Study on novel functional materials carboxymethyl cellulose lithium (CMC-Li) improve high-performance lithium-ion battery

•Novel functional material CMC-Li is synthesized with cotton as raw material by a unique two-step method.•New nanometer fiber CMC-Li, CMC-Li/LFP, CLL models are obtained by electrospinning for the first time.•Novel unique method of modified electrode materials using CMC-Li are applied in lithium-ion battery for the first time.•The good electrochemical property using CMC-Li and new method for batteries is reported for the first time.•This novel functional material and new method can increase the contents of freely moving lithium ions and the efficiency.

Novel cellulose derivative CMC-Li was synthesized by cotton as raw material. The mechanism of the CMC-Li modified electrode materials by electrospinning was reported. CMC-Li/lithium iron phosphate (LiFePO4, LFP) composite fiber coated with LFP and CMC-Li nanofibers was successfully obtained by electrospinning. Then, CMC-Li/LFP nano-composite fiber was carbonized under nitrogen at a high temperature formed CNF/LFP/Li (CLL) composite nanofibers as cathode material. It can increase the contents of Li+, and improving the diffusion efficiency and specific capacity. The battery with CLL as cathode material retained close to 100% of initial reversible capacity after 200 cycles at 168 mAh g−1, which was nearly the theoretical specific capacity of LFP. The cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscope (SEM) were characterizing material performance. The batteries have good electrochemical property, outstanding pollution-free, excellent stability.