Secondary batteries

Abstract

To provide a technology that can maintain the shape of the frame member covering the electrode stack while allowing the secondary battery to expand and contract. [Solution] The secondary battery comprises an electrode stack 2, a frame member 3 covering at least four surfaces of the electrode stack 2, and a support member 4 having a higher modulus of elasticity than the frame member and positioned in contact with the frame member to support the frame member. The support member 4 extends from a position corresponding to the lower surface of the electrode stack 2 in the stacking direction to a position corresponding to the upper surface. The support member 4 is continuous across at least four surfaces.

Description

Technical Field

[0001] The present invention relates to a secondary battery.

Background Art

[0002] A secondary battery is a battery that can repeat charge and discharge. As a secondary battery, a battery including an electrolyte layer containing a solid electrolyte is known. Such a secondary battery has a configuration in which an electrolyte layer and an electrode layer are laminated (hereinafter referred to as an electrode laminate). In such a secondary battery, for various reasons, a frame-shaped member (hereinafter sometimes referred to as a frame member) may be provided so as to cover the electrode laminate.

[0003] For example, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2020-4528) describes providing a first resin layer and a second resin layer on the side surface of a battery laminate in an all-solid-state battery.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, as a secondary battery containing a solid electrolyte, there is a deposition type secondary battery. A deposition type secondary battery is a secondary battery configured such that a lithium-containing substance is deposited on a negative electrode during charging. In a deposition type secondary battery, the electrode laminate greatly expands and contracts with charge and discharge. In such a secondary battery, when a frame member is disposed so as to cover the electrode laminate, the frame member needs to have flexibility to such an extent that the expansion and contraction of the electrode laminate are allowed.

[0006] However, secondary batteries can be subjected to shocks and vibrations. For example, when a secondary battery is used in a car, it is subjected to shocks during driving. If a highly flexible material is used as the frame component, the frame component may not be able to maintain its shape when subjected to shocks. As a result, the secondary battery may be damaged.

[0007] Therefore, an object of the present invention is to provide a technology that can maintain the shape of the frame member covering the electrode stack while allowing the secondary battery to expand and contract. [Means for solving the problem]

[0008] In one embodiment, the secondary battery according to the present invention comprises: an electrode stack in the shape of a rectangular parallelepiped, including a deposition-type battery element, the battery element having an electrolyte layer and an electrode layer stacked along the stacking direction, the electrolyte layer containing a solid electrolyte; a frame member covering at least four surfaces of the electrode stack, the four surfaces consisting of two sets of opposing surfaces; and a support member having a higher modulus of elasticity than the frame member and positioned in contact with the frame member to support the frame member. The support member extends from a position corresponding to the lower surface of the electrode stack in the stacking direction to a position corresponding to the upper surface. The support member is continuous across at least four surfaces. [Effects of the Invention]

[0009] According to the present invention, a technology is provided that can maintain the shape of the frame member covering the electrode stack while allowing the secondary battery to expand and contract. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a schematic perspective view showing a secondary battery according to the first embodiment. [Figure 2] Figure 2 is a schematic diagram showing a secondary battery according to Modification 1. [Figure 3] Figure 3 shows the side view of the secondary battery along the Y direction. [Figure 4]Figure 4 is a schematic diagram showing a modified example 2. [Figure 5] Figure 5 is a schematic diagram showing modified example 3. [Figure 6] Figure 6 is a schematic diagram showing a secondary battery according to Modification 4. [Figure 7] Figure 7 is a schematic diagram showing modified example 5. [Figure 8] Figure 8 is a schematic diagram showing modified example 6. [Figure 9] Figure 9 is a schematic diagram showing modified example 7. [Figure 10] Figure 10 is a schematic diagram showing modified example 8. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below with reference to the drawings.

[0012] (Secondary battery) Figure 1 is a schematic perspective view of a secondary battery 1 according to the first embodiment. This secondary battery 1 has an electrode stack 2, a frame member 3, and a support member 4. Although not shown, these are housed in an outer casing. The outer casing is, for example, a metal laminate material. In other words, the secondary battery 1 according to this embodiment is provided as a so-called laminate cell.

