CATHODE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, METHOD OF PRODUCING THE SAME, AND LITHIUM ION SECONDARY BATTERY

摘要

The present invention discloses a cathode material for lithium ion secondary battery. The cathode material is in the form of powder particles. The powder particle includes a bulk portion and a coating portion coated on the outer surface of the bulk portion. The bulk portion is formed of at least one first cathode material which is a lithium-nickel based composite oxide. The first cathode material has electrochemical activity and has high charging-discharging specific capacity at a charged voltage of 4.2V versus Li/Li+. The coating portion is formed of at least one second cathode material. The second cathode material has no electrochemical activity or has low charging-discharging specific capacity at a charged voltage of 4.2V versus Li/Li+. Lithium ion secondary battery using the cathode material has high energy density, cycling stability, security, and output power.

主权项

1. A cathode material for a lithium ion secondary battery, wherein the cathode material is in the form of powder particles, the powder particle includes a bulk portion and a coating portion coated on the outer surface of the bulk portion, the bulk portion is formed of at least one first cathode material which is a lithium-nickel based composite oxide, the first cathode material has electrochemical activity and has high charging-discharging specific capacity at a charged voltage of 4.2V versus Li/Li+, the coating portion is formed of at least one second cathode material, the second cathode material has no electrochemical activity or has low charging-discharging specific capacity at a charged voltage of 4.2V versus Li/Li+.