Ultrahigh Capacity Retention of Li 2 ZrO 3 -Coated Ni-rich LNCM811 Cathode Material through Covalent Interfacial Engineering

Nickel-rich LiNi 0.8 Co 0.1 Mn 0.1 O 2 (LNCM811) is a promising lithium-ion battery cathode material, whereas the surface-sensitive issues (i.e., side reaction and oxygen loss) occurring on LNCM811 particles significantly degrade their electrochemical capacity retentions. A uniform Li 2 ZrO 3 coating layer can effectively mitigate the problem by preventing these issues. Instead of the normally used weak hydrogen-bonding interaction, we present a covalent interfacial engineering for the uniform Li 2 ZrO 3 coating on LiNi 0.8 Co 0.1 Mn 0.1 O 2 materials. Results indicate that the strong covalent interactions between citric acid and Ni 0.8 Co 0.1 Mn 0.1 (OH) 2 precursor effectively promote the adsorption of ZrO 2 coating species on Ni 0.8 Co 0.1 Mn 0.1 (OH) 2 precursor, which is eventually converted to uniform Li 2 ZrO 3 coating layers of about 7 nm after thermal annealing. The uniform Li 2 ZrO 3 coating endows LNCM811 cathode materials with an exceptionally high capacity retention of 98.7% after 300 cycles at 1 C. This work shows the great potential of covalent interfacial engineering for improving the electrochemical cycling capability of Ni-rich lithium-ion battery cathode materials.