterior body 9, and a current collecting foil terminal 15 is provided between the laminate 10 and the cap 9c. The current collecting foil terminal 14 is a terminal on the negative electrode side, and the current collecting foil terminal 15 is a terminal on the positive electrode side. The current collecting foil terminal 14 is located on the opposite side of the current collecting foil terminal 15 with the laminate 10 interposed therebetween. As the current collecting foil terminals 14 and 15, for example, metals such as aluminum (Al), Al alloy, copper (Cu), Cu alloy, nickel, nickel alloy, or stainless steel (SUS) may be used, but are not limited thereto. In the drawings according to the present embodiment, when drawing the current collecting foil terminals 14 and 15, the illustration of connection portions 14b and 15b described later may be omitted, and only the flat plate portions 14a and 15a described later may be drawn.
[0012] As shown in FIG. 2, cell internal cushioning materials 13a and 13b are provided inside the exterior body 9 so as to sandwich the laminate 10 in the vertical direction. The cell internal cushioning materials 13a and 13b expand and contract according to the expansion and contraction of the laminate 10 in the vertical direction (lamination direction described later). Also, a cell external cushioning material 13c is provided between the all-solid-state batteries 1.
[0013] The laminate 10 is an all-solid-state battery laminate. As shown in FIG. 3, the laminate 10 has a configuration in which a negative electrode 4, a solid electrolyte layer 8, and a positive electrode 7 are repeatedly arranged in one direction. The solid electrolyte layer 8 is disposed between the negative electrode 4 and the positive electrode 7. The number of laminations of the negative electrode 4, the solid electrolyte layer 8, and the positive electrode 7 is not limited in FIG. 3. The lamination direction (one direction) of the negative electrode 4, the solid electrolyte layer 8, and the positive electrode 7 is, for example, the vertical direction in FIG. 3. Also, the side surface of the laminate 10 is a surface having a normal in a direction perpendicular to the lamination direction.
[0014] The negative electrode 4 has a negative electrode layer 2 and a current collector foil 3. The current collector foil 3 of the negative electrode 4 is a negative electrode current collector foil (negative electrode current collector). The negative electrode layer 2 is provided, for example, on both sides in the thickness direction of the current collector foil 3. The negative electrode layer 2 is made of Li (lithium) metal or a Li alloy. More specifically, Li alloys include, but are not limited to, Li-Mg alloy, Li-Si alloy, Li-Al alloy, Li-Zn alloy, Li-Sn alloy, and Li-Bi alloy. When the all-solid-state battery 1 discharges, the Li contained in the negative electrode layer 2 ionizes and moves from the negative electrode 4 to the positive electrode 7 via the solid electrolyte layer 8, and is absorbed into the positive electrode layer 5. Therefore, the more the all-solid-state battery 1 discharges, the smaller the thickness of the laminate 10 in the stacking direction becomes.
[0015] The positive electrode 7 has a positive electrode layer 5 and a current collector foil 6. The current collector foil 6 of the positive electrode 7 is a positive electrode current collector foil (positive electrode current collector). The positive electrode layer 5 is provided on both sides of the current collector foil 6 in the thickness direction, for example. Examples of materials for the positive electrode layer 5 include manganese dioxide, sulfides, and fluorides, but are not limited to these. Examples of materials for the current collector foils 3 and 6 include metal foils such as aluminum (Al), Al alloys, copper (Cu), Cu alloys, nickel (Ni), nickel alloys, or stainless steel (SUS), but are not limited to these.
[0016] The solid electrolyte layer 8 of the all-solid-state battery 1 according to this embodiment is a solid, not a liquid. The solid electrolyte layer 8 only needs to function as an electrolyte layer in a secondary battery, and its material is not particularly limited. For example, the solid electrolyte layer 8 may contain a sulfide solid electrolyte. Examples of sulfide solid electrolytes include materials containing Li, phosphorus (P), sulfur (S), and halides.
