UNIFORM STABILIZATION NANOCOATINGS FOR LITHIUM RICH COMPLEX METAL OXIDES AND ATOMIC LAYER DEPOSITION FOR FORMING THE COATING

摘要

Stabilization coating that are uniform and penetrating have been found to provide desirable stabilization coatings for lithium rich metal oxide cathode active materials. In particular, the uniform and penetrating coatings can be particularly desirable for improving storage stability of batteries formed with the active material. The stabilization coatings can be inert metal oxides, such as aluminum oxide. The uniform and penetrating stabilization coatings can be formed using atomic layer deposition. The coatings can further effectively stabilize cycling of the batteries, and batteries formed with the stabilization coating can exhibit modest increases in DC electrical resistance.

主权项

1. A battery comprising a positive electrode comprising a cathode active material and a negative electrode comprising graphitic carbon, wherein the cathode active material comprises a lithium rich metal oxide approximately represented by the formula Li1+cM1−dO2, where c≧0, d is from about c−0.2 to about c+0.2 with the proviso that d≧0 and a uniform and up to about 5 mole percent of the oxygen can be replaced with a fluorine dopant and a penetrating stabilization coating having an average thickness of no more than about 5 nm, and wherein the battery maintains at least about 85% capacity following 12 weeks of storage at 45° C. at 4.35V.