The Synergistic Effect of Gd Modification on Improving the Electrochemical Performance of LiNi0.88Co0.09Al0.03O2 Cathode Materials

Abstract

Ni-rich cathode materials in the field of Li-ion batteries have been facing problems, such as poor cycle life and unstable crystal structure, which continue to baffle researchers. Herein, because of the extraordinary electric and magnetic properties of Gd, the dual Gd-modified Ni-rich cathode material LiNi0.88Co0.09Al0.03O2 (NCA) was successfully prepared in a high temperature solid-state method. As a result, the synergistic modification facilitates the migration of Li+ and protects the structure of electrode material. The dual Gd-modified NCA material exhibits capacity of 176 mAh·g−1 with retention reaching 89.3% at 1 C over 3.0–4.3 V at 25 °C after 100 cycles, whereas the pristine NCA material only delivers 151 mAh·g−1 with the retention of 77.0%. Otherwise, the capacity retention at 8 C as well as 55 °C improved sharply to over 80%. The significant improvement of rate and high temperature performance are attributed to the dual modification of Gd. This study will provide a new idea for the modification of Ni-rich layered cathode materials.