Battery cover and battery

The utility model relates to the technical field of batteries, and discloses a battery cover and a battery, a top cover of the battery cover is provided with a first through hole in a penetrating manner, an insulating support is arranged below the top cover and is provided with a second through hole opposite to the first through hole in a penetrating manner, and a pole piece is arranged above the top cover and comprises an annular part and a boss part, the boss part is arranged in an inner hole of the annular part, one end of the boss part is connected to the inner wall face of one side of the annular part and extends towards the inner wall of the other side of the annular part, a window formed between the other end of the boss part and the inner wall face of the other side of the annular part is communicated with the first through hole, and the pole cover covers the inner hole of the annular part. And the tab positioned in the shell can sequentially penetrate through the second through hole, the first throug