Li2−xFe1−xAlxSiO4/C Nanocomposites Cathodes for Lithium‐Ion Batteries

Recently, Li2FeSiO4 has been identified as one of the most attractive cathode materials for lithium‐ion batteries because it has the ability to exchange more than one Li+ per redox‐active transition‐metal ion. However, this material behavior has been difficult to realize at room temperature due to the redox reaction of Fe3+/Fe4+. In this article, Li2−xFe1−xAlxSiO4/C (x=0, 0.01, 0.03, 0.05, 0.08, 0.12, and 1) nanocomposites were synthesized by using a facile sol–gel method and shown to exhibit much improved electrochemical performance at room temperature. It was found that after doping, two charge–discharge potential plateaus could be clearly obtained. In particular, the examined system, Li1.97Fe0.97Al0.03SiO4/C showed the best electrochemical performance with 209.3 mAh g−1 at 0.2 C, corresponding to a release of 1.26 Li+ per molecule. An ode to cathodes: Recently, Li2FeSiO4 has been identified as one of the most attractive cathode materials for lithium‐ion batteries because it has the ability to exchange more than one Li+ per redox‐active transition‐metal ion. In this article, Li2−xFe1−xAlxSiO4/C nanocomposites are synthesized by using a facile sol–gel method and shown to exhibit much improved electrochemical performance at room temperature.