The application relates to the technical field of batteries, in particular to a battery cover plate and a battery. The battery cover plate comprises a base plate and a sealing nail. The base plate is provided with a
liquid injection hole, and the sealing nail is connected in the
liquid injection hole. The sealing nail is provided with a
counterbore. In the application, when the battery is produced,
electrolyte is injected into the battery through the
liquid injection hole, and then the sealing nail is assembled in the liquid injection hole for sealing. When secondary liquid injection,
exhaust gas discharge and negative pressure charging and discharging need to be performed subsequently, the sealing nail is pierced at the
counterbore for operation. The
counterbore can reduce the thickness of the sealing nail at the position, and is more easily pierced. The application enables the battery to be conveniently and quickly subjected to secondary liquid injection,
exhaust gas discharge and negative pressure charging and discharging, so that the battery can be used multiple times, the operation difficulty is low, and the operation efficiency is high. The position for secondary liquid injection,
exhaust gas discharge and negative pressure charging and discharging is the same as the operation position during production, the liquid
injection equipment and the tool fixture during battery production can be reused, various equipment and various parameters need not be adjusted, and production resource waste is avoided.