Recovery of lithium hydroxide monohydrate from a nickel-rich cathode material by a novel heat-treatment process at a significantly low temperature

Abstract

Lithium hydroxide monohydrate (LiOH·H2O) was easily recovered from LiNi[Formula: see text]Co[Formula: see text]Al[Formula: see text]O2, a Ni-rich cathode material, by a novel heat-treatment process, under a hydrogen (H2) atmosphere at a significantly low temperature of 500∘C. This process is eco-friendly and can facilitate the recovery of valuable metals without requiring acids. Because of the low O2 partial pressure (1.0 × 10[Formula: see text] atm) of the H2 atmosphere, the characteristic (003) X-ray diffraction peak of the layered cathode material disappeared at 500∘C, and LiOH·H2O was easily recovered. To the best of our knowledge, this is the lowest temperature ever employed for LiOH·H2O recovery from Ni-rich cathode materials using the dry method.