[0013] (Electrode stack) The electrode stack 2 is shaped like a rectangular parallelepiped. In Figure 1, the X, Y, and Z directions are defined, corresponding to the directions in which each side of the electrode stack 2 extends.

[0014] Although not shown in the diagram, the electrode stack 2 includes a deposition-type battery element.

[0015] "Deposition type" means, as described above, having a structure in which a lithium-containing substance is deposited on the negative electrode during charging. Examples of the lithium-containing substance to be deposited include metallic lithium and a metal alloyed with lithium (lithium alloy). For example, it may contain metallic lithium in which at least a part of the negative electrode active material is deposited, and may contain a compound alloyed with lithium, carbon, or the like as an active material other than metallic lithium. Although detailed illustration is omitted, the battery element has electrolyte layers and electrode layers stacked along the stacking direction. In the present embodiment, it is assumed that the stacking direction is the Z direction. The electrolyte layer contains a solid electrolyte. The electrolyte layer is sandwiched between a pair of electrode layers (a positive electrode active material layer and a negative electrode active material layer). Further, in the electrode laminate 2, negative electrode current collector foils and positive electrode current collector foils are arranged so as to sandwich the battery element. During charging, lithium contained in the positive electrode active material layer moves to the negative electrode side through the electrolyte layer as lithium ions, and is deposited as metallic lithium or a lithium alloy or the like between the electrolyte layer and the negative electrode current collector foil. The deposited lithium-containing substance or the like functions as a negative electrode active material layer. On the other hand, during discharging, lithium contained in the negative electrode active material layer moves to the positive electrode active material layer side through the electrolyte layer and is occluded in the positive electrode active material layer. Preferably, the battery element in the present embodiment is of the "full deposition type". The full deposition type battery element is a battery element configured such that substantially all of the metallic lithium as the negative electrode active material moves to the positive electrode side during complete discharge.

[0016] The electrode laminate 2 including the deposition type battery element repeats the deposition and disappearance of the lithium-containing substance on the negative electrode side with charge and discharge. Therefore, the electrode laminate 2 greatly expands and contracts with charge and discharge, particularly in the stacking direction.

[0017] (Frame member) The frame member 3 is provided so as to cover at least four surfaces of the electrode laminate 2. The "four surfaces" here consist of two pairs of opposing surfaces. That is, the frame member 3 is arranged so as to cover four surfaces that are linearly continuous when expanded. In the present embodiment, the frame member 3 is arranged so as to cover the upper and lower surfaces in the stacking direction and a pair of opposing side surfaces.

[0018] There are various reasons for providing the frame member 3. For example, by providing the frame member 3, the electrode laminate 2 can be protected from impacts and the like. Alternatively, by using an insulator as the frame member 3, a short circuit on the side surface of the electrode laminate 2 can be prevented. Alternatively, the electrolyte layer and the electrode layer included in the electrode laminate 2 may have somewhat different areas. As a result, irregularities may be formed on the side surface of the electrode laminate 2. In such a case, by arranging the frame member 3, the irregularities on the side surface of the electrode laminate 2 can be absorbed, and the outer shape can be made flat.

[0019] As described above, current collecting foils (a positive electrode current collecting foil and a negative electrode current collecting foil) are connected to the battery element. Although not shown, each current collecting foil protrudes laterally from the side surface of the electrode laminate 2. When the surface from which the current collecting foil protrudes is covered by the frame member 3, the current collecting foil extends so as to penetrate the frame member 3. That is, although not shown, the frame member 3 may be provided with an opening for passing the current collecting foil.

[0020] As described above, the electrode laminate 2 expands and contracts greatly with charge and discharge. Therefore, the frame member 3 has a certain degree of flexibility so that the expansion and contraction of the electrode laminate 2 are allowed. The elastic modulus of the frame member 3 is, for example, 100 MPa or less. The frame member 3 is formed of, for example, a resin material.

