In-situ polymerization of hydroquinone-formaldehyde resin to construct 3D porous composite LiFePO4/carbon for remarkable performance of lithium-ion batteries

Abstract

A 3D porous composite LiFePO4/carbon material (LFP/RE) is synthesized via a facile method of the in-situ polymerization of hydroquinone-formaldehyde resin accompanying with the precursor co-precipitation and the subsequent carbothermal reduction process. Such 3D porous LFP/RE exhibits high specific surface area of 92.75 m2 g−1 and high pore volume of 0.1456 cm3 g−1, which can effectively improve the lithium ion diffusion coefficient up to 1.07 × 10−12 cm2 s−1. At 0.1 C, the LFP/RE displays a splendid discharge capacity of 169.3 mAh g−1 approximating to the theoretical specific capacity of LiFePO4. More importantly, when the rate increases to 20 C, the discharge capacity can still deliver to 105.8 mAh g−1 with an exceptionally outstanding retention of 93.8% after 500 charge-discharge cycles. It is illustrated that the superior interconnected porous structure of LFP/RE can provide fast-speed electronic transferred super highway, which greatly augments the cycle and rate performances of lithium-ion batteries.