主题：【原创】艰难的一跃 -- 晨枫

Batteries are thought of as having high energy density but low power rates, while for fast-discharging supercapacitors the opposite is true. Byoungwoo Kang and Gerbrand Ceder have now developed a lithium-ion battery that challenges that assumption, discharging extremely rapidly and maintaining a power density similar to a supercapacitor, two orders of magnitude higher than a normal lithium-ion battery. This is achieved by modifying LiFePO4, a material widely used in batteries. The starting point is nanosized LiFePO4, which already gives relatively fast discharge rates, which is then coated with a similar compound that is slightly Fe,P,O-deficient. On heating, the coating forms a glassy top layer that enhances lithium-ion mobility. The performance of batteries based on this technology could lead to new applications for electrochemical energy storage.