Battery casing, method for manufacturing the same, and device containing battery casing
The present disclosure discloses a battery casing, a method for manufacturing the same, and a device including a battery casing. A battery casing includes a casing body, a plurality of battery cells accommodated in the casing body, and a fire protection plate which is disposed inside the casing body at least corresponding to the plurality of battery cells and includes a thermal aerosol fire protection layer which includes an aerosol generating agent, wherein a total mass A of the aerosol generating agent in the casing body and a free space volume B of the casing body satisfy a relationship as represented by 0.03 g/L≤A/B≤8 g/L.
1. A battery casing, comprising a casing body, a plurality of battery cells accommodated in the casing body, and a fire protection plate which is disposed inside the casing body, at least disposed corresponding to the plurality of battery cells, and comprises a thermal aerosol fire protection layer which comprises an aerosol generating agent, the aerosol generating agent comprising an oxidant, a combustible agent, and a binder, the oxidant comprising one or more of nitrate, halogen acid salt, and perhalic acid salt, the combustible agent comprising one or more of an organic combustible agent and an inorganic combustible agent, and the aerosol generating agent comprising 50-80 parts by weight of the oxidant, 10-35 parts by weight of the combustible agent, and 1-5 parts by weight of the binder,
characterized in that a total mass A of the aerosol generating agent in the casing body and a free space volume B of the casing body satisfy a relationship as represented by 0.03 g/L≤A/B≤8 g/L, a free space of the casing body refers to a remaining space except the space occupied by the plurality of battery cells in the space enclosed by the casing body, the fire protection plate, and other accessories, and the free space volume B of the casing body is a volume of the remaining space.
2. The battery casing according to claim 1 , wherein the total mass A and the free space volume B satisfy a relationship as represented by 0.03 g/L≤A/B≤4 g/L.
3. The battery casing according to claim 1 , wherein the aerosol generating agent satisfies at least one of the following:
the nitrate is selected from one or more of sodium nitrate, potassium nitrate, strontium nitrate, and ammonium nitrate;
the halogen acid salt is selected from one or more of potassium halate and sodium halate;
the perhalic acid salt is selected from one or more of potassium perhalate and sodium perhalate;
the organic combustible agent is selected from a solid organic compound;
the inorganic combustible agent is selected from one or more of phosphorus, sulfur, a carbon-based combustible agent and a metal-based combustible agent; and
the binder comprises one or more of a natural resin and a synthetic resin.
4. The battery casing according to claim 1 , wherein the aerosol generating agent further comprises an additive, which comprises one or more of carbonate, bicarbonate, metal halide, ammonium halide, and metal oxide.
5. The battery casing according to claim 4 , wherein the aerosol generating agent comprises less than or equal to 20 parts by weight of the additive.
6. The battery casing according to claim 1 , wherein the thermal aerosol fire protection layer further comprises an accelerant which comprises one or more of nitrocellulose, celluloid, sulfur, and camphor.
7. The battery casing according to claim 6 , wherein the accelerant is present in the thermal aerosol fire protection layer in percentage by weight of 0.5%-10%.
8. The battery casing according to claim 1 , wherein the fire protection plate further comprises an accelerant layer, the accelerant layer stacked with the thermal aerosol fire protection layer, and/or the accelerant layer disposed on at least one side of the thermal aerosol fire protection layer; and
the accelerant layer comprises one or more of nitrocellulose, celluloid, sulfur, and camphor.
9. The battery casing according to claim 1 , wherein encapsulating layers are disposed on opposite two sides of the fire protection plate in its own thickness direction so as to isolate and protect a structure between the encapsulating layers on the two sides.
10. The battery casing according to claim 1 , wherein there are one or more fire protection plates inside the casing body, and in the case where there are more than one fire protection plate in the casing body, each of the fire protection plates is disposed corresponding to at least one of the plurality of battery cells.
11. The battery casing according to claim 1 , wherein the battery casing further satisfies at least one of the following:
the fire protection plate is disposed between at least two adjacent ones of the plurality of battery cells;
the fire protection plate is disposed on at least one side of at least one of the plurality of battery cells in a width direction of a corresponding one of the plurality of battery cells;
the fire protection plate is disposed on a side of the at least one of the plurality of battery cells where an explosion-proof valve is located; and
the fire protection plate is disposed on an inner side wall and/or an inner top wall of the casing body.
12. The battery casing according to claim 1 , wherein a buffering separation plate is disposed between every two adjacent ones of the plurality of battery cells, the buffering separation plate is disposed with an accommodating portion comprising an opening, and the fire protection plate is disposed in the accommodating portion.
13. A device comprising a battery casing according to claim 1 .