New facile synthesis route for obtaining phase pure LiFePO4/C composite

Abstract

Carbon-coated, olivine-structured LiFePO4 suitable for cathode material in rechargeable lithium batteries has been prepared via simple, both time and energy low-consuming synthesis route. Procedure involves soaking of cellulose-containing substrate with aqueous precursor solution followed by rapid (several minutes long) single heating step. Cellulose acts as (i) reducing agent and (ii) carbon source which suppresses growth and prevents agglomeration of LiFePO4 particles and also creates a conductive network in LiFePO4/C composite. The crystalline structure, morphology and charge/discharge performance of the as-prepared composite were investigated by means of XRD analysis, electron microscopy and galvanostatic charge-discharge tests. LiFePO4/C powder appears to be nanocrystalline (with mean crystallite size of 37 nm) and electrochemically stable achieving 97% (165 mAhg-1) of its theoretical capacity.