Most batteries for Bluetooth headset are a rectangular shape, which capacity is 200 to 500mAh range, but they do not make use of the entire space of the Bluetooth headset they power, because most Bluetooth headsets are the round shape or oval shape. The customized shaped batteries created by Grepow can better fit into the remaining spaces of the Bluetooth headsets, and provide maximum capacity. Furthermore, Grepow provides solutions for high discharge rates and high voltage cells. Customers need only focus on the design of their product, Grepow will provide the maximum capacity solution.