Patent ID: 8257861

Claim:
A sealed battery comprising: an electrode assembly having stacked multiple positive electrode substrates exposed at one end and stacked multiple negative electrode substrates exposed at the other end; a positive collector connected to the positive electrode substrates; a negative collector connected to the negative electrode substrates; wherein the positive collector and a positive collector receiving part are resistance-welded across the stacked multiple positive electrode substrates, and/or the negative collector and a negative collector receiving part are resistance-welded across the multiple negative electrode substrates, by carrying out a resistance-welding process; wherein a groove is formed around a resistance-welded portion of at least any one of the positive collector, the positive collector receiving part, the negative collector and the negative collector receiving part, and wherein the groove is formed in a region opposing to an outermost surface of the stacked multiple positive electrode substrates and/or the stacked multiple negative electrode substrates, wherein the groove has a bottom.