Enhanced electrochemical and storage properties of La2/3−XLi3XTiO3-coated Li[Ni0.4Co0.3Mn0.3]O2

A Li[Ni0.4Co0.3Mn0.3]O2 cathode was modified by applying a La2/3−XLi3XTiO3 (LLT) coating. Transmission electron microscope (TEM) images reveal that the coating layer consists of nanoparticles. The coated cathode demonstrated an enhanced rate capability, discharge capacity, and cyclic performance than the uncoated cathode. However, the influence of the coating upon these electrochemical properties is highly dependent upon the composition of the LLT coating layer. Coating layers having high La and low Li contents, such as La0.67TiO3, effectively improved the rate capability of the cathode. However, coating layers with a low La and high Li content greatly enhanced the discharge capacity of the cathode under high cut-off voltage (4.8 V) conditions. Overall, the thermal stability of the Li[Ni0.4Co0.3Mn0.3]O2 electrode was improved by the LLT coating. Storage tests confirmed that the La2/3−XLi3XTiO3 coating dramatically suppressed the dissolution of transition metals into the electrolyte.

► La2/3−XLi3XTiO3 (LLT) coated Li[Ni0.4Co0.3Mn0.3]O2 cathode.
► The effect of the coating was dependent upon the composition of the La2/3−XLi3XTiO3 coating layer.
► The La2/3−XLi3XTiO3 coating suppressed the dissolution of the transition metals into the electrolyte.