Surface Modification of LiSr_(0.002)Ni_(0.9)Co_(0.1)O_2 by Overcoating with a Magnesium Oxide

摘要

Commercially obtained LiSr_(0.002)Ni_(0.9)Co_(0.1)O_2 was modified by overcoating its surface with MgO. As the surface was modified, onset temperature of thermal dissociation was increased about 10 ℃, and heat dissipation during thermal decomposition was diminished to a substantial extent. Lithium-ion batteries whose cathodes were made from the surface-modified LiSr_(0.002)Ni_(0.9)Co_(0.1)O_2 exhibited improved performance, especially at the demanding rate of 1 C. Tendency toward explosion in the cylindrical battery was largely alleviated by the surface treatment, even though the safety rating has not yet reached the industrial criterion.