An Organic Anode for High Temperature Potassium-Ion Batteries

The wide applications of rechargeable batteries require state-of-the-art batteries that are sustainable (abundant resource), tolerant to high-temperature operations, and excellent in delivering high capacity and long-term cycling life. Due to the scarcity and uneven distribution of lithium, it is urgent to develop alternative rechargeable batteries. Herein, an organic compound, azobenzene-4,4'-dicarboxylic acid potassium salts (ADAPTS) is developed, with an azo group as the redox center for high performance potassium-ion batteries (KIBs). The extended pi-conjugated structure in ADAPTS and surface reactions between ADAPTS and K-ions enable the stable charge/discharge of K-ion batteries even at high temperatures up to 60 degrees C. When operated at 50 degrees C, ADAPTS anode delivers a reversible capacity of 109 mAh g(-1) at 1C for 400 cycles. A reversible capacity of 77 mAh g(-1) is retained at 2C for 1000 cycles. At 60 degrees C, the ADAPTS-based KIBs deliver a high capacity of 113 mAh g(-1) with 81% capacity retention at 2C after 80 cycles. The exceptional electrochemical performance demonstrates that ADAPTS is a promising electrode material for high-temperature KIBs.