Apple‐Biowaste‐Derived Hard Carbon as a Powerful Anode Material for Na‐Ion Batteries

Abstract Modern industrial agriculture is strongly influenced by product norms and standards, resulting in massive amounts of fresh fruit that is left in the field or wasted in spite of their good nutritional value. Herein, we present the synthesis of hard carbon from natural apple biowaste, and its use of biomass is a suitable strategy for the development of cheap and powerful carbon‐based active materials for Na‐ion batteries. The hard carbon exhibits a good rate capability [112 mAh g −1 at 5 C (1 A g −1 )], excellent long‐term cycling stability (1000 cycles at 5 C), and high specific capacity (245 mAh g −1 at 0.1 C) with full retention after 80 cycles. The full capacity (250 mAh g −1 ) of the hard carbon is also obtained in Na‐ion cells by using the layered P2‐type Na x Ni 0.22 Co 0.11 Mn 0.66 O 2 cathode. The good electrochemical performance as well as the low cost and environmental friendliness of the apple‐biowaste‐derived hard carbon proves its suitability for future Na‐ion batteries.