General and Green Strategy toward High Performance Positive Electrode Materials for Rechargeable Li Ion Batteries with Crop Stalks as the Host Carbon Matrixes

摘要

A novel, simple and universal approach toward the sheetlike carbon composites is presented here. In the method, an abundant agricultural byproduct (produced at a rate of 2.2 × 107 tons/year in China), obtained from the sustainable, environmentally friendly crop stalks, was used as a porous template for large-scale production of high performance cathode materials for lithium ion batteries. Owing to the large surface area, porous structure and small size of the functional particles, the nanocomposites manifest excellent electrochemical performance. Furthermore, the porous structure and charge transport property of the carbon materials can provide an electronic conductive network and promote the lithium ion extraction/insertion. In particular, the prepared LiFePO4/C composites present a high reversible capacity of 158 mAh g~(-1) after 500 cycles, indicating crop stalks can be a massive resource for high performance lithium ion batteries.