Battery

Abstract

This battery comprises: a housing having a cylindrical shape in which an opening is formed at one end part; an electrode structure disposed inside the housing; a sealing part that seals the opening of the housing; and a connection part that electrically connects the electrode structure and the sealing part. The sealing part has a first terminal part that functions as an input / output terminal of the battery, and a limiting part that limits the current between the electrode structure and the terminal part. The electrode structure has a power generation element that includes a first active material layer, a solid electrolyte layer, and a second active material layer in said order. The value obtained by dividing the capacity per unit area of the power generation element by the area of the housing is 0.03 or greater. The area of the power generation element is the area when the power generation element is cut along a plane substantially perpendicular to the lamination direction of a first active material layer, the solid electrolyte layer, and the second active material layer. The area of the housing is the area when the housing is cut along a plane substantially perpendicular to the extension direction of the cylindrical shape.

Description

battery

[0001] The present invention relates to a battery.

[0002] Patent Documents 1 to 8 disclose electricity storage devices obtained by stacking a positive electrode, a separator, and a negative electrode. (Patent Documents) (Patent Document 1) JP 2021-002495 A (Patent Document 2) JP 2021-150106 A (Patent Document 3) JP 2018-186074 A (Patent Document 4) JP 2021-197316 A (Patent Document 5) JP 2019-186107 A (Patent Document 6) JP 2019-021384 A (Patent Document 7) JP 2010-056067 A (Patent Document 8) JP 2021-064584 A General disclosure

[0003] In a first aspect of the present invention, a battery is provided. The battery includes, for example, a cylindrical casing with an opening formed at one end. The battery includes, for example, an electrode structure disposed inside the casing. The battery includes, for example, a sealing portion that seals the opening of the casing. The battery includes, for example, a connection portion that electrically connects the electrode structure and the sealing portion. In the battery, the sealing portion includes, for example, a first terminal portion that functions as an input / output terminal of the battery. The sealing portion includes, for example, a limiting portion that limits current between the electrode structure and the terminal portion when, for example, the internal pressure of the battery is greater than a predetermined first threshold value or when the output current of the battery is greater than a predetermined second threshold value. In the battery, the electrode structure includes, for example, a power generation element. The power generation element includes, for example, a first active material layer, a solid electrolyte layer, and a second active material layer, in this order.

[0004] In the above battery, the capacity per unit area of ​​the power generating element [mAh / cm ２ ] to the area of ​​the housing [cm ２ ] and the value [mAh / cm ４] is, for example, 0.03 or more. The area of ​​the power generating element is, for example, the area when the power generating element is cut along a plane approximately perpendicular to the stacking direction of the first active material layer, the solid electrolyte layer, and the second active material layer. The area of ​​the casing is, for example, the area when the casing is cut along a plane approximately perpendicular to the extension direction of the cylindrical shape.

[0005] In any of the above batteries, the area of ​​the housing is 0.20 cm ２ 78.5cm or more ２ In any of the above batteries, the housing may have a conductive cylindrical portion having a substantially cylindrical shape. In any of the above batteries, the housing may have a first insulating member disposed on an inner surface of the cylindrical portion.

[0006] In any of the above batteries, the electrode structure may have a plurality of power generating elements electrically connected in series and / or parallel. In any of the above batteries, the plurality of power generating elements may include a first power generating element and a second power generating element. In any of the above batteries, the electrode structure may have a first current collector, the first power generating element, a second current collector, and the second power generating element, in this order. In any of the above batteries, the second current collector may be disposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element. In any of the above batteries, the electrode structure may have a second insulating member covering at least a portion of the second current collector exposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element.

[0007] Any of the above batteries may include a second terminal that seals the other end of the casing and functions as an input / output terminal of the battery. In any of the above batteries, the first current collector may be electrically connected to the second terminal. In any of the above batteries, the second current collector may be electrically connected to the first terminal via the connecting portion and the limiting portion.

[0008] In any of the above batteries, the electrode structure may have a first current collector, a first power generating element, a second current collector, a second power generating element, and a third current collector, in this order. In any of the above batteries, the electrode structure may have a first wiring that electrically connects the first current collector and the third current collector. In any of the above batteries, the second insulating member may be disposed between the first wiring and the second current collector. In any of the above batteries, the first power generating element and the second power generating element may be electrically connected in parallel.

[0009] In a second aspect of the present invention, a battery is provided. The battery includes, for example, a cylindrical housing with an opening at one end. The battery includes, for example, an electrode structure disposed inside the housing. In the battery, the electrode structure includes, for example, a first current collector, a first power generating element, a second current collector, a second power generating element, and a third current collector, in this order. In the battery, each of the first power generating element and the second power generating element includes, for example, a first active material layer, a solid electrolyte layer, and a second active material layer, in this order. In the battery, the second current collector is disposed, for example, between the second active material layer of the first power generating element and the second active material layer of the second power generating element.

[0010] In the above battery, the electrode structure has, for example, a second insulating member covering at least a portion of an end of the second current collector disposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element. The electrode structure has, for example, a first wiring electrically connecting the first current collector and the third current collector. In the above battery, the second insulating member is disposed, for example, between the first wiring and the second current collector. In the above battery, the first power generating element and the second power generating element are, for example, electrically connected in parallel.

[0011] Any of the above batteries may include a conductive sealing portion that seals the opening of the housing. In any of the above batteries, the electrode structure may have a third insulating member that covers at least a portion of an end of the first current collector that contacts the first active material layer of the first power generating element and / or the second power generating element. In any of the above batteries, the electrode structure may have a second wiring that electrically connects the second current collector and the sealing portion. In any of the above batteries, the third insulating member may be disposed between the second wiring and the first current collector.

[0012] In any of the above batteries, the electrode structure may include a first cell unit, a fourth insulating member, and a second cell unit, in this order. In any of the above batteries, the first cell unit and the second cell unit may each include a first current collector, a first power generating element, a second current collector, a second power generating element, a third current collector, a third power generating element, a fourth current collector, a fourth power generating element, and a fifth current collector, in this order. In any of the above batteries, the third power generating element and the fourth power generating element may each include a first active material layer, a solid electrolyte layer, and a second active material layer, in this order. In any of the above batteries, the third current collector may be disposed between the first active material layer of the second power generating element and the first active material layer of the third power generating element. In any of the above batteries, the fourth current collector may be disposed between the second active material layer of the third power generating element and the second active material layer of the fourth power generating element. In any of the above batteries, the first battery unit and the second battery unit may be electrically connected in series. In any of the above batteries, the first power generating element, the second power generating element, the third power generating element, and the fourth power generating element included in the first battery unit may be electrically connected in parallel. In any of the above batteries, the first power generating element, the second power generating element, the third power generating element, and the fourth power generating element included in the second battery unit may be electrically connected in parallel.

[0013] In any of the above batteries, the housing may have a conductive cylindrical portion having a substantially cylindrical shape. In any of the above batteries, the housing may have a first insulating member disposed on an inner surface of the cylindrical portion.

[0014] The above summary of the invention does not list all of the necessary features of the present invention, and subcombinations of these features may also constitute inventions.

