Easily Obtaining Excellent Performance High‐voltage LiCoO<sub>2</sub> via Pr<sub>6</sub>O<sub>11</sub> Modification
Yongcong Huang, Chenjie Xu, Jingguo Gao, Liao Shen, Qian Liu, Guiying Zhao, Qingshui Xie, Yingbin Lin, Jiaxin Li, Zhigao Huang
Abstract
Developing an effective method to synthesize high‐performance high‐voltage LiCoO 2 is essential for its industrialization in lithium batteries (LIBs). This work proposes a simple mass‐produced strategy for the first time, that is, negative temperature coefficient thermosensitive Pr 6 O 11 nanoparticles are uniformly modified on LiCoO 2 to prepare LiCoO 2 @Pr 6 O 11 (LCO@PrO) via a liquid‐phase mixing combined with annealing method. Tested at 274 mA g −1 , the modified LCO@PrO electrodes deliver excellent 4.5 V high‐voltage cycling performance with capacity retention ratios of 90.8% and 80.5% at 25 and 60 °C, being much larger than those of 22.8% and 63.2% for bare LCO electrodes. Several effective strategies were used to clearly unveil the performance enhancement mechanism induced by Pr 6 O 11 modification. It is discovered that Pr 6 O 11 can improve interface compatibility, exhibit improved conductivity at elevated temperature, thus enhance the Li + diffusion kinetics, and suppress the phase transformation of LCO and its resulting mechanical stresses. The 450 mAh LCO@PrO‖graphite pouch cells show excellent LIB performance and improved thermal safety characteristics. Importantly, the energy density of such pouch cell was increased even by ~42% at 5 C. This extremely convenient technology is feasible for producing high‐energy density LIBs with negligible cost increase, undoubtedly providing important academic inspiration for industrialization.