[0021] (Support member) As described above, the frame member 3 has a certain degree of flexibility. Therefore, when vibrations, impacts, or the like are applied, the frame member 3 may deform. For example, the secondary battery 1 according to the present embodiment is used for an automobile. In this case, vibrations and impacts during running may be applied to the secondary battery 1. If the frame member 3 is deformed by an impact or the like, an impact or the like may also be applied to the electrode laminate 2, and the secondary battery 1 may be damaged.

[0022] Therefore, in this embodiment, a support member 4 is provided. That is, the support member 4 is provided to maintain the shape of the frame member 3. In other words, the support member 4 functions as a "beam" relative to the frame member 3. The support member 4 is positioned in contact with the frame member 3 so as to support the frame member 3. The support member 4 has a higher modulus of elasticity than the frame member 3. For example, the modulus of elasticity of the support member is greater than 100 MPa. There is no particular upper limit to the modulus of elasticity of the support member 4. For example, the modulus of elasticity of the support member 4 is 1000 MPa or less. The support member 4 is formed of, for example, a resin material.

[0023] The support member 4 is provided on the portion of the frame member 3 that covers the aforementioned "four surfaces". Furthermore, the support member 4 is continuous across the "four surfaces".

[0024] The support member 4 extends from a position corresponding to the lower surface of the electrode stack 2 to a position corresponding to the upper surface in the stacking direction (Z direction in this embodiment).

[0025] The presence of the support member 4 having the above-described configuration prevents deformation of the frame member 3, even when a highly flexible material is used as the frame member 3. In other words, it is possible to maintain the shape of the frame member 3 covering the electrode stack 2 while allowing the secondary battery to expand and contract.

[0026] Note that in Figure 1, the support member 4 is depicted as being positioned on the surface of the frame member 3. However, as shown in Figure 1, the support member 4 may be positioned on the surface of the frame member 3.

[0027] On the other hand, part or all of the support member 4 may be embedded in the frame member 3. The configuration in which at least a part of the support member 4 is embedded in the frame member 3 is easy to mold. For example, when manufacturing the secondary battery 1, first the frame member 3 is molded from a resin material. The frame member 3 is molded to have a channel for the support member 4. Next, a resin material for forming the support member 4 is injected into the channel. After injection, the injected resin material is hardened. This results in a configuration in which the support member 4 is embedded in the frame member 3.

[0028] When the support member 4 is embedded in the frame member 3, it is preferable that the support member 4 has a single linear structure without branches. That is, it is preferable that the support member 4 has a structure that can be drawn in a single continuous line. In this specification, such a linear structure without branches will be referred to as a "non-branched linear structure" below.

[0029] When a non-branched linear structure is adopted as the support member 4, molding becomes easier. Specifically, when a non-branched linear structure is adopted, there are no parts in the flow path for forming the support member 4 where the resin material branches or merges. If branching or merging parts exist, it may be difficult to uniformly fill the resin material. In contrast, when a non-branched linear structure is adopted, there are no such branching and merging parts, so the resin material can be uniformly filled throughout the entire flow path. Therefore, the occurrence of structural defects in the support member 4 and the frame member 3 can be suppressed.

[0030] More preferably, the non-branched linear structure is linear in each face.

[0031] In this embodiment, the case in which the frame member 3 is arranged to cover four surfaces of the electrode stack 2 has been described. However, the frame member 3 only needs to cover "at least four surfaces" of the electrode stack 2. For example, the frame member 3 may be provided to cover all six surfaces of the electrode stack 2. Similarly, the support member 4 only needs to be provided corresponding to "at least four surfaces". For example, the support member 4 may be provided corresponding to all six surfaces. If the support member 4 is provided corresponding to all six surfaces, deformation of the frame member 3 can be prevented more reliably.

[0032] Furthermore, in this embodiment, as shown in Figure 1, the case in which the top and bottom surfaces and a pair of sides in the stacking direction are covered by the frame member 3 has been described. However, the "four surfaces" of the "at least four surfaces" covered by the frame member 3 do not necessarily have to be the top and bottom surfaces and a pair of sides in the stacking direction. For example, the frame member 3 may cover the four sides but not the top and bottom surfaces in the stacking direction.