[0017] As shown in Figure 3, each of the multiple negative electrodes 4 has a current collector foil 3 which is laminated within the laminate 10 and a portion which is drawn out from the side of the laminate 10 (the right side in the example shown in Figure 3). The portion which is drawn out of the current collector foil 3 is called a protrusion 31 to distinguish it from the other parts. When the protrusion 31 is not distinguished from the other parts of the current collector foil 3, it is simply called the current collector foil 3. Each of the multiple positive electrodes 7 has a current collector foil 6 which is laminated within the laminate 10 and a portion which is drawn out from the side of the laminate 10 (the left side in the example shown in Figure 3). The portion which is drawn out of the current collector foil 6 is called a protrusion 61 to distinguish it from the other parts. When the protrusion 61 is not distinguished from the other parts of the current collector foil 6, it is simply called the current collector foil 6.
[0018] The current collector foil terminal 14 shown in Figure 2 is provided with the current collector foil 3 of the negative electrode 4 shown in Figure 3, and a protrusion 31 is connected to it. The current collector foil terminal 15 shown in Figure 2 is provided with the current collector foil 6 of the positive electrode 7 shown in Figure 3, and a protrusion 61 is connected to it. The configuration of the current collector foil terminal 14 is the same as that of the current collector foil terminal 15. The configuration in which the protrusion 31 is connected to the current collector foil terminal 14 is the same as the configuration in which the protrusion 61 is connected to the current collector foil terminal 15. The wiring structure of the electrical connection from the current collector foil terminal 14 to the negative electrode side external terminal 11 is the same as the wiring structure of the electrical connection from the current collector foil terminal 15 to the positive electrode side external terminal 12. Therefore, in the following description, the protrusion 31, the current collector foil terminal 14, and the wiring structure of the electrical connection from the current collector foil terminal 14 to the negative electrode side external terminal 11 will be described, and the description of the protrusion 61, the current collector foil terminal 15, and the wiring structure of the electrical connection from the current collector foil terminal 15 to the positive electrode side external terminal 12 will be omitted.
[0019] As shown in Figures 4 and 5, the current collector foil terminal 14 has a flat plate portion 14a and a connecting portion 14b. The flat plate portion 14a has one surface and the other surface located on opposite sides. The connecting portion 14b is connected to one side of the flat plate portion 14a. The connecting portion 14b is connected, for example, to one end in the longitudinal direction of the flat plate portion 14a. The flat plate portion 14a and the connecting portion 14b are formed integrally. The connecting portion 14b is bent at an angle of about 90° with respect to the flat plate portion 14a, but the angle is not limited to 90° and it does not have to be bent. The connecting portion 14b is the part used for routing electrical wiring, and a connecting lead 16 is connected to the connecting portion 14b. As shown in Figure 5, when arranging the current collector foil terminal 14 with respect to the laminate 10, one surface is positioned to face the side surface of the laminate 10. To distinguish between one side and the other side of the flat plate portion 14a, the side facing the laminate 10 is called the inner surface 14a1, and the other side is called the outer surface 14a2. It is desirable that the inner surface 14a1 be positioned as parallel as possible to the side surface of the laminate 10. In this embodiment, the current collector foil terminal 14 is positioned such that the shorter side of the flat plate portion 14a aligns with the lamination direction (one direction) of the laminate 10.
[0020] As shown in Figure 4, the flat plate portion 14a has a plurality of slits 14c and a plurality of mounting portions 14d partitioned by the slits 14c. Each of the plurality of slits 14c penetrates the flat plate portion 14a from the inner surface 14a1 to the outer surface 14a2 along the thickness direction, the longitudinal direction is perpendicular to the thickness direction of the flat plate portion 14a and the stacking direction of the laminate 10, and the width direction is parallel to the stacking direction of the laminate 10. The plurality of slits 14c are arranged along the stacking direction of the laminate 10. The longitudinal ends of the plurality of slits 14c reach one side of the flat plate portion 14a, but do not have to. As shown in Figure 9, the end of the mounting portion 14d on the slit 14c side is rounded.
