Study on technology and mechanism of prelithiation for high-performance lithium iron phosphate battery
In this work,Li2NiO2(LNO)is employed as a cathode prelithiation additive for lithium iron phosphate(LFP)cathodes,paired with a high-capacity graphite-doped silicon oxide anode,to investigate the effects and mechanisms of prelithiation technology on LFP batteries.The electrochemical performance,structural composition,and surface morphology of LNO were meticulously evaluated,revealing that LNO possesses an irreversible capacity of 212.1 mAh/g,primarily comprising active Li0.63Ni1.02O2 postdelithiation.Subsequently,a 32 Ah pouch cell was fabricated by integrating 3%LNO into the cathode slurry,leading to a notable enhancement in the performance of the LFP batteries.Compared to the control group,the energy density and cycle life of the LFP batteries with LNO were increased by 4.9%and 50%,respectively.Moreover,the contribution of prelithiation technology to cycle stability was elucidated using a three-electrode method,revealing that an excessive quantity of cathode prelithiation additive could lead to the retention of active lithium ions on the anode.These ions are gradually released during cycling,ensuring a sustained replenishment of active lithium ions,thereby augmenting the cycle life of lithium-ion batteries.This study advances the application of cathode prelithiation technology in energy storage systems,providing both theoretical and experimental insights for the design and development of high-performance LFP batteries and facilitating the large-scale adoption of silicon-based anode materials.
lithium iron phosphate batterycathode prelithiation additivesilicon-based anodeenergy densitycycle life