[0033] Next, we will describe some modifications of this embodiment. (Variation 1) First, let's describe the first modification. Figure 2 is a schematic diagram showing the secondary battery 1 according to the first modification. Figure 3 is a view of this secondary battery 1 along the Y direction, and is a schematic diagram showing the positional relationship between the frame member 3 and the support members 4 (4-A and 4-B) in the portion covering the upper surface in the stacking direction.

[0034] As shown in Figure 2, the support member 4 has two non-linear branched structures (4-A and 4-B). In Figure 2, for clarity, the support members 4 (4-A and 4-B) are depicted as being located on the surface of the frame member 3. However, in reality, the support members 4 (4-A and 4-B) are embedded in the frame member 3.

[0035] The two nonlinear branch structures (4-A and 4-B) extend along the diagonals of each face. Therefore, when viewed from the front, the two nonlinear branch structures intersect. However, as shown in Figure 3, the two nonlinear branch structures (4-A and 4-B) are embedded in the frame member 3 at different depths so that they do not come into contact with each other.

[0036] Even when adopting a configuration like this modified example, the support member 4 prevents deformation of the frame member 3. Furthermore, because the support member 4 has a non-linear branching structure, it is possible to suppress poor filling of the resin material during molding.

[0037] In other words, as shown in this modified example, the number of nonlinear branching structures included in the support member 4 is not limited to one, but may be multiple.

[0038] (Modification 2) Next, we will describe Modification 2. Figure 4 is a schematic diagram showing Modification 2. Figure 4 shows the shape of the support member 4. In the first embodiment (see Figure 1, etc.), we described the case where the support member 4 extends along the diagonal of the surface. However, the support member 4 does not necessarily have to extend along the diagonal. In the modification shown in Figure 4, the support member 4 is arranged in a fence-like manner. That is, the support member 4 has a portion that extends along the outer periphery (i.e., edge) of the surface and a portion that extends across the surface.

[0039] As shown in this modified example, the support member 4 does not necessarily have to extend along the diagonal. Even with a configuration like this modified example, the support member 4 can reinforce the frame member 3, and deformation of the frame member 3 can be suppressed.

[0040] (Variation 3) Next, we will describe Modification 3. Figure 5 is a schematic diagram showing Modification 3. Figure 5 shows the configuration of the support member 4. In this modification, the support member 4 is plate-shaped. Even when such a configuration is adopted, the frame member 3 can be reinforced by the support member 4, and deformation of the frame member 3 can be suppressed. In other words, the support member 4 does not necessarily have to have a linear structure.

[0041] However, if all surfaces of the electrode stack 2 are covered by the frame member 3, and the support member 4 is provided so as to completely cover all surfaces, expansion and contraction of the electrode stack 2 becomes difficult to tolerate. Also, the secondary battery 1 becomes heavier. Therefore, from the viewpoint of allowing expansion and contraction and from the viewpoint of weight, it is preferable that at least a portion of the support member 4 has a linear structure.

[0042] (Modification 4) Next, we will describe Modification 4. Figure 6 is a schematic diagram showing the secondary battery 1 according to Modification 4. Figure 6 shows the frame member 3 and the support member 4. Note that the electrode stack 2 is not shown.

[0043] In this modified example, the support member 4 has a linear structure. The linear structure extends along the diagonal on each face. Similar to the first embodiment, the linear structure is continuous across four faces. Here, the linear structure has a corner 4-C provided between two adjacent faces. The corner 4-C is thicker than the rest of the linear structure.

[0044] According to this modified version, damage to the secondary battery 1 is more reliably prevented. When the secondary battery 1 is subjected to impact or other forces, stress tends to concentrate at the corners (the connection points between edges). Therefore, the support member 4 is usually prone to damage at the corners. In contrast, according to this modified version, the thickness of corner 4-C is greater than that of other parts, thus preventing damage to the corners. Impact and vibration resistance can be maintained over a long period of time.