[0021] As shown in Figure 9, the multiple protrusions 31 are divided into multiple current collector foil groups 32. Each current collector foil group 32 contains multiple protrusions 31. In the example shown in Figure 9, the number of protrusions 31 in one current collector foil group 32 is 5, but this technology is not limited to this. The number of protrusions 31 in one current collector foil group 32 may be between 2 and 50, or between 5 and 10. The number of slits 14c can be determined according to the number of current collector foil groups 32, for example, the same number as the number of current collector foil groups 32. Alternatively, the number of slits 14c may be between 2 and 50.
[0022] The protruding portion 31 of the current collector foil 3 is routed from the inner surface 14a1 through the slit 14c to the outer surface 14a2 and joined to the outer surface 14a2 of the mounting portion 14d. One current collector foil group 32 passes through one slit 14c, and one current collector foil group 32 is joined to one mounting portion 14d. The width dimension of the slit 14c is made larger than the combined thickness of all the current collector foils 3 that pass through the slit 14c. Alternatively, the ends of the current collector foil groups 32 may be joined together before passing them through the slit 14c. The portion of the routed protruding portion 31 that faces the outer surface 14a2 is called the opposing portion 31a to distinguish it from the other portions. The opposing portion 31a has a joint portion 31a1 located on the tip side of the opposing portion 31a and joined to the mounting portion 14d, and a non-joint portion 31a2 located closer to the laminate 10 than the joint portion 31a1 and not joined to the outer surface 14a2. The joint portion 31a1 is joined to the mounting portion 14d using, for example, a known welding technique. Laser welding can be cited as an example of a known welding technique. As shown in Figure 6, the current collector foil group 32 located in the center in the lamination direction may be divided and joined to two mounting portions 14d adjacent to the slit 14c through which it passes.
[0023] As shown in Figure 9, a space is provided between the non-jointed portion 31a2 and the outer surface 14a2. Since the non-jointed portion 31a2 is not joined to the mounting portion 14d, it can be deformed in accordance with the expansion and contraction of the laminate 10 in the stacking direction due to charging and discharging. Figure 6 shows the cross-sectional configuration of the laminate 10, the protruding portion 31 and the flat plate portion 14a when SOC (State of Charge) = 0%, Figure 7 shows SOC = 50%, and Figure 8 shows SOC = 100%. The thickness of the laminate 10 is minimum at SOC = 0% as shown in Figure 6 and maximum at SOC = 100% as shown in Figure 8. The thickness of the laminate 10 at SOC = 50% as shown in Figure 7 is intermediate between the thickness at SOC = 0% and SOC = 100%. Then, when the SOC = 50%, the central part of the portion of the current collector foil group 32 located within the slit 14c, along one direction (the lamination direction of the laminate 10), is positioned at the center of the slit 14c in the width direction through which the current collector foil group 32 passes. In other words, the slit 14c is provided in the flat plate portion 14a so as to be in such a positional relationship. As the laminate 10 of an intermediate thickness approaches the SOC = 0% state shown in Figure 6, the portion of the current collector foil group 32 located within the slit 14c moves toward the center of the flat plate portion 14a along the lamination direction of the laminate 10, and comes into contact with the upper or lower side of the slit 14c in the width direction. Furthermore, as the laminate 10 of an intermediate thickness approaches the SOC = 100% state shown in Figure 8, the portion of the current collector foil group 32 located within the slit 14c moves toward the outer part of the flat plate portion 14a along the lamination direction of the laminate 10, and comes into contact with the lower or upper side of the slit 14c.
[0024] Furthermore, in the intermediate thickness state shown in Figure 7, the laminate 10 has a space between the non-joint portion 31a2 and the outer surface 14a2. This space increases as the SOC approaches the state of 0% shown in Figure 6, and decreases as the SOC approaches the state of 100% shown in Figure 9. In the state of 100% SOC shown in Figure 9, the non-joint portion 31a2 and the outer surface 14a2 may be in contact, and in that case, any space between them, if any, will be minimal. Note that the intermediate thickness of the laminate 10 may be the thickness of the laminate 10 when the SOC is between 45% and 55%.
