Technology Trends of Cathode Active Materials for Lithium Ion Battery

Abstract

With the increasing size and universalization of lithium-ion batteries, the development of cathode materials has emerged as a critical issue. The energy density of 18650 cylindrical batteries had more than doubled from 230 Wh/l in 1991 to 500 Wh/l in 2005. The energy capacity of most products ranges from 450 to 500 Wh/l or from 150 to 190 Wh/kg. Product developments are focusing on high capacity, safety, saved production cost, and long life. As Co is expensive among the cathode active materials LiCoO 2 , to increase energy capacity while decreasing the use of Co, composites such as LiMn 2 O 4 , LiCo 1/3 Ni 1/3 Mn 1/3 O 2 , LiNi 0.8 Co 0.15 Al 0.05 O 2, and LiFePO 4 -C (167 mA/g) are being developed. Furthermore, many studies are being conducted to improve the performance of battery materials to meet the requirement of large capacity output density such as 500Wh/kg for electric bicycles, 1,500 Wh/kg for electric tools, and 4,000~5,000 Wh/kg for EV and PHEV. As new cathodes active materials with high energy capacity such as graphene-sulfur composite cathode materials with 600 Ah/kg and the molecular cluster for secondary battery with 320 Ah/kg are being developed these days, their commercializations are highly anticipated.

Archives of Metallurgy and Materials

“…At present, lithium ion batteries (LIBs) are widely used as a main energy source for portable mobile devices such as smartphones and netbooks as well as hybrid vehicles due to high output and high energy characteristics. Lithium ion batteries, which are expected to be used extensively in electric vehicles (EV) and for electric power storage, are capable of storing and using energy through oxidation and reduction reactions that occur in the anode and the cathode [1].…”