Homogeneous regeneration of spent LiFePO 4 via in situ Al/F impurity introduction: tailoring Li–Fe anti-sites for great cycling stability

Trace Al/F co-doping in spent LiFePO 4 regulates antisite defects, reduces charge-transfer resistance and accelerates Li + diffusion. The regenerated cathode delivers 141.78 mAh g −1 at 1.0C and retains over 90% capacity after 500 cycles.