[0025] As shown in Figures 6 to 8, the distance d between the laminate 10 and the flat plate portion 14a remains constant even when the charge level of the laminate 10 changes. Furthermore, the distance d can be reduced by dividing the protruding portion 31 into multiple current collector foil groups 32 and joining them to the flat plate portion 14a. For example, if the distance d when the protruding portion 31 is joined to the flat plate portion 14a as one unit is taken as 1 (d=1), then when the protruding portion 31 is divided into n parts and joined to the flat plate portion 14a, the distance d becomes 1 / n (d=1 / n). Therefore, the larger the number of divisions n, the smaller the distance d can be.
[0026] The following describes the routing of the wiring from the current collector foil 3 to the negative electrode external terminal 11. As shown in Figure 5, one end of the connecting lead 16 is connected to the connection part 14b of the current collector foil terminal 14, and the other end of the connecting lead 16 is connected to the internal terminal 17. The connecting lead 16 and the internal terminal 17 are sealed inside the outer casing 9. The portion of the negative electrode external terminal 11 that is sealed inside the outer casing 9 is connected to the internal terminal 17. The negative electrode external terminal 11 has a large diameter portion 11a and a small diameter portion 11b. The small diameter portion 11b is inserted into the hole in the cap 9b, crimped, and connected to the internal terminal 17. During discharge, electrons move from the current collector foil 3 to the negative electrode external terminal 11 via the current collector foil terminal 14, the connecting lead 16, and the internal terminal 17, following the arrows shown in Figure 5. The connecting lead 16 and the internal terminal 17 are made of a conductor such as metal. Furthermore, the all-solid-state battery 1 is provided with an insulator 18 that insulates the casing 9 from the internal terminals 17 and the negative electrode side external terminal 11. In addition, the direction in which the negative electrode side external terminal 11 protrudes from the casing 9 is parallel to the direction in which the current collector foil 3 is pulled out from the side of the laminate 10.
[0027] <Main effects of the first embodiment> The main effects of the first embodiment will be described below. The main effects of the first embodiment will be explained using the current collector foil 3 as an example, but the same effects apply to the current collector foil 6. Even if the thickness of the laminate 10 changes, the shape of the unjointed portion 31a2 that is not joined to the current collector foil terminal 14 changes flexibly in accordance with the change, making it difficult for force to be applied to the current collector foil 3. Also, even if the thickness of the laminate 10 changes, the shape of the unjointed portion 31a2 changes flexibly in accordance with the change, so the distance d between the laminate 10 and the flat plate portion 14a can be kept constant. In other words, even if the position of the current collector foil terminal 14 relative to the laminate 10 is fixed in order to keep the distance d constant, it is still difficult for force to be applied to the current collector foil 3. In this way, by providing the unjointed portion 31a2, the current collector foil 3 can follow the expansion and contraction of the laminate 10.
[0028] Furthermore, by dividing the current collector foil 3 into multiple current collector foil groups 32 and passing one current collector foil group 32 through one slit 14c, the difference in length between each current collector foil 3 within the current collector foil group 32 during charging and discharging can be minimized. In addition, by dividing the current collector foil 3 into multiple current collector foil groups 32 and joining them to the flat plate portion 14a, the distance d between the laminate 10 and the flat plate portion 14a can be reduced.
[0029] Furthermore, even if the thickness of the laminate 10 changes, the size of the space between the non-joint portion 31a2 and the outer surface 14a2 changes accordingly, allowing the shape of the non-joint portion 31a2 to change flexibly, making it difficult for force to be applied to the current collector foil 3. Also, even if the thickness of the laminate 10 changes, the size of the space between the non-joint portion 31a2 and the outer surface 14a2 changes accordingly, allowing the distance d between the laminate 10 and the flat plate portion 14a to be kept constant. In other words, even if the position of the current collector foil terminal 14 relative to the laminate 10 is fixed to keep the distance d constant, it is still difficult for force to be applied to the current collector foil 3.