[0015] 1A and 1B are schematic diagrams showing an example of the internal structure of a cylindrical energy storage device 100; 1A and 1B are schematic diagrams showing an example of components of a sealing unit 130; 1B and 1C are schematic diagrams showing an example of the stacked structure of a battery unit 150 (stacked body); 1C and 1D are schematic diagrams showing an example of basic battery elements constituting the battery unit 150; 1D and 1E are schematic diagrams showing an example of the stacked structure of a battery unit 500 (stacked body).

[0016] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention as claimed. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0017] In this specification, when a numerical range is expressed as "A to B," the expression means A or more and B or less. Furthermore, "substituted or unsubstituted" means "substituted with any substituent, or not substituted with any substituent." The type of the above-mentioned substituent is not particularly limited unless otherwise specified in the specification. Furthermore, the number of the above-mentioned substituents is not particularly limited unless otherwise specified in the specification.

[0018] (Overview of Cylindrical Energy Storage Device 100) FIG. 1 schematically illustrates an example of the internal structure of a cylindrical energy storage device 100. In this embodiment, the cylindrical energy storage device 100 includes a housing 110, an insulating member 120, a sealing unit 130, a gasket 140, a battery unit 150, a negative electrode wiring 162, a positive electrode wiring 164, an insulating member 166, and a positive electrode lead 170. In this embodiment, the housing 110 includes a cylindrical member 112. An opening 116 is formed at one end of the cylindrical member 112, and a bottom plate 114 is disposed at the other end of the cylindrical member 112. In this embodiment, the battery unit 150 includes one or more (sometimes referred to as one or more) negative electrode current collectors 152 and one or more positive electrode current collectors 154.

[0019] In this embodiment, the cylindrical energy storage device 100 stores (sometimes referred to as charging) electrical energy supplied from an external electrical device (for example, a charging device, a power system, etc.). Examples of the electrical device include a power system, a power substation, a power distribution system, and a charging device. In this embodiment, the cylindrical energy storage device 100 supplies (sometimes referred to as discharging) electrical energy to the external electrical device. Examples of the electrical device include various devices that use or store electric power. In this specification, the discharging is sometimes referred to as power generation.

[0020] In this embodiment, the housing 110 accommodates the battery unit 150 therein. In this embodiment, the housing 110 has a tubular shape. The housing 110 may have a substantially cylindrical shape. The housing 110 may have a bottomed tubular shape with an opening formed at one end and a closed end at the other end.

[0021] In this embodiment, the tubular member 112 has a tubular shape. The tubular member 112 may have a substantially cylindrical shape. The tubular member 112 may be made of a conductive material. The tubular member 112 may be a tubular or hollow member made of metal.

[0022] In this embodiment, the bottom plate 114 closes one end of the cylindrical member 112. The bottom plate 114 may be made of a conductive material. This allows the bottom plate 114 to function as a negative electrode terminal of the cylindrical energy storage device 100.

[0023] In this embodiment, a sealing unit 130 is disposed in the opening 116. The battery unit 150 is housed inside the housing 110 by the cylindrical member 112, the bottom plate 114, and the sealing unit 130. The battery unit 150 may be sealed inside the housing 110.

[0024] In the present embodiment, the insulating member 120 is disposed on the inner surface of the cylindrical member 112. The insulating member 120 may be disposed in contact with the inner surface of the cylindrical member 112. The insulating member 120 is made of, for example, an insulating material. The insulating member 120 electrically insulates, for example, the cylindrical member 112 from the battery unit 150.

[0025] In this embodiment, the sealing unit 130 is disposed at one end of the cylindrical member 112 and seals the opening 116 of the cylindrical member 112. The sealing unit 130 may have a function of protecting the battery unit 150. A gasket 140 may be disposed between the sealing unit 130 and the cylindrical member 112. This allows the battery unit 150 to be sealed inside the housing 110. At least a portion of the sealing unit 130 may be made of a conductive material. This allows the sealing unit 130 to function as a positive terminal of the cylindrical energy storage device 100. Details of the sealing unit 130 will be described later.

[0026] In this embodiment, the battery unit 150 is disposed inside the housing 110. The battery unit 150 may be a structure in which one or more negative electrode current collectors 152 and one or more positive electrode current collectors 154 are stacked with an active material layer and a solid electrolyte layer interposed therebetween. Details of the battery unit 150 will be described later.

[0027] In this embodiment, the negative electrode wiring 162 electrically connects one or more negative electrode current collectors 152. In this embodiment, the positive electrode wiring 164 electrically connects one or more positive electrode current collectors 154. The positive electrode wiring 164 may be electrically connected to the sealing unit 130 via a positive electrode lead 170.

[0028] According to this embodiment, the negative electrode current collector 152 arranged on the bottom plate 114 side of the battery unit 150 (the lower side in the figure) comes into contact with the bottom plate 114. This electrically connects the one or more negative electrode current collectors 152 electrically connected by the negative electrode wiring 162 to the bottom plate 114. Furthermore, the one or more positive electrode current collectors 154 are electrically connected to the sealing unit 130, and as described above, the bottom plate 114 can be configured to function as a negative electrode terminal. The sealing unit 130 can be configured to function as a positive electrode terminal. This allows the cylindrical energy storage device 100 to function as an energy storage device.

[0029] In the present embodiment, the insulating member 166 is disposed between the sealing unit 130 and the battery unit 150. The insulating member 166 is made of, for example, an insulating material. The insulating member 166 electrically insulates, for example, the sealing unit 130 and the battery unit 150. Meanwhile, in the present embodiment, the positive electrode lead 170 electrically connects the sealing unit 130 and the battery unit 150.

[0030] As described above, in the cylindrical energy storage device 100 according to this embodiment, an insulating member 166 is disposed between the sealing unit 130, which functions as an input / output terminal, and the battery unit 150, which functions as a battery. In contrast, in a button battery and / or a coin battery, a positive electrode case that can function as a positive electrode terminal, a metal spring, and a laminate that functions as a battery are disposed in this order, and the positive electrode case and the laminate are electrically connected via the metal spring. Furthermore, the cylindrical energy storage device 100 according to this embodiment differs from a button battery and / or a coin battery in that it includes a sealing unit 130 that has a battery protection function.

[0031] (Electrical Characteristics of Cylindrical Energy Storage Device 100) In this embodiment, the capacity per unit area [mAh / cm ２ ] is calculated by dividing the area of ​​the housing 110 [cm ２ ] and the value [mAh / cm ４ The size of the cylindrical energy storage device 100 is determined so that the value of [parallel] (sometimes referred to as the capacity parameter) is 0.03 or more. This reduces variations in capacity per unit area in a direction (sometimes referred to as the planar direction) approximately perpendicular to the stacking direction (the up-and-down direction in the drawing) of the negative electrode current collector 152 and the positive electrode current collector 154 of the battery unit 150.

[0032] The value of the capacity parameter may be 0.05 or more, 0.07 or more, 0.1 or more, 0.15 or more, 0.20 or more, 0.75 or more, 1 or more.

