Patent attributes
A rechargeable lithium ion button cell battery having a sealed housing comprises an inner casing and an outer casing, both casings have at least one flat area as top or bottom of the battery, and a round or oval sidewall vertically formed to the flat area. An insulation gasket is positioned between the sidewalls, and the outer casing opening is mechanically crimped to complete the seal of the battery. Inside the sealed housing the anode and cathode electrodes are spiral wound with separator to be a round or oval roll. A roll axis is vertical to the flat area of the casings. The two electrodes are tapered in width to fully utilize the inner space. The electrodes comprise current collectors of metal foils coated with lithium-intercalating active materials, leaving small area of uncoated metal foils as conductor tabs for connecting the electrodes to the casings.
