Abstract
A green process route to recycle LiFePO<inf>4</inf>/C electrode materials is proposed in this work. First, a robust strategy to synthesize LiFePO<inf>4</inf>/C cathode materials from a precursor of a crystalline FePO<inf>4</inf>·2H<inf>2</inf>O phase (metastrengite I) is presented. In order to prepare crystalline FePO<inf>4</inf>·2H<inf>2</inf>O, a solution precipitation route is adapted, where the reaction conditions such as temperature and pH are precisely controlled. Among various heat treatment temperatures to calcine our prepared FePO<inf>4</inf>·2H<inf>2</inf>O with lithium sources, we find that LiFePO<inf>4</inf>/C cathode materials synthesized at 700°C deliver a maximum discharge capacity of 168.51 mA h g<sup>-1</sup> at 0.1 C (1 C rate = 170 mA h g<sup>-1</sup>) with a capacity retention of 99.36% after the 25<sup>th</sup> cycle at 1 C. Furthermore, commercially available LiFePO<inf>4</inf> powders and recovered LiFePO<inf>4</inf> electrode materials from spent batteries are both tested with our developed recycling process, where we decompose LiFePO<inf>4</inf> powders/electrodes to prepare crystalline FePO<inf>4</inf>·2H<inf>2</inf>O, and then re-synthesize LiFePO<inf>4</inf>/C cathode materials. In both cases, our recycled LiFePO<inf>4</inf>/C exhibits a very comparable discharge capacity of ∼140 mA h g<sup>-1</sup> at 1 C with a capacity retention of ∼99%.
| Original language | English |
|---|---|
| Pages (from-to) | 11493-11502 |
| Number of pages | 10 |
| Journal | Journal of Materials Chemistry A |
| Volume | 3 |
| Issue number | 21 |
| DOIs | |
| Publication status | Published - 2015 Jun 7 |
ASJC Scopus subject areas
- Chemistry(all)
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)
