Polypyrrole-coated triple-layer yolkshell Fe2O3 anode materials with their superior overall performance in lithium-ion batteries

Iron oxide (Fe2O3) emerges as a highly attractive anode candidate among rapidly expanding energy storage market. Nonetheless, its considerable volume changes during cycling as an electrode material result in a vast reduced battery cycle life. We pioneer an approach for preparing high-performance Fe2O3 anode materials, by innovatively synthesizing a triple-layer yolkshell Fe2O3 uniformly coated with a conductive polypyrrole layer (Fe2O3@Ppy-TLY). The uniform polypyrrole coating enhances the material's electrical conductivity and maintains structure stability through charge/discharge process. In the uses as lithium-ion battery electrodes, Fe2O3@Ppy-TLY demonstrates high reversible specific capacity (maintaining a discharge capacity of 1375.11 mAh·g-1 after 500 cycles at 1 C), exceptional cycling stability (retaining the steady charge-discharge performance at 544.33 mAh·g-1 after 6000 ultrafast charge/discharge cycles at a 10 C current density), and outstanding high current charge-discharge performance (retaining a reversible capacity of 156.75 mAh·g-1 after 10000 cycles at 15 C), thereby exhibiting superior lithium storage performance. This study introduces innovative advancements for Fe2O3 anode design, aiming to enhance its performance in energy storage fields.