[0033] In many cases, the internal surface area of ​​the housing 110 [cm ２ The size of the cylindrical energy storage device 100 is determined so that the capacity per unit area [mAh / cm 2 ] of the battery unit 150 is approximately equal to the cross-sectional area of ​​the battery unit 150. ２ ] is calculated by dividing the area of ​​the battery unit 150 [cm ２ ] and the value [mAh / cm ４] may be determined to be 0.03 or more. The above value may be 0.05 or more, 0.07 or more, 0.1 or more, 0.15 or more, or 0.20 or more.

[0034] In this embodiment, the area of ​​the battery unit 150 may be the area of ​​the battery unit 150 in a cross section obtained by cutting the battery unit 150 along a plane approximately perpendicular to the stacking direction (the up-and-down direction in the drawing) of the negative electrode current collector 152 and the positive electrode current collector 154 (this may also be referred to as the area when the battery unit 150 is cut along a plane approximately perpendicular to the stacking direction). When the cross-sectional shape of the battery unit 150 changes along the stacking direction, the area of ​​the battery unit 150 is calculated, for example, by the following procedure.

[0035] First, the cross-sectional area of ​​the battery unit 150 is determined at each of three positions that divide the entire length of the battery unit 150 in the stacking direction into approximately four equal parts. If the battery unit 150 is approximately cylindrical, the cross-sectional area is determined, for example, based on the measured diameter of the battery unit 150 at each position. Examples of the three positions include: (i) a first midpoint, which is the midpoint of the battery unit 150 in the stacking direction; (ii) a second midpoint, which is the midpoint between one end and the first midpoint; and (iii) a third midpoint, which is the midpoint between the other end and the first midpoint. Next, the cross-sectional areas at each of the three positions are averaged, and the average value is calculated as the cross-sectional area of ​​the battery unit 150.

[0036] In this embodiment, the area of ​​the housing 110 may be the internal area of ​​the cylindrical member 112 in a cross section obtained by cutting the cylindrical member 112 along a plane approximately perpendicular to the extension direction of the cylindrical member 112 (this may also be referred to as the area when the housing 110 is cut along a plane approximately perpendicular to the extension direction). When the cross-sectional shape of the cylindrical member 112 changes along the extension direction, the area of ​​the housing 110 is derived, for example, by the following procedure.

[0037] First, the cross-sectional area of ​​the tubular member 112 is determined at each of three positions that divide the entire length of the tubular member 112 in the extension direction into approximately four equal parts. The cross-sectional area of ​​the tubular member 112 is the area of ​​the inner portion of the inner wall of the tubular shape (sometimes referred to as the internal area). When the tubular member 112 is approximately cylindrical, the cross-sectional area is determined, for example, based on the measured value of the inner diameter of the tubular member 112 at each position. Examples of the three positions include (i) a first midpoint, which is the midpoint of the housing 110 in the extension direction; (ii) a second midpoint, which is the midpoint between one end and the first midpoint; and (iii) a third midpoint, which is the midpoint between the other end and the first midpoint. Next, the cross-sectional areas at each of the three positions are averaged, and the resulting average value is calculated as the internal area of ​​the cross section of the housing 110.

[0038] The area of ​​the housing 110 is 0.20 cm ２ 78.5cm or more ２ For example, when the cylindrical energy storage device 100 is a cylindrical AA battery, the area of ​​the housing 110 may be 0.47 cm ２ Similarly, when the cylindrical energy storage device 100 is a 4680-type cylindrical battery, the area of ​​the housing 110 is 16.6 cm ２ is.

[0039] In all-solid-state batteries that use a solid electrolyte layer as a separator, it is difficult to control the reaction at the interface between the active material layer and the solid electrolyte layer. Therefore, in batteries with a large area of ​​the laminate functioning as a battery, such as conventional prismatic batteries and / or pouch-shaped batteries, the interface area is large, and the unevenness of each layer significantly affects the battery characteristics. For example, the in-plane capacity per unit area varies greatly, resulting in a large variation in discharge capacity.

[0040] In contrast, the cylindrical energy storage device 100 according to this embodiment has a smaller area of ​​the laminate functioning as a battery than conventional prismatic batteries and / or pouch-type batteries. As a result, the capacity per unit area of ​​the battery unit 150 [mAh / cm ２ ] is calculated by dividing the area of ​​the housing 110 [cm ２ ] and the value [mAh / cm ４] is 0.03 or more. This can suppress the variation in capacity per unit area in the plane. As a result, for example, the variation in discharge capacity is suppressed.

[0041] The cylindrical energy storage device 100 may be an example of a battery. The cylindrical member 112 may be an example of a cylindrical portion. Of the ends of the cylindrical member 112, the end where the opening 116 is arranged may be an example of one end of a housing. Of the ends of the cylindrical member 112, the end where the bottom plate 114 is arranged may be an example of the other end of a housing. The bottom plate 114 may be an example of a second terminal portion. The insulating member 120 may be an example of a first insulating member. The sealing unit 130 may be an example of a first terminal portion or a sealing portion. The battery unit 150 may be an example of an electrode structure. The negative electrode wiring 162 may be an example of one of the first wiring and the second wiring. The positive electrode wiring 164 may be an example of the other of the first wiring and the second wiring. More specifically, the negative electrode wiring 162 may be an example of the first wiring, and the positive electrode wiring 164 may be an example of the second wiring. The insulating member 166 may be an example of a fourth insulating member. The positive electrode lead 170 may be an example of a connection portion. The positive electrode terminal may be an example of an input / output terminal. The negative electrode terminal may be an example of an input / output terminal.

[0042] 2 schematically shows an example of components of the sealing unit 130. In this embodiment, the sealing unit 130 seals the opening 116 of the housing 110. As described above, the sealing unit 130 functions as, for example, the positive electrode terminal of the cylindrical energy storage device 100. Specifically, the sealing unit 130 electrically connects an external electrical device (not shown) to the positive electrode current collector 154 of the battery unit 150.

[0043] In the present embodiment, the sealing unit 130 includes a positive electrode terminal plate 220, a protection unit 240, and a filter 260. For example, the positive electrode terminal plate 220, the protection unit 240, and the filter 260 are stacked in this order and then integrated by any method to produce the sealing unit 130. Examples of methods for integrating the positive electrode terminal plate 220, the protection unit 240, and the filter 260 include welding, screwing, and crimping.

[0044] In this embodiment, the positive electrode terminal plate 220 has a first surface 222 and a second surface 224. In this embodiment, the positive electrode terminal plate 220 has a protruding portion 226 that protrudes toward the first surface 222. In this embodiment, the positive electrode terminal plate 220 has an opening 228 that penetrates a portion of the positive electrode terminal plate 220. The opening 228 may be formed in the protruding portion 226.

[0045] According to the present embodiment, when the sealing unit 130 is assembled, the second surface 224 of the positive electrode terminal plate 220 comes into contact with the protection unit 240. In the present embodiment, the protrusion 226 is used, for example, as a positive electrode terminal of the cylindrical energy storage device 100. In the present embodiment, the opening 228 is used, for example, as a gas exhaust port for exhausting gas from inside the housing 110 to outside the housing 110 when the protection unit 240 is activated.

