Study on the Performance of Nd 3+ /Br - Co-doped LiNi 1/3 Co 1/3 Mn 1/3 O 2 Cathode Materials Synthesized by Co-precipitation-Polymer Network Gel Method

Nd 3+ /Br - co-doped Li(Ni 1/3 Co 1/3 Mn 1/3 ) 0.98 Nd 0.02 O 1.9 Br 0.1 cathode material was successfully synthesized via the co-precipitation-polymer network gel method. The material demonstrated outstanding electrochemical performance, exhibiting superior rate capability and cycling stability: at 0.2C, it delivered a high initial specific discharge capacity of 207.1 mAh·g -1 ; at 0.5C, the initial discharge capacity reached 193.5 mAh·g -1 , with a capacity retention of 78.8% after 200 cycles. Moreover, the corresponding capacity retention rates were 79.8% and 70.5% after 100 cycles at 1C and 2C, respectively; even at a high current rate of 5C, a favorable capacity retention rate of 58.2% was still maintained after 100 cycles. The enhanced performance is attributed to the Nd 3+ /Br - co-doping, which induces expansion of the unit cell volume, thereby increasing the interplanar spacing and widening the Li + diffusion channels. Furthermore, this dual-doping strategy reduces the charge transfer resistance and electrochemical polarization of the cathode, while simultaneously enhancing the Li + diffusion kinetics.