Patent ID: 7195840

Claim:
An electrochemical device, comprising: (a) an electrode assembly comprising: i) an elongated positive electrode with a first longitudinal edge and a second longitudinal edge; ii) an elongated negative electrode with a first longitudinal edge and a second longitudinal edge; and iii) a separation layer having a first longitudinal edge and a second longitudinal edge and having a generally zig-zag shape; (b) a disc-shaped housing having a positive terminal electrically coupled to the first longitudinal edge of the positive electrode and a negative terminal electrically coupled to the first longitudinal edge of the negative electrode, wherein the electrode assembly is enclosed by the housing, the housing including a first cup having the positive terminal, a second cup including the negative terminal, the first cup and the second cup being joined together to form the housing such that the first and second cups are electrically isolated from one another and further wherein the positive terminal and negative terminal are generally planar. (c) an electrolyte adjacent to the electrode assembly and enclosed within the housing, the disc-shaped electrode assembly, the disc-shaped housing, and the electrolyte form a cell, wherein the second longitudinal edge of the positive electrode and the second longitudinal edge of the negative electrode reside within successive folds of the separation layer respectively and further wherein the positive electrode, the separation layer, and the negative electrode are wound around a central axis thereby forming a coil of alternating electrode and separation layers such that the separation layer prevents direct contact between successive electrode layers, the first longitudinal edge of the positive electrode extends beyond the first longitudinal edge of the separation layer, and the first longitudinal edge of the negative electrode extends beyond the second longitudinal edge of the separation layer.