Stacked battery
Disclosed is a stacked battery that can flow a larger rounding current in a short-circuit current shunt part than in an electric element when a short circuit occurs in the short-circuit current shunt part and the electric element in nailing, the stacked battery in which an electrical resistance of a current collector tab of the short-circuit current shunt part is smaller than an electrical resistance of a current collector tab of the electric element.
1. A stacked battery comprising a stack of: at least one short-circuit current shunt part; and a plurality of electric elements,
wherein:
the short-circuit current shunt part comprises a first current collector layer, a first insulating layer, a second current collector layer, a second insulating layer, and another first current collector, all these layers being stacked in that order;
each of the first current collector layer comprises a first current collector tab;
the second current collector layer comprises a second current collector tab;
each electric element comprises a cathode current collector layer, a cathode material layer, an electrolyte layer, an anode material layer, and an anode current collector layer, all these layers being stacked each other;
the cathode current collector layer comprises a cathode current collector tab;
the anode current collector layer comprises an anode current collector tab;
the electric elements are connected to each other electrically in parallel by an electrical connection of a plurality of the cathode current collector tabs and an electrical connection of a plurality of the anode current collector tabs;
each of the first current collector layer is electrically connected to the cathode current collector layer via the first current collector tab;
the second current collector layer is electrically connected to the anode current collector layer via the second current collector tab; and
a sum of an electrical resistance of the first current collector tab and an electrical resistance of the second current collector tab is smaller than a sum of an electrical resistance of the cathode current collector tab and an electrical resistance of the anode current collector tab.
2. The stacked battery according to claim 1 , wherein a specific resistance of the first current collector tab is smaller than a specific resistance of the cathode current collector tab, and a specific resistance of the second current collector tab is smaller than a specific resistance of the anode current collector tab.
3. The stacked battery according to claim 1 ,
wherein:
the cathode current collector tabs and the anode current collector tabs have portions projecting from the stack;
a layer formed of a material larger in specific resistance than the cathode current collector tab is provided between the portions of the cathode current collector tabs; and
a layer formed of a material lager in specific resistance than the anode current collector tab is provided between the portions of the anode current collector tabs.
4. The stacked battery according to claim 1 , comprising a plurality of the short-circuit current shunt parts,
wherein:
the first current collector tabs and the second current collector tabs have portions projecting from the stack;
a layer formed of a same material as the first current collector tab is provided between the portions of the first current collector tabs, and the layer is joined to the first current collector tabs by welding;
a layer formed of a same material as the second current collector tab is provided between the portions of the second current collector tabs, and the layer is joined to the second current collector tabs by welding;
the cathode current collector tabs and the anode current collector tabs have portions projecting from the stack;
a layer formed of a same material as the cathode current collector tab is provided between the portions of the cathode current collector tabs, and the layer is joined to the cathode current collector tabs by welding;
a layer formed of a same material as the anode current collector tab is provided between the portions of the anode current collector tabs, and the layer is joined to the anode current collector tabs by welding;
an area where the first current collector tab is welded is larger than an area where the cathode current collector tab is welded; and
an area where the second current collector tab is welded is larger than an area where the anode current collector tab is welded.
5. The stacked battery according to claim 1 , wherein the first current collector tab is larger than the cathode current collector tab in thickness, and the second current collector tab is larger than the anode current collector tab in thickness.
6. The stacked battery according to claim 1 , wherein the first current collector tab is larger than the cathode current collector tab in width, and the second current collector tab is larger than the anode current collector tab in width.
7. The stacked battery according to claim 1 , wherein two electric elements share one anode current collector layer, and
wherein the cathode current collector layer, the cathode material layer, the electrolyte layer, the anode material layer, the anode current collector layer, another anode material layer, another electrolyte layer, another cathode material layer, and another cathode current collector layer are directly stacked in that order.