Patent ID: 8557417

Claim:
A secondary battery comprising: a case comprising a body having a cavity and a cover sealed to the body; and an electrode assembly in the cavity, the electrode assembly comprising: a first electrode plate comprising a first electrode collector having a coated portion coated with a first active material and an uncoated portion not coated with the first active material; a second electrode plate comprising a second electrode collector having a coated portion coated with a second active material; and a separator between the first electrode plate and the second electrode plate, wherein the first electrode plate, the second electrode plate and the separator are stacked together, wherein the first electrode collector and the second electrode collector have substantially the same surface area, wherein the surface area of the coated portion of the second electrode plate is larger than the surface area of the coated portion of the first electrode plate, and wherein the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate.