Preparation and electrochemical performance of La2O3 coated LiNi0.8Co0.1Mn0.1O2 material

High nickel ternary materials have high electrochemical activity. But because of the side reactions with the electrolyte and irreversibly dissolve the transition metal ions, nickel ternary materials are difficult to carry out the dissociation and intercalation reaction during the charge and discharge reaction of the battery. In present work, lanthanum oxide coated on the surface of high nickel ternary materials was successfully prepared by using the liquid phase atomic deposition method. And the compound material was characterized by SEM and TEM. The tests results showed that the lanthanum oxide coating did not change the crystal structure of the raw materials. The coating layer could effectively improve the electrochemical stability of the high nickel ternary material. The first discharge capacity of the 4 wt. % La2O3 coated material at 1 C rate is 177.2mAh center dot g-1, which was close to that of the uncoated material 179.2mAh center dot g-1. However, the capacity still maintained 150.9mAh center dot g-1 and retention rate of the coating material is 85.2 % when that of the uncoated material was only 121.0mAh center dot g-1 after 100 cycles. In addition, the AC impedance test also showed that the lanthanum oxide coating layer could effectively improve the surface stability of the high nickel ternary material.