[0046] Each part of the positive electrode terminal plate 220 is made of, for example, a conductive material (sometimes referred to as a conductive material). Examples of conductive materials include metals or alloys such as aluminum, iron, copper, and nickel. The positive electrode terminal plate 220 may be made of a single type of conductive material, or may be made of multiple types of conductive materials. For example, the positive electrode terminal plate 220 is made by processing nickel-plated iron.

[0047] In this embodiment, the protection unit 240 has a valve body 242, a PTC element 244, and an inner cap 250. In this embodiment, the inner cap 250 includes a protrusion 256 that protrudes toward the valve body 242. In this embodiment, the inner cap 250 has an opening 258 that penetrates a portion of the inner cap 250. According to this embodiment, the valve body 242 and the inner cap 250 are joined at a joining region 257.

[0048] In this embodiment, the valve element 242, for example, separates the inside of the housing 110 from the outside of the housing 110. The valve element 242 blocks the movement of fluid between the inside of the housing 110 and the outside of the housing 110, and adjusts the amount of movement of the fluid (sometimes referred to as a flow rate). In this embodiment, the valve element 242 spontaneously opens as the pressure inside the housing 110 (sometimes referred to as an internal pressure) increases.

[0049] For example, if the internal pressure of the housing 110 increases for some reason, the valve body 242 expands toward the positive electrode terminal plate 220. If the internal pressure increases further, the connection between the valve body 242 and the inner cap 250 at the joint region 257 comes apart, and the current path between the valve body 242 and the inner cap 250 at the joint region 257 is interrupted. As a result, when the internal pressure of the cylindrical energy storage device 100 is greater than a predetermined value (sometimes referred to as a first threshold), the current between the battery unit 150 and the positive electrode terminal plate 220 can be limited.

[0050] If the internal pressure increases further, valve body 242 will rupture, allowing gas generated inside housing 110 to flow out of housing 110 through opening 228. As a result, damage to housing 110 due to an increase in the internal pressure of housing 110 is suppressed.

[0051] In this embodiment, the PTC element 244 is disposed between the valve body 242 and the inner cap 250. The PTC element 244 is in contact with, for example, the valve body 242 and the inner cap 250. The PTC element 244 has a positive temperature coefficient (PTC) and is used as an overcurrent protection element. The PTC element 244 may also be used as a resettable fuse.

[0052] The PTC element 244 exhibits a relatively small resistance value at temperatures around room temperature. When a current flows through the PTC element 244, the PTC element 244 generates heat by itself, and the temperature of the PTC element 244 increases. When the temperature of the PTC element 244 exceeds the Curie temperature, the resistance value of the PTC element 244 increases rapidly. For example, when an external short circuit occurs in the cylindrical energy storage device 100, the resistance value of the PTC element 244 increases. This interrupts the short-circuit current.

[0053] As described above, according to this embodiment, when the output current of the cylindrical energy storage device 100 is greater than a predetermined value (sometimes referred to as a second threshold), the current between the battery unit 150 and the positive electrode terminal plate 220 can be limited. This can protect the battery unit 150 from an overcurrent.

[0054] According to one embodiment, the current between the battery unit 150 and the positive terminal plate 220 is interrupted. According to another embodiment, an upper limit is set on the current between the battery unit 150 and the positive terminal plate 220. According to yet another embodiment, the output current is adjusted so that the current value is smaller than when the output current is equal to or less than the second threshold value.

[0055] In this embodiment, the inner cap 250 holds the valve body 242. As described above, the inner cap 250 is joined to the valve body 242 at the joining region 257. The method for joining the valve body 242 and the inner cap 250 is not particularly limited, but the valve body 242 and the inner cap 250 are joined by ultrasonic welding, for example. For example, when gas is generated inside the housing 110, the gas flows into the gap between the valve body 242 and the inner cap 250 through the opening 258. This causes the valve body 242 to bulge toward the positive electrode terminal plate 220.

[0056] Each of the valve body 242 and the inner cap 250 is made of, for example, a conductive material (sometimes referred to as a conductive material). Examples of conductive materials include metals or alloys such as aluminum, iron, copper, and nickel. Each of the valve body 242 and the inner cap 250 may be made of a single type of conductive material, or may be made of multiple types of conductive materials. For example, the valve body 242 and the inner cap 250 are made of aluminum.

[0057] In the present embodiment, the filter 260 has a first surface 262 and a second surface 264. In the present embodiment, the filter 260 has a protrusion 266 that protrudes toward the second surface 264. In the present embodiment, the filter 260 has an opening 268 that penetrates a portion of the filter 260. As a result, for example, when gas is generated inside the housing 110, the gas flows into the gap between the valve body 242 and the inner cap 250 through the opening 268 and the opening 258.

[0058] According to this embodiment, when the sealing unit 130 is assembled, the first surface 262 of the filter 260 comes into contact with the inner cap 250 of the protection unit 240. In this embodiment, the filter 260 is made of, for example, a conductive material (sometimes referred to as a conductive material). Examples of conductive materials include metals or alloys such as aluminum, iron, copper, and nickel. The filter 260 may be made of a single type of conductive material, or may be made of multiple types of conductive materials. For example, the filter 260 is made of aluminum.

[0059] The protection unit 240 may be an example of a restriction portion. The valve body 242 may be an example of a restriction portion. The PTC element 244 may be an example of a restriction portion.

[0060] (Outline of Battery Unit 150) The battery unit 150 will be described in detail with reference to Figures 3 and 4. Figure 3 schematically shows an example of the layered structure of the battery unit 150. Figure 4 schematically shows an example of basic battery elements that make up the battery unit 150.

[0061] 3 , in this embodiment, the battery unit 150 includes a laminate (sometimes referred to as a basic unit) having, in this order, an anode active material layer 310, a solid electrolyte layer 320, and a cathode active material layer 330. The basic unit is a basic battery element, and the basic unit functions as a battery by ion conduction between the anode active material layer 310 and the cathode active material layer 330, which face each other via the solid electrolyte layer 320.

[0062] The basic unit stores electrical energy supplied from an external electrical device to the cylindrical power storage device 100 (this may be referred to as charging the basic unit). The basic unit supplies electrical energy to an external electrical device (this may be referred to as discharging or generating electrical energy from the basic unit). Details of the basic unit will be described later.

[0063] In this embodiment, the battery unit 150 includes a plurality of basic units. Specifically, the battery unit 150 includes, in this order, an anode current collector 152, an anode active material layer 310, a solid electrolyte layer 320, a cathode active material layer 330, a cathode current collector 154, a cathode active material layer 330, a solid electrolyte layer 320, an anode active material layer 310, an anode current collector 152, an anode active material layer 310, a solid electrolyte layer 320, a cathode active material layer 330, a cathode current collector 154, a cathode active material layer 330, a solid electrolyte layer 320, an anode active material layer 310, and an anode current collector 152.

