The design of a high-energy Li-ion battery using germanium-based anode and LiCoO2 cathode

Abstract

High capacity electrodes based on Ge composite anode and commercial LiCoO2 cathode, are evaluated and combined to fabricate a high energy lithium ion battery. The Ge composite anode, Ge/CHNs (Ge/carbon hybrid nanoparticles), is prepared with a co-precipitation followed by pyrolysis process, delivering a capacity of >1000 mA h g−1 over 2000 cycles. While for full cell assembling, galvanostatic cycling in lithium half-cells has been applied for prelithiating Ge/CHNs anodes to eliminate the first cycle irreversible capacity loss. Such process is shown to enable capacity matching between Ge/CHNs anodes and LiCoO2 cathodes, further influence the working voltage and cycle stability of the full cells. Finally, the lithium ion battery system based on the prelithiated Ge/CHNs anode and LiCoO2 cathode demonstrates a high energy density of 370 Wh kg−1 after 300 cycles between 2.7 and 4.4 V at 1C (the energy density here is based on the total weight of Ge/CHNs and LiCoO2), with average capacity fading about 0.018% per cycle. Thus, the designed battery system is promising candidate for energy storage applications with demand of high energy density and long cycle life.