Panasonic showed off a new li-ion battery technology that uses silicon alloy anodes. The new design enables a capacity of 4.0Ah, about 30 percent more than the firm's prior design with a graphite anode. The new batteries are expected to be available in the company's fiscal 2012.
Panasonic improved fabrication techniques and made other modifications to reduce the characteristic deterioration caused by this volumetric change. The concrete improvements have not been disclosed, but the firm claims that even after 500 charge/discharge cycles at least 80% capacity is retained.
The initial target application will be notebook PCs, but a source at the firm comments "the ultimate target is vehicles." For vehicular applications, weight will be a key issue. The current design weighs about 54g per cell, which is about 10g more than the company's prior model (NCR18650A). The weight energy density is about 252Wh/kg, or about the same as existing graphite designs, indicating that the full potential of Si has yet to be attained.