State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
Key Laboratory of Automobile Materials, Ministry of Education, and Department of Materials Science and Engineering, Jilin University, Changchun, Jilin, China.
Nat Chem. 2019 Jan;11(1):64-70. doi: 10.1038/s41557-018-0166-9. Epub 2018 Nov 12.
Rechargeable aprotic alkali metal (Li or Na)-O batteries are the subject of great interest because of their high theoretical specific energy. However, the growth of dendrites and cracks at the Li or Na anode, as well as their corrosive oxidation lead to poor cycling stability and safety issues. Understanding the mechanism and improving Li/Na-ion plating and stripping electrochemistry are therefore essential to realizing their technological potential. Here, we report how the use of a Li-Na alloy anode and an electrolyte additive realizes an aprotic bimetal Li-Na alloy-O battery with improved cycling stability. Electrochemical investigations show that stripping and plating of Li and Na and the robust and flexible passivation film formed in situ (by 1,3-dioxolane additive reacting with the Li-Na alloy) suppress dendrite and buffer alloy anode volume expansion and thus prevent cracking, avoiding electrolyte consumption and ensuring high electron transport efficiency and continued electrochemical reactions.
可充式非质子碱金属（Li 或 Na）-O 电池因其具有高理论比能量而备受关注。然而，Li 或 Na 阳极的枝晶和裂纹生长以及腐蚀性氧化会导致较差的循环稳定性和安全问题。因此，了解机制并改善 Li/Na 离子的电镀和剥离电化学对于实现其技术潜力至关重要。在这里，我们报告了如何使用 Li-Na 合金阳极和电解质添加剂来实现具有改进循环稳定性的非质子双金属 Li-Na 合金-O 电池。电化学研究表明，Li 和 Na 的剥离和电镀以及原位形成的坚固灵活的钝化膜（通过 1,3-二氧戊环添加剂与 Li-Na 合金反应）抑制了枝晶并缓冲了合金阳极的体积膨胀，从而防止了裂纹的产生，避免了电解质的消耗，并确保了高电子传输效率和持续的电化学反应。