[0030] Furthermore, when the thickness of the laminate 10 is at an intermediate thickness, the central part of the portion of the current collector foil group 32 located within the slit 14c is positioned at the center of the slit 14c in the width direction. This ensures that even when the thickness of the laminate 10 changes from an intermediate state towards SOC=0% or SOC=100%, a margin is secured that allows the current collector foil group 32 to move upward or downward in the width direction within the slit 14c, making it difficult for force to be applied to the current collector foil 3. In addition, the difference in length between each current collector foil 3 within the current collector foil group 32 during charging and discharging can be minimized.
[0031] Furthermore, by rounding the end of the mounting portion 14d on the slit 14c side, deformation of the current collector foil 3 can be made easier. In addition, the current collector foil 3 can be made less susceptible to damage.
[0032] Furthermore, the widthwise dimension of the slit 14c is set to be greater than the combined thickness of all the current collector foils 3 that pass through the slit 14c. By setting the widthwise dimension of the slit 14c to such a size, the current collector foils 3 can be easily passed through the slit 14c.
[0033] It is not necessary to divide the protruding portion 31 into groups of current collector foils 32. In that case, one protruding portion 31 passes through one slit 14c. Also, the number of slits 14c may be greater than the number of groups of current collector foils 32. In that case, there will be slits 14c through which the protruding portion 31 does not pass. Modifications of Embodiment 1 will be described below.
[0034] <Example 1> The arrangement positions of the negative electrode external terminal 11 and the positive electrode external terminal 12 are not limited to those shown in Figure 1. In a modification 1 of Embodiment 1, as shown in Figure 10, the negative electrode external terminal 11 and the positive electrode external terminal 12 may be positioned diagonally across the outer casing 9 in a plan view, with the outer casing 9 in between. Also, as shown in Figure 11, both the negative electrode external terminal 11 and the positive electrode external terminal 12 may protrude from the cap 9b. In that case, the current collector foils 3 and 6 are drawn out from the same side of the laminate 10, and the flat portions 14a and 15a of the current collector foil terminals 14 and 15 may be arranged side by side along the extending direction of the slit 14c. Furthermore, as shown in Figures 12 and 13, the direction in which the negative electrode external terminal 11 and the positive electrode external terminal 12 protrude from the outer casing 9 may be perpendicular to the direction in which the current collector foil 3 is drawn out from the side of the laminate 10. In Figure 12, the tips of the connecting portions 14b and 15b of the current collector foil terminals 14 and 15 are facing in opposite directions. In Figure 13, the tips of the connection points 14b and 15b of the current collector foil terminals 14 and 15 are facing each other.
[0035] <Modification 2> In a modified example of Embodiment 1, as shown in Figures 14 and 15, the outer casing 9 may be a laminated type outer casing. In that case, the parts of the connection portions 14b and 15b of the current collector foil terminals 14 and 15 that protrude to the outside of the outer casing 9 become the negative electrode external terminal 11 and the positive electrode external terminal 12. The negative electrode external terminal 11 and the positive electrode external terminal 12 are tabs. The direction in which the negative electrode external terminal 11 and the positive electrode external terminal 12 protrude from the outer casing 9 is parallel to the direction in which the current collector foils 3 and 6 are pulled out from the side surface of the laminate 10. Also, the negative electrode external terminal 11 is located on the opposite side of the positive electrode external terminal 12, with the outer casing 9 in between. As shown in Figure 15, the outer casing 9 has gusset portions 9d and 9e and plate-like members 9f and 9g. Note that the current collector foils 3 and 6 are not shown in Figure 15. The laminate 10 is covered with cell internal cushioning material 13d and housed inside the outer casing 9. The manufacturing process for the all-solid-state battery 1 having a laminated outer casing 9 includes a step of creating a vacuum inside the outer casing 9. When the inside of the outer casing 9 is evacuated, the components of the outer casing 9 are attracted to each other, and force is applied to the laminate 10. Even when force is applied to the laminate 10, the shape of the unjointed portion 31a2 that is not joined to the current collector foil terminal 14 changes flexibly, making it difficult for force to be applied to the current collector foil 3. As a result, the negative electrode side external terminal 11 and the positive electrode side external terminal 12 are prevented from being pulled into the inside of the outer casing 9, and even if they are pulled in, the amount of pull is minimal.