[0045] (Variation 5) Next, we will describe Modification 5. Figure 7 is a schematic diagram showing Modification 5. Figure 7 shows the configuration of the frame member 3 in the portion covering one surface of the electrode stack 2 in a perspective view.

[0046] In this modified example, the support member 4 has an embedded portion 4-1 and an exposed portion 4-2. The embedded portion 4-1 is the part embedded in the frame member 3. The exposed portion 4-2 is the part that protrudes outward from the frame member 3.

[0047] The exposed portion 4-2 is exposed to the outside of the frame member 3 in at least two of the X-axis, Y-axis, and Z-axis directions. That is, the support member 4 protrudes outward from the frame member 3 in at least two of the X-axis, Y-axis, and Z-axis directions. In the example shown in Figure 7, the support member 4 protrudes outward from the frame member 3 as the exposed portion 4-2 in the Z-axis and Y-axis directions.

[0048] According to this modified configuration, wear of the frame member 3 due to friction with the exterior material is suppressed. As previously described, the secondary battery 1 is provided with an exterior material (not shown). The electrode stack 2, frame member 3, and support member 4 are housed in this exterior material. For example, a metal laminate film can be used as the exterior material.

[0049] In this case, if the highly flexible frame member 3 comes into contact with the exterior material, the frame member 3 may wear down due to friction with the exterior material. In contrast, in this modified example, since the support member 4 protrudes outside the frame member 3 in at least two axial directions, the exterior material preferentially contacts the support member 4 rather than the frame member 3. Since the support member 4 is hard (has a high modulus of elasticity), it is less likely to wear down even if it comes into contact with the exterior material. This suppresses wear on the frame member 3 and improves the durability of the secondary battery 1.

[0050] (Experimental variation 6) Next, we will describe Modification 6. Figure 8 is a schematic diagram showing Modification 6. Figure 8 shows the configuration of the frame member 3 in the portion covering one surface of the electrode stack 2 as a perspective view.

[0051] In this modified example, the support member 4 has a linear structure. Furthermore, the support member 4 is embedded in the frame member 3. Here, the support member 4 extends along a direction non-parallel to any of the XY, YZ, and ZX planes. In other words, the coordinates on the XY plane are different at one end (see end A in Figure 8) and the other end (see end B in Figure 8) of the support member 4 in the Z direction. That is, the support member 4 extends in three dimensions.

[0052] According to this modified example, the support member 4 has a three-dimensional structure. Therefore, deformation of the frame member 3 can be prevented regardless of the direction in which force such as impact is applied. Impact vibration resistance is further improved.

[0053] (Example 7) Next, we will explain Modification 7. Figure 9 is a schematic diagram illustrating Modification 7.

[0054] In this modified example, the frame member 3 covers at least the upper and lower surfaces of the electrode stack 2 in the stacking direction (Z direction in Figure 9). The support member 4 has a pair of plate-like portions 4-3, each of which is plate-shaped. The pair of plate-like portions 4-3 are provided at positions corresponding to the upper and lower surfaces of the electrode stack 2 in the stacking direction.

[0055] The support member 4 further has a connecting portion 4-4 in addition to the pair of plate-like portions 4-3. The connecting portion 4-4 is provided at a position corresponding to the side surface of the electrode laminate 2 and connects the pair of plate-like portions 4-3 to each other. As a result, the support member 4 is continuous across at least four surfaces.

[0056] Even with a configuration like the one shown in this modified example, deformation of the frame member 3 can be prevented.

[0057] Furthermore, in a typical secondary battery 1 using a solid electrolyte, the electrode stack 2 is pressurized along the stacking direction to achieve good charge and discharge characteristics. Therefore, the frame member 3 is prone to deformation as it is compressed in the stacking direction. In contrast, according to this modified example, since plate-shaped support members 4 are arranged on the upper and lower surfaces in the stacking direction, the shape of the frame member 3 is maintained even when the secondary battery 1 is pressurized along the stacking direction.

