Safety battery rubber nail and battery cover plate applied to lithium supplement battery

The utility model discloses a safety battery rubber nail applied to a lithium battery. The safety battery rubber nail comprises a nail body, a conical insertion part is arranged at the bottom end of the nail body; the conical insertion part is used for being inserted into a liquid injection hole of a battery cover plate of the lithium supplement battery; a gas conveying through hole is formed in the middle of the conical insertion part; a second gas discharge cavity and a first gas discharge cavity which are distributed up and down are formed in the nail body and are separated by a partition plate; a plurality of exhaust holes are formed in the top of the nail body; the top of the gas conveying through hole is communicated with the first gas discharging cavity; the bottom of the gas conveying through hole is connected with the interior of the lithium supplement battery; a vent hole is formed in the middle of the partition plate; a spring is arranged above the vent hole; the upper end of the spring is connecte