Cathode material for high energy lithium batteries - improvement on 4V-class cathode, LiNiO₂

LiNiO₂ is investigated as a cathode material for secondary lithium batteries. Almost all the samples have lithium defects in the structure because of the high volatility of lithium salt. The defects are substituted by excess nickel, which disturbs the lithium diffusion, thus decreasing the discharge capacity. A sample with an ideal chemical composition shows a discharge capacity of over 200 mAh/g with an average voltage of 3.8V, showing a 30% increase of energy density over known cathode LiCoO₂. The cathode can also be used for lithium-ion batteries.