[0058] (Variation 8) Next, we will describe Modification 8. Figure 10 is a schematic diagram showing Modification 8. Figure 10 shows the frame member 3 and the support member 4. Note that the electrode laminate 2 is not shown.

[0059] In this modified example, the support member 4 has a portion that extends along the edge of the electrode stack 2. In the example shown in Figure 10, the support member 4 is positioned along all edges of the electrode stack 2. In this specification, "edge" is understood to be part of a "plane". Therefore, even in the configuration shown in Figure 10, the support member 4 can be said to be "continuous across at least four planes" of the electrode stack 2.

[0060] The parts of the electrode stack 2 corresponding to the edges, i.e., the corners, are susceptible to stress from impacts, etc. According to this modified example, since the support member 4 is provided in the parts where such stress is likely to occur, the shape of the frame member 3 is more easily maintained.

[0061] The present invention has been described above with reference to embodiments and their modifications. The embodiments and modifications described herein can be combined and used in a manner consistent with the invention.

[0062] The following is a summary of typical configurations included in the present invention and their effects.

[0063] [Note] (Note 1) A secondary battery comprising: an electrode stack 2 in the shape of a rectangular parallelepiped, which includes a deposition-type battery element, the battery element having an electrolyte layer and an electrode layer stacked along the stacking direction, the electrolyte layer containing a solid electrolyte; a frame member 3 covering at least four surfaces of the electrode stack 2, the four surfaces consisting of two sets of opposing surfaces; and a support member 4 having a higher modulus of elasticity than the frame member 3 and positioned in contact with the frame member 3 to support the frame member 3, the support member 4 extending from a position corresponding to the lower surface to a position corresponding to the upper surface of the electrode stack 2 in the stacking direction, and the support member 4 being continuous across at least four surfaces.

[0064] In this configuration, the flexible frame member 3 is supported by the support member 4. Therefore, while allowing the expansion and contraction of the electrode laminate 2, deformation of the frame member 3 in the event of impact or other forces is prevented.

[0065] (Note 2) A secondary battery as described in Appendix 1, wherein at least a portion of the support member 4 is embedded in the frame member 3.

[0066] This configuration makes it easier to mold the frame member 3 and the support member 4 during manufacturing.

[0067] (Note 3) A secondary battery as described in Appendix 2, wherein the X, Y, and Z axes are defined along the direction in which each side of the electrode stack 2 extends, and the secondary battery 1 further has an outer material that houses the electrode stack, a frame member, and a support member, and the support member protrudes outward from the frame member 3 in at least two of the X-axis, Y-axis, and Z-axis directions.

[0068] With this configuration, the exterior material preferentially contacts the support member 4 rather than the frame member 3. Therefore, wear of the frame member 3 due to friction between the frame member 3 and the exterior material is suppressed.

[0069] (Note 4) A secondary battery as described in Appendix 2 or 3, wherein the X, Y, and Z axes are defined along the direction in which each side of the electrode stack 2 extends, and the support member 4 has a linear structure embedded in the frame member 3, the linear structure extending along a direction nonparallel to any of the XY, YZ, and ZX planes.

[0070] With this configuration, the support member 4 extends in three dimensions, which prevents deformation of the frame member 3 regardless of the direction in which impacts or other forces are applied.

[0071] (Note 5) A secondary battery as described in any of Appendix 1 to 4, wherein the support member 4 has at least one non-branched linear structure.

[0072] This configuration makes it easier to mold the frame member 3 and the support member 4 during manufacturing.

[0073] (Note 6) A secondary battery as described in Appendix 5, wherein the support member 4 consists of only one non-branched linear structure.

[0074] This configuration makes it easier to mold the frame member 3 and the support member 4 during manufacturing.

[0075] (Note 7) A secondary battery as described in any of the appendices 1 to 7, wherein the frame member 3 covers all six sides of the electrode stack 2, and the support member 4 is continuously provided across all six sides.

[0076] This configuration makes it possible to more reliably prevent deformation of the frame member 3.

