Haojie Hu, Xiaonan Wei, Junfei Ding, Shucheng Liu, Yanli Chen, Xiaosi Qi, Qiong Peng
Mechanical stress from Li2CO3 accumulation severely limits Li-CO2 battery life. We report that the strengthened negative Poisson's ratio (NPR) in flexible Cu-regulated Ti2B2 enables stable and durable catalytic Li2CO3 formation/decomposition. Under ±3% strain, CO2 redox overpotential fluctuates by merely 0.09 V. This strain resistance in NPR materials provides an intriguing insight into resolving volume expansion and sluggish kinetics in metal-air batteries.