[0064] In this embodiment, the battery unit 150 further includes one or more insulating members 340. Each of the one or more insulating members 340 is disposed, for example, on a side surface of the battery unit 150. In this embodiment, the battery unit 150 further includes one or more insulating members 350. Each of the one or more insulating members 350 is disposed, for example, on a side surface of the battery unit 150. The side surface of the battery unit 150 is, for example, a surface that is approximately parallel to the stacking direction of the layers of the battery unit 150 (the up-and-down direction in the drawing).

[0065] In this embodiment, the negative electrode wiring 162 electrically connects the three negative electrode current collectors 152 included in the battery unit 150. The negative electrode wiring 162 is electrically connected to the bottom plate 114. In this embodiment, the positive electrode wiring 164 electrically connects the two positive electrode current collectors 154 included in the battery unit 150. The positive electrode wiring 164 is electrically connected to the sealing unit 130. Specifically, the positive electrode wiring 164 is electrically connected to the sealing unit 130 via a positive electrode lead 170.

[0066] In this embodiment, in order to facilitate understanding of the battery unit 150, the details of the battery unit 150 will be described using an example in which two adjacent layers are in contact. However, the battery unit 150 is not limited to this embodiment. The battery unit 150 may include any other layer as long as the function of the battery is not impaired. For example, according to another embodiment, another layer is disposed between the two layers that are considered to be adjacent in this embodiment.

[0067] As described above, in this embodiment, the battery unit 150 includes a plurality of basic units. In this embodiment, a negative electrode current collector 152 or a positive electrode current collector 154 is disposed between two adjacent basic units. A single basic unit is disposed between a pair of the negative electrode current collector 152 and the positive electrode current collector 154. Each of the plurality of basic units may be electrically connected in any manner by a negative electrode wiring 162 and a positive electrode wiring 164 disposed inside the housing 110.

[0068] 3, the battery unit 150 will be described in detail using an example in which four basic units are electrically connected in parallel, but the battery unit 150 is not limited to this embodiment.

[0069] In other embodiments, the number of basic units included in the battery unit 150 may be one, two, three, or five or more. Also, in other embodiments, two or more basic units may be electrically connected in series. In still other embodiments, two or more basic units may be electrically connected in parallel. In still other embodiments, two or more basic units that are electrically connected in parallel may be electrically connected in series with another basic unit.

[0070] (Details of Each Part of Battery Unit 150) In this embodiment, the negative electrode current collector 152 electrically connects the negative electrode active material layer 310 and the negative electrode terminal of the cylindrical power storage device 100. The negative electrode current collector 152 only needs to have conductivity according to the specifications of the cylindrical power storage device 100, and the size, structure, and material of the negative electrode current collector 152 are not particularly limited. Examples of the negative electrode current collector 152 include (i) a metal or conductive resin in the form of a plate, film, sheet, or foil, and (ii) a structure in which a metal layer is disposed on at least one surface of a plate, film, or sheet of resin. Examples of the metal include copper, aluminum, stainless steel, iron, nickel, titanium, and alloys thereof.

[0071] As described above, in the present embodiment, the bottom plate 114 of the casing 110 functions as the negative electrode terminal of the cylindrical energy storage device 100. In one embodiment, a portion of the negative electrode current collector 152 electrically connected to the negative electrode active material layer 310 comes into contact with the bottom plate 114, thereby electrically connecting the negative electrode active material layer 310 and the bottom plate 114. In another embodiment, a portion of the negative electrode current collector 152 electrically connected to the negative electrode active material layer 310 is electrically connected to the bottom plate 114 via the negative electrode wiring 162, thereby electrically connecting the negative electrode active material layer 310 and the bottom plate 114.

[0072] In this embodiment, the positive electrode current collector 154 electrically connects the positive electrode active material layer 330 and the positive electrode terminal of the cylindrical energy storage device 100. The positive electrode current collector 154 only needs to have conductivity according to the specifications of the cylindrical energy storage device 100, and the size, structure, and material of the positive electrode current collector 154 are not particularly limited. Examples of the positive electrode current collector 154 include (i) a metal or conductive resin in the form of a plate, film, sheet, or foil, and (ii) a structure in which a metal layer is disposed on at least one surface of a plate, film, or sheet of resin. Examples of the metal include copper, aluminum, stainless steel, iron, nickel, titanium, and alloys thereof.

[0073] As described above, in this embodiment, the positive electrode terminal plate 220 of the sealing unit 130 functions as the positive electrode terminal of the cylindrical energy storage device 100. The positive electrode current collector 154 is disposed, for example, between two positive electrode active material layers 330. The positive electrode current collector 154 is electrically connected to the positive electrode terminal plate 220, for example, via the positive electrode wiring 164 and the protection unit 240. This electrically connects the positive electrode active material layer 330 and the positive electrode terminal plate 220.

[0074] In this embodiment, the negative electrode active material layer 310 includes any type of negative electrode active material. As the negative electrode active material, for example, various materials capable of absorbing and releasing carrier ions of the cylindrical energy storage device 100 are used. The negative electrode active material may be an inorganic compound or an organic compound. These negative electrode active materials may be used alone, or two or more types of negative electrode active materials may be used in combination.

[0075] Examples of inorganic compounds (sometimes referred to as inorganic negative electrode active materials) used as the negative electrode active material include (i) carrier metals and alloys containing the carrier metals, (ii) tin, silicon, and alloys containing these, (iii) silicon oxides, and (iv) titanium oxides. For example, when the cylindrical energy storage device 100 is a lithium secondary battery, metallic lithium, lithium titanium oxide (LTO), or the like is used as the negative electrode active material. When a material not containing a carrier metal is used as the negative electrode active material, the material may be pre-doped with the carrier metal.

[0076] The organic compound used as the negative electrode active material (sometimes referred to as an organic negative electrode active material) includes various redox-active compounds, such as conjugated polymers, disulfides, quinones, localized radicals, and delocalized radicals.

[0077] The negative electrode active material layer 310 may further include at least one of a binder material, a conductive material, and an ion-conductive material in addition to the negative electrode active material. The negative electrode active material layer 310 may include one or more binder materials, one or more conductive materials, or one or more ion-conductive materials.

[0078] The binder material binds the materials that make up the negative electrode active material layer 310 and maintains the shape of the negative electrode active material layer 310. As the binder material, for example, various polymer materials are used. Examples of the polymer materials include carboxymethyl cellulose, styrene-butadiene rubber, polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), polyacrylic acid, polyethylene oxide (PEO), poly(3,4-ethylenedioxythiophene) (PEDOT), and derivatives thereof.

[0079] The conductive material improves the conductivity of the negative electrode active material layer 310. Examples of the conductive material include carbon-based materials, metal-based materials, and conductive polymer materials. Examples of the carbon-based material include graphite, carbon black (e.g., acetylene black, ketjen black, etc.), coke, amorphous carbon, carbon fiber, carbon nanotubes, and graphene. Examples of the metal-based material include aluminum, gold, silver, copper, iron, platinum, chromium, tin, indium, titanium, and nickel. Examples of the conductive polymer material include polyphenylene derivatives.

