摘要

A high-energy full concentration-gradient cathode material with an average composition of Li(Ni0.8Co0.1-Mn0.1)O-2 has been successfully synthesized by a hydroxide co-precipitation method. Ni content decreases gradually along the radius of the spherical particle, and the content of Co and Mn increases. The electrochemical properties of this concentration-gradient material are studied and compared to those of the homogeneous Li(Ni0.8Co0.1Mn0.1)O-2 material. In the concentration-gradient material of Li(Ni0.8Co0.1Mn0.1)O-2, the inside part rich in Ni delivers a very high capacity, while the Mn-rich outside part improves the cycling stability and rate performance. The concentration-gradient material has superior electrochemical properties compared to the homogeneous material. The initial capacity of the concentration-gradient Li(Ni0.8Co0.01Mn0.1)O-2 is 185.2 mA h g(-1) at I C between 2.8 and 4.3 V and retains 93.2% after 100 cycles. The composite also has a good rate performance with a high capacity of about 175 mA h g(-1) even at 2 C rate.