Hard carbon anode derived from camellia seed shell with superior cycling performance for sodium-ion batteries

Hard carbons are deemed as the promising anodes for commercialized sodium-ion batteries owing to their abundant resources, low cost, and low-plateau potential (~0.1 V vs. Na+/Na). However, the practical application of hard carbon anodes has been hindered by their unstable long-time cycling performance. Herein, hard carbon anode derived from camellia (TS1300) seed shell exhibits a high reversible capacity of 299.1 mA h g-1 together with a superior stable capacity retention of 93.8% over 1000 cycles. Further experimental results reveal that the proper graphene interlayer spacing (0.375 nm) and graphitic-like nanodomain structure are critical to the excellent electrochemical performance. Therefore, this hard carbon material derived from camellia seed shell is a promising anode for high-performance sodium-ion batteries.