[0080] The ion-conductive material improves the conductivity of carrier ions in the negative electrode active material layer 310. As the ion-conductive material, for example, various solid electrolytes are used. Examples of the solid electrolyte include sulfide-based solid electrolytes, oxide-based solid electrolytes, and polymer solid electrolytes. Examples of the polymer solid electrolyte include polyethylene oxide (PEO), poly(3,4-ethylenedioxythiophene) (PEDOT), and at least one compound selected from derivatives thereof.

[0081] The negative electrode active material layer 310 may be a metal foil of the carrier metal of the cylindrical energy storage device 100. In this case, since the metal foil can function as the negative electrode current collector 152, the battery unit 150 does not need to include the negative electrode current collector 152.

[0082] In this embodiment, the solid electrolyte layer 320 contains a solid electrolyte as a main component. The solid electrolyte layer 320 contains, for example, more than 50 mass % of the solid electrolyte. The solid electrolyte layer 320 may contain, for example, 80 mass % or more of the solid electrolyte, or may contain 90 mass % or more of the solid electrolyte.

[0083] Examples of the solid electrolyte include sulfide-based solid electrolytes, oxide-based solid electrolytes, polymer solid electrolytes, etc. Examples of the polymer solid electrolyte include polyethylene oxide (PEO), poly(3,4-ethylenedioxythiophene) (PEDOT), and at least one compound selected from derivatives thereof.

[0084] The solid electrolyte layer 320 may contain a binder material, such as an insulating polymer material.

[0085] The solid electrolyte layer 320 functions as a separator between each basic unit. The solid electrolyte layer 320 has electrical insulation and ion conductivity. The solid electrolyte layer 320 electrically insulates the negative electrode active material layer 310 and the positive electrode active material layer 330. The solid electrolyte layer 320 conducts carrier ions between the negative electrode active material layer 310 and the positive electrode active material layer 330.

[0086] In this embodiment, the positive electrode active material layer 330 includes any type of positive electrode active material. As the positive electrode active material, for example, various materials capable of absorbing and releasing carrier ions of the cylindrical energy storage device 100 are used. The positive electrode active material may be an inorganic compound or an organic compound. These positive electrode active materials may be used alone, or two or more types of positive electrode active materials may be used in combination.

[0087] Examples of inorganic compounds used as the positive electrode active material (sometimes referred to as inorganic positive electrode active materials) include metal oxides, metal silicates, metal phosphates, metal borates, etc. Examples of the metals include transition metals such as V, Mn, Ni, and Co.

[0088] The organic compound used as the positive electrode active material (sometimes referred to as an organic positive electrode active material) includes various redox-active compounds, such as conjugated polymers, disulfides, quinones, localized radicals, and delocalized radicals.

[0089] The positive electrode active material layer 330 may further include at least one of a binder material, a conductive material, and an ion conductive material in addition to the positive electrode active material. The positive electrode active material layer 330 may include one or more binder materials, one or more conductive materials, or one or more ion conductive materials. The binder material may be the binder material described in relation to the negative electrode active material layer 310. The conductive material may be the conductive material described in relation to the negative electrode active material layer 310. The ion conductive material may be the ion conductive material described in relation to the negative electrode active material layer 310.

[0090] In the present embodiment, the insulating member 340 is made of an insulating material. The insulating member 340 electrically insulates the positive electrode current collector 154 from the negative electrode wiring 162. The insulating member 340 is arranged, for example, to cover at least a portion of the end of the positive electrode current collector 154 that contacts the positive electrode active material layer 330. The insulating member 340 is arranged, for example, to cover the positive electrode current collector 154 that is exposed from the side surface of the battery unit 150 and is located near the negative electrode wiring 162. The insulating member 340 is arranged, for example, to cover at least a portion of the end of the positive electrode current collector 154 that is disposed between two positive electrode active material layers 330. The insulating member 340 is arranged, for example, to cover at least a portion of the end of the positive electrode current collector 154 that is exposed between two positive electrode active material layers 330.

[0091] The insulating member 340 is disposed between the positive electrode current collector 154 and the negative electrode wiring 162. The insulating member 340 may be disposed so as to surround the side surfaces of the two positive electrode active material layers 330. The insulating member 340 may be disposed so as to cover the regions of the side surfaces of the two positive electrode active material layers 330 that are located near the negative electrode wiring 162.

[0092] In the present embodiment, the insulating member 350 is made of an insulating material. The insulating member 350 electrically insulates the negative electrode current collector 152 from the positive electrode wiring 164. The insulating member 350 is arranged, for example, to cover at least a portion of the end of the negative electrode current collector 152 that contacts the negative electrode active material layer 310. The insulating member 350 is arranged, for example, to cover the negative electrode current collector 152 that is exposed from the side surface of the battery unit 150 and is located near the positive electrode wiring 164. The insulating member 350 is arranged, for example, to cover at least a portion of the end of the negative electrode current collector 152 that is disposed between two negative electrode active material layers 310. The insulating member 350 is arranged, for example, to cover at least a portion of the end of the negative electrode current collector 152 that is exposed between two negative electrode active material layers 310.

[0093] The insulating member 350 is disposed between the negative electrode current collector 152 and the positive electrode wire 164. The insulating member 350 may be disposed so as to surround the side surfaces of the two negative electrode active material layers 310. The insulating member 350 may be disposed so as to cover regions of the side surfaces of the two negative electrode active material layers 310 that are located near the positive electrode wire 164.

[0094] The negative electrode active material layer 310 may be an example of one of the first active material layer and the second active material layer. The positive electrode active material layer 330 may be an example of the other of the first active material layer and the second active material layer. More specifically, the negative electrode active material layer 310 may be an example of the first active material layer, and the positive electrode active material layer 330 may be an example of the second active material layer. The insulating member 340 may be an example of one of the second insulating member and the third insulating member. The insulating member 350 may be an example of the other of the second insulating member and the third insulating member. More specifically, the insulating member 340 may be an example of the second insulating member, and the insulating member 350 may be an example of the third insulating member.

[0095] The negative electrode current collector 152 may be an example of a first current collector, and the positive electrode current collector 154 may be an example of a second current collector. Each of the three negative electrode current collectors 152 included in the battery unit 150 may be an example of a first current collector, a third current collector, or a fifth current collector. Each of the two positive electrode current collectors 154 included in the battery unit 150 may be an example of a second current collector or a fourth current collector. Each of the four basic units included in the battery unit 150 may be an example of a first power generating element, a second power generating element, a third power generating element, or a fourth power generating element.

[0096] 4 schematically shows an example of basic battery elements (sometimes referred to as basic units) that make up the battery unit 150. In this embodiment, the battery unit 150 includes a plurality of basic units, including a basic unit 422 and a basic unit 442. In this embodiment, the basic unit 422 includes an anode active material layer 310, a solid electrolyte layer 320, and a cathode active material layer 330, in this order. Similarly, the basic unit 442 includes an anode active material layer 310, a solid electrolyte layer 320, and a cathode active material layer 330, in this order.

[0097] In this embodiment, the basic unit 422 is disposed between the negative electrode current collector 152 and the positive electrode current collector 154. This forms an element 420 that functions as a battery. Similarly, the basic unit 442 is disposed between the negative electrode current collector 152 and the positive electrode current collector 154. This forms an element 440 that functions as a battery.

