独特的三角形协调量身定制的溶解向高度稳定的金属电池
Junru Wu1,2, Ziyao Gao1,2, Yao Tian1
1Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
Advanced materials (Deerfield Beach, Fla.)
|June 5, 2023
概括
设计具有多氧协调位点的新型电解质溶剂可以提高金属电池的稳定性. 这种策略优化了溶解结构,使得超稳定的循环和在各种条件下提高性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 电池技术 电池技术
背景情况:
- 电解质优化对于稳定 (Li) 金属电池至关重要.
- 离子 (Li+) 与溶剂分子的协调模式在电解质设计中经常被忽视.
- 现有的策略缺乏对溶解结构对电池性能影响的深入理解.
研究的目的:
- 开发一种新的电解质设计策略,该策略基于Li+和溶剂分子的二/三基化.
- 调整溶解结构以提高金属电池的界面稳定性和溶解动力学.
- 为实际的高性能金属电池开发提供指导方针.
主要方法:
- 设计和合成一种具有多个氧气协调位点的新型溶剂.
- 使用设计的溶剂对Li+溶解结构的研究.
- 用LiFePO4阴极和薄的Li薄膜对对称和全细胞进行电化学测试.
- 在570 mAh袋式电池配置中验证.
主要成果:
- 新型溶剂促进了离子聚合溶解的形成,增强了界面稳定性.
- 超稳定的循环超过1400小时,在具有薄Li薄膜的对称细胞中实现.
- 完整电池在500个循环中保持了92%的容量,并且从-10°C到60°C显示出更好的性能.
- 囊细胞在100个循环后显示99.5%的容量保留.
结论:
- 基于二/三基化Li+的电解质工程为稳定金属电池提供了一种有前途的方法.
- 通过溶剂设计调整溶解结构可显著提高界面稳定性和电化学性能.
- 开发的战略为创造实用,高性能金属电池提供了新的方向.
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