EXPLOSION-PROOF SHEET OF SECONDARY BATTERY AND SECONDARY BATTERY

An explosion-proof sheet of a secondary battery and a secondary battery are provided. The explosion-proof sheet has a main body portion, a fixing portion, and a cracking portion. The main body portion is opposite to the explosion-proof hole. A strengthening region is formed on the main body portion. The fixing portion is disposed around the main body portion, and the fixing portion is connected to a periphery of the explosion-proof hole. The cracking portion is located between the fixing portion and the main body portion and connected to the fixing portion and the main body portion.