[0098] In this embodiment, the positive electrode active material layer 330 of the basic unit 422 and the positive electrode active material layer 330 of the basic unit 442 are disposed so as to face each other across the single positive electrode current collector 154. This results in a structure in which two basic units are stacked.

[0099] The basic unit 422 may be an example of a power generating element. The basic unit 422 may be an example of one of the first power generating element and the second power generating element. The basic unit 442 may be an example of a power generating element. The basic unit 442 may be an example of the other of the first power generating element and the second power generating element.

[0100] 5 schematically shows an example of a stacked structure of a battery unit 500 (stacked body). The battery unit 500 may be an example of a structure in which a plurality of battery units 150 are electrically connected in series. In this embodiment, the battery unit 500 includes a battery unit 150 and a battery unit 550. The battery unit 550 may have a similar configuration to the battery unit 150.

[0101] In this embodiment, the positive electrode wiring 164 of the battery unit 550 is electrically connected to the positive electrode terminal of the cylindrical energy storage device 100. Specifically, the positive electrode wiring 164 of the battery unit 550 is electrically connected to the sealing unit 130 via a positive electrode lead 170. On the other hand, the negative electrode wiring 162 of the battery unit 150 is electrically connected to the negative electrode terminal of the cylindrical energy storage device 100. Specifically, the negative electrode wiring 162 of the battery unit 150 is physically connected to 114 of the housing 110.

[0102] In this embodiment, the battery unit 550 includes a connection wiring 560 that electrically connects the positive electrode wiring 164 of the battery unit 150 and the negative electrode wiring 162 of the battery unit 550. As described above, the battery unit 150 has four basic units electrically connected in parallel. By electrically connecting the positive electrode wiring 164 of the battery unit 150 and the negative electrode wiring 162 of the battery unit 550, a battery is obtained in which the four basic units electrically connected in parallel and the four basic units electrically connected in parallel are electrically connected in series.

[0103] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0104] (Example 1) (Production of battery element) As a positive electrode active material, LiNi １／３ Mn １／３ Co １／３ O ２ (sometimes referred to as NCM) was prepared. Lithium phosphorus sulfur chloride (sometimes referred to as LPSCl) was prepared as a sulfide-based solid electrolyte. Carbon black was prepared as a conductive additive. Next, 18.0 g of NCM, 6.0 g of LPSCl, and 0.3 g of carbon black were mixed to prepare a positive electrode mixture.

[0105] A circular aluminum foil with a diameter of 17.1 mm was prepared as the positive electrode current collector. A circular lithium metal foil (purity 99.5% or higher) with a thickness of 20 μm and a diameter of 17.1 mm was prepared as the negative electrode active material. A circular copper foil with a diameter of 17.1 mm was prepared as the negative electrode current collector.

[0106] Next, a cylindrical container with both ends open was prepared. The inner diameter of the container was 17.1 mm. In a glove box under an argon atmosphere, 0.01 g of LPSCl was placed inside the container and pressed at a pressure of 1 ton. This formed a solid electrolyte layer inside the container.

[0107] Next, 0.18 g of the above-described positive electrode mixture was placed into the container through one opening and pressed under a pressure of 6 tons. As a result, a positive electrode active material layer was formed on one side of the solid electrolyte layer inside the container. Next, aluminum foil was inserted into the container through the opening as a positive electrode current collector.

[0108] Next, lithium metal as the negative electrode active material and copper foil as the negative electrode current collector were inserted into the container through the opening on the other side. The contents of the container were then pressed under a pressure of 1 ton. This resulted in a battery element having a positive electrode current collector foil, a positive electrode active material layer, a solid electrolyte, a metallic lithium layer, and a negative electrode current collector foil in this order. Eight battery elements were fabricated using the same procedure.

[0109] (Manufacturing of Battery Units) Using the eight battery elements manufactured by the above-described procedure, a first battery unit having four stacked battery elements and a second battery unit having four stacked battery elements were manufactured. Each of the first battery unit and the second battery unit was manufactured by the following procedure.

[0110] First, two battery elements were stacked so that the positive electrodes of the two battery elements overlapped each other. Similarly, two other battery elements were stacked so that the positive electrodes of the other two battery elements overlapped each other. This resulted in two sets of two-battery element stacks (sometimes referred to as bi-connected bodies). Next, the two bi-connected bodies were stacked so that the negative electrodes of the two bi-connected bodies overlapped each other.

[0111] Next, the positive electrode current collectors included in the two stacked two-connected bodies were connected with an aluminum tab. The negative electrode current collectors included in the two stacked two-connected bodies were connected with a copper tab. Furthermore, an insulating film was placed on the side of the two stacked two-connected bodies to prevent direct contact between the two stacked two-connected bodies and the aluminum tab. Similarly, an insulating film was placed on the side of the two stacked two-connected bodies to prevent direct contact between the two stacked two-connected bodies and the copper tab. This resulted in a battery unit having a similar configuration to the battery unit 150 described above. A first battery unit and a second battery unit were obtained by repeating the same procedure.

[0112] (Manufacturing of Cylindrical All-Solid-State Battery) The first and second battery units fabricated by the above-described procedure were stacked with an insulating film interposed therebetween. Next, the negative electrode tab (part of the negative electrode current collector) of the first battery unit and the positive electrode tab (part of the positive electrode current collector) of the second battery unit were connected with a copper tab. This resulted in a battery structure having a configuration similar to that of battery unit 500.

[0113] Next, a sealing body having a configuration similar to that of the above-described sealing unit 130 was prepared. In addition, the negative electrode tab (part of the negative electrode current collector) of the second battery unit included in the above-described battery structure was connected to the sealing body with an aluminum tab.

[0114] Next, a cylindrical metal case with an outer diameter of 18 mm and a height of 10 mm was prepared. A bottom plate functioning as a negative electrode terminal was disposed at one end of the metal case. An opening was formed at the other end of the metal case.

[0115] Next, an insulating film was placed between the battery structure and the sealing member, and the battery structure was then housed inside a metal case so that the negative electrode side of the battery structure was in contact with the bottom plate of the metal case. A gasket was placed in the opening of the metal case, and the opening of the metal case was sealed using the sealing member connected to the battery structure. This resulted in a cylindrical all-solid-state battery. 100 cylindrical all-solid-state batteries were produced using the same procedure.

[0116] (Examples 2 to 9 and Comparative Example 1) 100 cylindrical all-solid-state batteries were fabricated in each example by the same procedure as in Example 1, except that the inner diameter of the battery element container and the diameter of each part of the battery element were changed. As described above, the diameter of each part of the battery element was approximately the same as the inner diameter of the battery element container. (i) The inner area [cm ２ ] and (ii) the design capacity per unit area of ​​the battery element of each example [mAh / cm ２ ] is the inner surface area [cm 2 ] of the container of the battery element of each example. ２ ] and the value obtained by dividing by [mAh / cm ４] are shown in Table 1. As described above, the index obtained by dividing the design capacity per unit area of ​​the battery element by the inner area of ​​the container of the battery element is called a capacity parameter.

