Related Experiment Video
Updated: May 12, 2026
Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery
Published on: July 12, 2016
Designing Multifunctional Catalysts for Lithium-Oxygen Batteries via an Amine-Epoxide Ring-Opening Reaction
Wei Li1, Yan Ma2, Chuanchao Sheng1
1Center of Energy Storage Materials & Technology, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, National Laboratory of Solid State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, P. R. China.
None:
Li-O2 batteries, with an impressive theoretical specific energy of 3600 Wh kg-1, face challenges such as low discharge capacity, high charging overpotential, instability caused by singlet oxygen, and the shuttle effect, where soluble catalysts migrate to the anode, leading to degradation and lithium loss. An optimal strategy would incorporate three types of soluble additives: a catalyst to increase the discharge capacity, a redox mediator to lower the charging overpotential, and a scavenger to neutralize singlet oxygen. However, combining multiple additives poses compatibility issues and does not fully address the shuttle effect. To tackle these issues, we propose a multifunctional long-chain catalyst molecule equipped with a superoxide scavenger, redox mediator, and quencher for singlet oxygen. The long-chain structure anchors the molecule, preventing it from diffusing to the anode. Following this strategy, we designed P-TEMPO-TPA by grafting 2,2,6,6-tetramethyl-1-piperoxyl (TEMPO) and triphenylamine (TPA) onto a long-chain backbone. This molecule promotes Li2O2 formation, increasing the discharge capacity by 35 times and reducing singlet oxygen-driven side reactions. The soluble long-chain catalyst lowers the charging voltage to 3.65 V, extending the cycle life to 350 cycles (0.3 mAh cm-2) and 100 cycles (1.2 mAh cm-2). The long-chain design effectively mitigates the shuttle effect, paving the way for high-performance Li-O2 batteries.
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