3D lithiophilic framework with bimetallic phosphates to improve lithium deposition

Abstract

Bimetallic phosphides, Cu3P and Ni2P, were decorated on nickel foam to fabricate 3D lithiophilic framework by electrodeposition method and subsequent phosphating reaction. The electrodeposition time affected the uniformity of the Cu coating, then influenced the distribution of bimetallic phosphides. The half cell using the Cu3P-Ni2P@Ni (CNPNF-300) framework as an anode achieved 98.6 % Coulombic efficiency and 270 cycles under cycle capacity of 1 mAh cm−2 and current density of 1 mA cm−2. The performance of half cell confirmed that the optimal plating time was 300 s. The symmetrical cell fabricated with Li/LCNPNF (Li-Cu3P-Ni2P@Ni foam) showed remarkable cycling stability for 1800 h at 5 mA cm−2 with Li amount of 5 mAh cm−2. The excellent performance was attributed to favourable lithiophilic property, uniform local current density, and inhibition volume expansion of the LCNPNF hybrid framework electrode. Finally, a full battery combined with LiFePO4 as cathode and LCNPNF as anode exhibited the potential for practical applications with superior cycling stability (400 cycles at 0.5 C) and good rate performance.