[0077] (Note 8) A secondary battery as described in any of Appendix 1 to 7, wherein the support member 4 has a linear structure, and the linear structure has corners formed between two adjacent surfaces on at least four surfaces, and the corners are thicker than the other parts of the linear structure.

[0078] With this configuration, the strength of the support member 4 is increased at the corners where stress tends to concentrate, thus more reliably preventing damage to the support member 4.

[0079] (Note 9) A secondary battery as described in any of the appendices 1 to 8, wherein the frame member 3 is arranged to cover at least four surfaces, including the upper and lower surfaces of the electrode stack 2 in the stacking direction, and the support member 4 has a pair of plate-like portions, each of which is plate-shaped, and the pair of plate-like portions are provided on the upper and lower surfaces of the electrode stack 2.

[0080] With this configuration, deformation of the frame member 3 is more reliably prevented.

[0081] (Note 10) A secondary battery as described in any of the appendices 1 to 9, wherein the support member 4 has a portion that extends along the edge of the electrode stack 2.

[0082] With this configuration, the support members 4 are provided along the edges where stress tends to concentrate, thus more reliably preventing deformation of the frame members 3. [Explanation of symbols]

[0083] 1...Secondary battery, 2...Electrode stack, 3...Frame member, 4...Support member, 4-1...Buried part, 4-2...Exposed part, 4-3...Non-branched linear structure, 4-4...Non-branched linear structure, 4-5...Plane part, 4-6...Support member corner part, 4-7...Plate-shaped part, 4-8...Edge part, 5...Battery element

Claims

1. An electrode stack in the shape of a rectangular parallelepiped, comprising a deposition-type battery element, wherein the battery element has an electrolyte layer and an electrode layer stacked along the stacking direction, and the electrolyte layer contains a solid electrolyte, and A frame member covering at least four surfaces of the electrode stack, wherein the four surfaces consist of two sets of opposing surfaces, A support member having a higher modulus of elasticity than the frame member and positioned in contact with the frame member to support the frame member, Equipped with, The support member extends from a position corresponding to the lower surface of the electrode stack in the stacking direction to a position corresponding to the upper surface. The support member is continuous across at least four surfaces. Secondary battery.

2. A secondary battery according to claim 1, At least a portion of the support member is embedded in the frame member. Secondary battery.

3. A secondary battery according to claim 2, The X, Y, and Z axes are defined along the direction in which each side of the electrode stack extends. The secondary battery further comprises an outer casing material that houses the electrode stack, the frame member, and the support member. The support member extends outward from the frame member in at least two of the following directions: the X-axis direction, the Y-axis direction, and the Z-axis direction. Secondary battery.

4. A secondary battery according to claim 2, The X, Y, and Z axes are defined along the direction in which each side of the electrode stack extends. The support member has a linear structure embedded in the frame member. The linear structure extends along directions that are not parallel to any of the XY, YZ, and ZX planes. Secondary battery.

5. A secondary battery according to claim 1 or 2, The support member has at least one non-branched linear structure. Secondary battery.

6. A secondary battery according to claim 5, The support member consists of only one of the non-branched linear structures. Secondary battery.

7. A secondary battery according to claim 1 or 2, The frame member covers all six sides of the electrode stack, The support member is provided continuously across all six surfaces. Secondary battery.

8. A secondary battery according to claim 1 or 2, The support member has a linear structure, The linear structure has corners formed between two adjacent surfaces in the at least four surfaces, The aforementioned corner is thicker than the other parts of the linear structure. Secondary battery.

9. A secondary battery according to claim 1 or 2, The frame member is arranged to cover at least four surfaces, including the upper and lower surfaces of the electrode stack in the stacking direction. The support member has a pair of plate-like portions, each of which is plate-shaped. The pair of plate-like portions are provided on the upper and lower surfaces of the electrode stack. Secondary battery.

10. A secondary battery according to claim 1 or 2, The support member has a portion that extends along the edge of the electrode stack. Secondary battery.

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