It is clear that the small capacity Li-ion (polymer) Battery containing lithium cobalt oxide (LiCoO2) offers a genuinely viable option for electronics and digital applications. However, lithium cobalt oxide (LiCoO2) is very expensive and un-safe for large capacity Li-ion Battery. Recently lithium iron phosphate (LiFePO4) has been becoming "best-choice" materials in commercial Li-ion (polymer) Batteries for large capacity and high power applications, such as lap-top, power tools, e-wheel chair, e-bike, e-car and e-bus. A LiFePO4 battery has hybrid characters: as safe as lead-acid battery and as powerful as lithium ion cells.