Patent ID: 8993148
Filing Date: 2015-03-31
Classification: H01M,Y02E,Y02P

Abstract:
1. A rechargeable lithium ion button cell comprises: (a). a sealed housing comprising an inner casing and an outer casing, both casings having at least one flat area as top or bottom of the battery, and a round or oval side wall vertically formed to the flat area, said side walls are single wall not folded double walls; (b). said sealed housing also comprising a round or oval insulation gasket having a footing rim and positioning between said side walls, said footing rim covering the opening end of said inner casing side wall; (c). a first electrode and a second electrode inside the said sealed housing being spiral wound with separator to be a round or oval roll, said roll axis is vertical to the said flat areas of the casings; (d). said electrodes respectively has a small part of metal projected out of the main body of said electrodes acting as a welding tab; wherein a metal flake, which is separate from said outer casing and has exact the same shape of the inner flat area of said outer casing, is welded with said welding tab of the first electrode, and said metal flake is pushed by the inner flat area of said outer casing onto the opening end of said inner casing and pressed against said gasket footing rim, to have reliable contact to said outer casing and sealed inside the battery housing therewith; wherein said metal flake enables said welding tab of the first electrode having only one 90 degree turn from a direction of said roll axis at a point out of the main body of said spiral wound electrodes, to a direction of the flat area of the battery outer casing, to have its length to be least thereafter.