[0036] <Variation 3> Modification 3 of Embodiment 1 describes another form of the all-solid-state battery 1 having a laminate-type outer casing 9. The arrangement positions of the negative electrode external terminal 11 and the positive electrode external terminal 12 of the all-solid-state battery 1 are not limited to those shown in Figure 14. As shown in Figure 16, both the negative electrode external terminal 11 and the positive electrode external terminal 12 may protrude from the same side of the outer casing 9. In that case, the current collector foils 3 and 6 may be drawn out from the same side of the laminate 10, and the flat portions 14a and 15a of the current collector foil terminals 14 and 15 may be arranged side by side along the extending direction of the slit 14c. Also, as shown in Figure 17, in a plan view, the negative electrode external terminal 11 and the positive electrode external terminal 12 may be located diagonally opposite each other on the outer casing 9. Furthermore, although the connecting portions 14b, 15b and the flat plate portions 14a, 15a were adjacent along the longitudinal direction of the slits provided in the flat plate portions 14a, 15a as shown in Figures 16 and 17, they may also be adjacent along the width direction of the slits provided in the flat plate portions 14a, 15a as shown in Figures 18 and 19. Also, the positions in which the connecting portions 14b, 15b protrude from the outer casing 9 in a side view may both be on one side in the thickness direction (width direction of the slit) of the all-solid-state battery 1 as shown in Figure 19, or they may be on one side and the other side in the thickness direction (width direction of the slit) of the all-solid-state battery 1 as shown in Figure 20.
[0037] [Other embodiments] As described above, this technology is described by Embodiment 1 and its variations 1 to 3, but the discussion and drawings that constitute part of this disclosure should not be understood as limiting this technology. Various alternative embodiments and variations will become apparent to those skilled in the art from this disclosure. For example, the configurations described in Embodiment 1 and its variations 1 to 3 may be combined with each other. Also, for example, the materials listed as constituting the above-mentioned components may include additives, impurities, etc. Thus, this technology naturally includes various embodiments and the like that are not described herein. At least one of various omissions, substitutions, and modifications of the components can be made without departing from the gist of the embodiments described above. Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.
[0038] Furthermore, this technology can also employ the following configurations. (1) A laminate in which a negative electrode, a solid electrolyte layer, and a positive electrode are repeatedly stacked in one direction, A current collector foil is provided on each of the negative electrodes and is drawn out from the laminate in a direction perpendicular to the one direction, A current collector foil is provided on each of the positive electrodes and is drawn out from the laminate in a direction perpendicular to the one direction, A current collector terminal is provided for the current collector foil of the negative electrode and the current collector foil of the positive electrode, It has, The current collector foil terminal has a flat plate portion having an inner surface and an outer surface located on opposite sides, and the inner surface faces the laminate. The flat plate portion has a plurality of slits that penetrate the flat plate portion from the inner surface to the outer surface along the thickness direction, with the direction perpendicular to the thickness direction and the one direction being the longitudinal direction, the direction parallel to the one direction being the width direction, and arranged along the one direction, and a plurality of mounting portions partitioned by the slits. In each of the negative electrode and the positive electrode, the current collector foil has a portion that passes from the inner surface through the slit and faces the outer surface of the mounting portion. The opposing portion has a joint portion located on the tip side and joined to the mounting portion, and a non-joint portion located closer to the laminate than the joint portion and not joined to the outer surface. All-solid-state battery. (2) In both the negative electrode and the positive electrode, the drawn-out current collector foil is divided into a plurality of current collector foil groups. One of the current collector foil groups is passed through one of the slits. (1) The all-solid-state battery described above. (3) A space is provided between the non-jointed portion and the outer surface of the mounting portion. (1) or (2) All-solid-state battery as described above. (4) When the charge level of the laminate is 45% or more and 55% or less, the central portion of the part of the current collector foil group located within the slit along that one direction is located in the central portion of the slit in the width direction, (2) The all-solid-state battery described above. (5) The end of the mounting portion on the slit side is rounded. A solid-state battery as described in any of (1) to (4). (6) The width dimension of the slit is greater than the combined thickness of all the current collector foils passing through the slit. (2) The all-solid-state battery described above.
[0039] The scope of this technology is not limited to the illustrative and described exemplary embodiments, but also includes all embodiments that produce effects equivalent to those intended by this technology. Furthermore, the scope of this technology is not limited to the combination of features of the invention defined by the claims, but may be defined by any desired combination of specific features from all disclosed features. [Explanation of symbols]
[0040] 1...All-solid-state battery, 2...Negative electrode layer, 3...Current collector foil (negative electrode current collector foil), 4...Negative electrode, 5...Positive electrode layer, 6...Current collector foil (positive electrode current collector foil), 7...Positive electrode, 8...Solid electrolyte layer, 9...Outer casing, 9a...Cylindrical member, 9b,9c...Cap, 9d,9e...Gusset, 9f,9g...Plate-shaped member, 10...Laminate, 11...Negative electrode side external terminal, 12...Positive electrode side external terminal, 13a,13b,13d...Internal cell buffer material ,13c...Cell external buffer material, 14,15...Current collector foil terminal, 14a,15a...Flat plate section, 14a1...Inner surface, 14a2...Outer surface, 14b,15b...Connection section, 14c...Slit, 14d...Mounting section, 16...Connecting lead, 17...Internal terminal, 18...Insulator, 31,61...Protruding section, 31a...Opposite section, 31a1...Joint section, 31a2...Non-joint section, 32...Current collector foil group, d...Distance
Claims
1. A laminate in which a negative electrode, a solid electrolyte layer, and a positive electrode are repeatedly stacked in one direction, A current collector foil is provided on each of the negative electrodes and is drawn out from the laminate in a direction perpendicular to the one direction, A current collector foil is provided on each of the positive electrodes and is drawn out from the laminate in a direction perpendicular to the one direction, A current collector terminal is provided for the current collector foil of the negative electrode and the current collector foil of the positive electrode, It has, The current collector foil terminal has a flat plate portion having an inner surface and an outer surface located on opposite sides, and the inner surface faces the laminate. The flat plate portion has a plurality of slits that penetrate the flat plate portion from the inner surface to the outer surface along the thickness direction, with the direction perpendicular to the thickness direction and the one direction being the longitudinal direction, the direction parallel to the one direction being the width direction, and arranged along the one direction, and a plurality of mounting portions partitioned by the slits. In each of the negative electrode and the positive electrode, the current collector foil has a portion that passes from the inner surface through the slit and faces the outer surface of the mounting portion. The opposing portion has a joint portion located on the tip side and joined to the mounting portion, and a non-joint portion located closer to the laminate than the joint portion and not joined to the outer surface. All-solid-state battery.
2. In both the negative electrode and the positive electrode, the drawn-out current collector foil is divided into a plurality of current collector foil groups. One of the current collector foil groups is passed through one of the slits. The all-solid-state battery according to claim 1.
3. A space is provided between the non-jointed portion and the outer surface of the mounting portion. The all-solid-state battery according to claim 1 or 2.
4. When the charge level of the laminate is 45% or more and 55% or less, the central portion of the part of the current collector foil group located within the slit along that one direction is located in the central portion of the slit in the width direction, The all-solid-state battery according to claim 2.
5. The end of the mounting portion on the slit side is rounded. The all-solid-state battery according to claim 1 or 2.
6. The width dimension of the slit is greater than the combined thickness of all the current collector foils passing through the slit. The all-solid-state battery according to claim 2.