Patent ID: 7316863

Claim:
A battery pack housing a plurality of battery cells, the battery pack comprising: a case having a conductive terminal board respectively connecting positive electrodes and negative electrodes of said plurality of battery cells to outside terminals, wherein said conductive terminal board has a structure in which a first member is joined with a second member such that said first member having excellent weldability is arrayed in a plurality-of-islands state in said second member having excellent conductivity, the islands of the first member being formed as a common structure such that adjacent islands are connected by a narrow portion that is narrower than the respective island portions, wherein said first member of said conductive terminal board includes a rectangular slit in at least one island portion of the first member and the positive electrodes and the negative electrodes of said battery cells are welded to said first member of said conductive terminal board through resistance welding, and wherein said second member having excellent conductivity has a structure in which a projecting portion for connecting a control circuit substrate is provided on one short side of a plate portion having an oblong card shape that is larger than said first member in outer shape thereof, said first member being joined with said plate portion of said second member, a combined thickness of said first member joined with said second member being approximately uniform.