Abstract: A battery end plate assembly includes an end plate and a side plate. The end plate is provided with a connecting groove on a side for connecting the side plate. An end of the side plate is embedded in the connecting groove and abuts against a side wall of the connecting groove.

Abstract: A laser welding copper nozzle, a laser welding auxiliary apparatus and a laser welding device are provided. In some embodiments, the laser welding copper nozzle includes: a gas intake port configured to be in communication with a gas intake channel, so as to enable a blowing device to blow a gas to the gas intake port through the gas intake channel during laser welding; and a gas exhaust port configured to be in communication with a gas extraction channel, so as to enable a gas suction device to extract the gas from the gas exhaust port through the gas extraction channel during the laser welding. An axis of the gas intake port and an axis of the gas exhaust port are in the same straight line, and a laser channel for allowing laser to pass during the laser welding is formed between the gas intake port and the gas exhaust port.