Preparation and Performance of Regenerated Al 2 O 3 -Coated Cathode Material LiNi 0.8 Co 0.15 Al 0.05 O 2 from Spent Power Lithium-Ion Batteries.

In this study, LiNiCoAlO@x%AlOcoated cathode materials were regeneratively compounded by the solid-phase sintering method, and their structural characterization and electrochemical performance were systematically analyzed. The regenerated ternary cathode material precursor synthesized by the co-precipitation method was roasted with lithium carbonate at a molar ratio of 1:1.1, and then completely mixed with different contents of aluminum hydroxide. The combined materials were then sintered at 800 °C for 15 h to obtain the regenerated coated cathode material, LiNiCoAlO@x%AlO. The thermogravimetry analysis, phase composition, morphological characteristics, and other tests show that when the added content of aluminum hydroxide is 3%, the regenerated cathode material, LiNiCoAlO@1.5%AlO exhibits the highest-order layered structure with AlO coating. This material can better inhibit the production of Ni, and improve material structure and electrochemical properties. The first charge-discharge efficiency of the battery assembled with this regenerated cathode material is 97.4%, a 50-cycle capacity retention is 93.4%, and a 100-cycle capacity retention is 87.6%. The first charge-discharge efficiency is far better than that of the uncoated regenerated battery.