Stacked battery
An objective of the present disclosure is to provide a stacked battery that suppresses sneak current caused by an unevenness of a short circuit resistance among a plurality of cells. The present disclosure provides a stacked battery comprising: a plurality of cells in a thickness direction, wherein the plurality of cells are electrically connected in parallel; the stacked battery includes a surface-side cell that is located on a surface side of the stacked battery, and a center-side cell that is located on a center side rather than the surface-side cell; wherein a resistance of the cathode current collecting tab in the surface-side cell is more than a resistance of the cathode current collecting tab in the center-side cell; or a resistance of the anode current collecting tab in the surface-side cell is more than a resistance of the anode current collecting tab in the center-side cell.
1. A stacked battery comprising:
a plurality of cells in a thickness direction, wherein
the plurality of cells are electrically connected in parallel;
each of the plurality of cells includes a cathode current collector with a cathode current collecting tab, a cathode active material layer, a solid electrolyte layer, an anode active material layer, and an anode current collector with an anode current collecting tab, in this order;
the stacked battery includes a surface-side cell that is located on a surface side of the stacked battery, and a center-side cell that is located on a center side rather than the surface-side cell;
an area in plan view of the cathode current collecting tab in the surface-side cell is less than an area in plan view of the cathode current collecting tab in the center-side cell; and
the surface-side cell and the center-side cell satisfy at least one of:
condition i) a resistance of the cathode current collecting tab in the surface-side cell is more than a resistance of the cathode current collecting tab in the center-side cell; and
condition ii) a resistance of the anode current collecting tab in the surface-side cell is more than a resistance of the anode current collecting tab in the center-side cell.
2. The stacked battery according to claim 1 , wherein a specific resistance of the cathode current collecting tab in the surface-side cell is more than a specific resistance of the cathode current collecting tab in the center-side cell.
3. The stacked battery according to claim 1 , wherein a specific resistance of the anode current collecting tab in the surface-side cell is more than a specific resistance of the anode current collecting tab in the center-side cell.
4. The stacked battery according to claim 1 , wherein a thickness of the cathode current collecting tab in the surface-side cell is less than a thickness of the cathode current collecting tab in the center-side cell.
5. The stacked battery according to claim 1 , wherein a thickness of the anode current collecting tab in the surface-side cell is less than a thickness of the anode current collecting tab in the center-side cell.
6. The stacked battery according to claim 1 , wherein an area of the anode current collecting tab in the surface-side cell is less than an area of the anode current collecting tab in the center-side cell.
7. The stacked battery according to claim 1 , wherein the cathode current collecting tab in the surface-side cell includes a resistor on at least one surface side.
8. The stacked battery according to claim 1 , wherein the anode current collecting tab in the surface-side cell includes a resistor on at least one surface side.
9. The stacked battery according to claim 1 , wherein an area of a welded portion in contact with the cathode current collecting tab in the surface-side cell is less than an area of a welded portion in contact with the cathode current collecting tab in the center-side cell.
10. The stacked battery according claim 1 , wherein an area of a welded portion in contact with the anode current collecting tab in the surface-side cell is less than an area of a welded portion in contact with the anode current collecting tab in the center-side cell.
11. The stacked battery according to claim 1 , wherein, when each of the plurality of cells is numbered as 1 st cell to N th cell, in which N≥3, in order along the thickness direction of the stacked battery,
the surface-side cell is a cell that belongs to a cell region A including 1 st cell to (N/3) th cell.
12. The stacked battery according to claim 11 , wherein the center-side cell is a cell that belongs to a cell region B including ((N/3)+1) th cell to (2N/3) th cell.
13. The stacked battery according to claim 12 , wherein an average resistance of the cathode current collecting tab in the cell region A is more than an average resistance of the cathode current collecting tab in the cell region B.
14. The stacked battery according to claim 12 , wherein an average resistance of the anode current collecting tab in the cell region A is more than an average resistance of the anode current collecting tab in the cell region B.
15. The stacked battery according to claim 1 , wherein, when each of the plurality of cells is numbered as 1 st cell to N th cell, in which N≥60, in order along the thickness direction of the stacked battery,
the surface-side cell is a cell that belongs to a cell region C including 1 st cell to 20 th cell.
16. The stacked battery according to claim 15 , wherein the center-side cell is a cell that belongs to a cell region D including 21 st cell to 40 th cell.
17. The stacked battery according to claim 16 , wherein an average resistance of the cathode current collecting tab in the cell region C is more than an average resistance of the cathode current collecting tab in the cell region D.
18. The stacked battery according to claim 16 , wherein an average resistance of the anode current collecting tab in the cell region C is more than an average resistance of the anode current collecting tab in the cell region D.
19. The stacked battery according to claim 1 , wherein the anode active material layer includes Si or a Si alloy as an anode active material.