[0117]

[0118] (Evaluation) For each Example and Comparative Example, a charge / discharge test was performed on 100 cylindrical all-solid-state batteries fabricated in each Example to determine the discharge capacity of each battery. The standard deviation of the discharge capacities of the 100 cylindrical all-solid-state batteries was calculated. In each Example and Comparative Example, batteries whose discharge capacity was less than 99.8% of the design capacity were counted as defective batteries.

[0119] The charge / discharge test was carried out according to the following procedure. First, in a thermostatic chamber at 25°C, the batteries of the examples and comparative examples were charged under constant current conditions at a current density of 0.1 C C rate until a voltage of 4.3 V was reached. Next, they were discharged under constant current conditions at a current density of 0.1 C until a voltage of 3.0 V was reached. The above charge / discharge cycle was carried out three times, and the discharge capacity at the third cycle was determined as the discharge capacity for each example.

[0120] The standard deviation of the discharge capacity in each example and comparative example is shown in Table 1. The number of defective batteries in each example and comparative example is also shown in Table 1. As shown in Table 1, the value of the capacity parameter was 0.03 mAh / cm ４ It can be seen that the standard deviation of the discharge capacity is very small when the capacity parameter value is 0.03 mAh / cm or more. ４ If this is the case, it is clear that the number of defective batteries is very small.

[0121] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0122] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order.

[0123] REFERENCE SIGNS LIST 100 Cylindrical energy storage device, 110 Housing, 112 Cylindrical member, 114 Bottom plate, 116 Opening, 120 Insulating member, 130 Sealing unit, 140 Gasket, 150 Battery unit, 152 Negative electrode current collector, 154 Positive electrode current collector, 162 Negative electrode wiring, 164 Positive electrode wiring, 166 Insulating member, 170 Positive electrode lead, 220 Positive electrode terminal plate, 222 First surface, 224 Second surface, 226 Protrusion, 228 Opening, 240 Protection unit, 242 Valve body, 244 PTC element, 250 Inner cap, 256 Protrusion, 257 Bonding region, 258 Opening, 260 Filter, 262 First surface, 264 Second surface, 266 Protrusion, 268 Opening, 310 Negative electrode active material layer, 320 solid electrolyte layer, 330 positive electrode active material layer, 340 insulating member, 350 insulating member, 420 element, 422 basic unit, 440 element, 442 basic unit, 500 battery unit, 550 battery unit, 560 connecting wiring

Claims

1. A battery comprising: a cylindrical housing having an opening at one end; an electrode structure disposed inside the housing; a sealing portion that seals the opening of the housing; and a connection portion that electrically connects the electrode structure and the sealing portion, wherein the sealing portion has: a first terminal portion that functions as an input / output terminal of the battery; and a limiting portion that limits a current between the electrode structure and the first terminal portion when the internal pressure of the battery is greater than a predetermined first threshold value or when the output current of the battery is greater than a predetermined second threshold value, wherein the electrode structure has a power generation element including a first active material layer, a solid electrolyte layer, and a second active material layer in this order, and wherein the capacity per unit area of ​​the power generation element [mAh / cm] is ２ ] to the area of ​​the housing [cm ２ ] and the value [mAh / cm ４ ] is 0.03 or more, the area of ​​the power generating element is the area when the power generating element is cut along a plane approximately perpendicular to the stacking direction of the first active material layer, the solid electrolyte layer, and the second active material layer, and the area of ​​the casing is the area when the casing is cut along a plane approximately perpendicular to the extension direction of the cylindrical shape.

2. The area of ​​the housing is 0.20 cm ２ 78.5cm or more ２ 10. The battery of claim 1, wherein:

3. The battery according to claim 1, wherein the housing has: a conductive cylindrical portion having a substantially cylindrical shape; and a first insulating member disposed on the inner surface of the cylindrical portion.

4. The battery according to claim 1, wherein the electrode structure has a plurality of the power generating elements electrically connected in series and / or parallel.

5. The battery according to claim 4, wherein the plurality of power generating elements include a first power generating element and a second power generating element; the electrode structure has a first current collector, the first power generating element, a second current collector, and the second power generating element in this order; the second current collector is disposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element; and the electrode structure further has a second insulating member covering at least a portion of the second current collector exposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element.

6. The battery according to claim 5, further comprising a second terminal portion that seals the other end of the casing and functions as an input / output terminal of the battery, wherein the first current collector is electrically connected to the second terminal portion, and the second current collector is electrically connected to the first terminal portion via the connecting portion and the limiting portion.

7. The battery according to claim 5, wherein the electrode structure has the first current collector, the first power generating element, the second current collector, the second power generating element, and a third current collector in this order, the electrode structure further has a first wiring that electrically connects the first current collector and the third current collector, the second insulating member is disposed between the first wiring and the second current collector, and the first power generating element and the second power generating element are electrically connected in parallel.

8. A battery comprising: a cylindrical casing having an opening at one end; and an electrode structure disposed inside the casing, wherein the electrode structure has a first current collector, a first power generating element, a second current collector, a second power generating element, and a third current collector, in this order; each of the first power generating element and the second power generating element includes a first active material layer, a solid electrolyte layer, and a second active material layer, in this order; the second current collector is disposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element; the electrode structure further has: a second insulating member covering at least a portion of an end of the second current collector disposed between the second active material layer of the first power generating element and the second active material layer of the second power generating element; and a first wiring electrically connecting the first current collector and the third current collector; the second insulating member is disposed between the first wiring and the second current collector; and the first power generating element and the second power generating element are electrically connected in parallel.

9. The battery according to claim 8, wherein the battery further comprises a conductive sealing portion that seals the opening of the casing, and the electrode structure further comprises a third insulating member that covers at least a portion of the end of the first current collector that contacts the first active material layer of the first power generating element and / or the second power generating element, and a second wiring that electrically connects the second current collector and the sealing portion, and the third insulating member is disposed between the second wiring and the first current collector.

10. The electrode structure has a first battery unit, a fourth insulating member, and a second battery unit in this order; each of the first battery unit and the second battery unit has, in this order, the first current collector, the first power generating element, the second current collector, the second power generating element, the third current collector, the third power generating element, the fourth current collector, the fourth power generating element, and a fifth current collector; each of the third power generating element and the fourth power generating element includes, in this order, the first active material layer, the solid electrolyte layer, and the second active material layer; the third current collector is disposed between the first active material layer of the second power generating element and the first active material layer of the third power generating element; the fourth current collector is disposed between the second active material layer of the third power generating element and the second active material layer of the fourth power generating element; the first battery unit and the second battery unit are electrically connected in series; The battery according to claim 8 , wherein the first power generation element, the second power generation element, the third power generation element, and the fourth power generation element included in the first battery unit are electrically connected in parallel, and the first power generation element, the second power generation element, the third power generation element, and the fourth power generation element included in the second battery unit are electrically connected in parallel.

11. The battery according to claim 8, wherein the housing has: a conductive cylindrical portion having a substantially cylindrical shape; and a first insulating member disposed on the inner surface of the cylindrical portion.

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