| 摘要 |
PROBLEM TO BE SOLVED: To stabilize welding capability of resistance welding of a current collecting tab to a positive electrode plate and a sealing plate, and provide a battery having the current collecting tab capable of realizing high welding reliability in the positive electrode plate and the sealing plate by specifying the surface roughness of the current collecting tab of the battery. SOLUTION: A current collecting tab 2 used for this battery has a surface roughness of 0.1-4 μm, and can use the conventional material. The specified surface roughness is formed on the whole surfaces of both sides of the current collecting tab 2 or on only the one side. Only the portion for being welded to a current collecting substrate or a sealing plate may be formed so as to have the specified surface roughness. If the surface roughness is smaller than 0.1 μm, the surface state becomes a smooth surface similar to a bright finishing surface, the contact resistance with a mix non-coating part of the current collecting substrate or the sealing plate is decreased, the generation of Joule heat is decreased, and usable nugget formation is made difficult. |
