自热诱导的树突的愈合
Lu Li1, Swastik Basu1, Yiping Wang2
1Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
概括
高电流密度可以令人惊地治愈可充电电池中的树突. 这种自我修复机制使硫电池能够稳定循环并提高效率.
科学领域:
- 材料科学
- 电化学
- 能量储存
背景情况:
- 金属电极对于高能量密度的可充电电池至关重要.
- 在涂层/剥离过程中,树的生长会导致电池故障和安全问题.
- 这一问题通常会因高电流密度而恶化.
研究的目的:
- 调查一种不寻常的 dendrite 进化过程.
- 探索高电流密度对树突的缓解的潜力.
- 为了实现硫电池的安全和高效循环.
主要方法:
- 在不同电流密度下对涂层和剥离进行实验研究.
- 监测树形态和表面演变.
- 对金属电极进行高电流密度处理.
- 有处理电极的循环电池.
主要成果:
- 确定了状体自我愈合的临界电流密度值 (~9 mA/cm2).
- 高电流密度会诱导自热,促进表面的迁移和愈合.
- 重复的高电流密度处理有效地平滑了表面.
- 证明了高库伦比效率的硫电池安全循环.
结论:
- 高电流密度可以通过自我愈合来逆转树生长的有害影响.
- 这种新的方法为部署无树的金属阳极提供了途径.
- 能够开发更安全,高性能的可充电电池,特别是硫系统.
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