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负热膨胀行为使得在低温下具有良好的电化学-储能性能
Qiao Li1,2,3, Liting Yang3, Guisheng Liang3
1College of Physics, Donghua University, Shanghai, 201620, China.
Angewandte Chemie (International ed. in English)
|December 9, 2024
概括
具有负热膨胀 (NTE) 的材料可以提高低温电池的性能. 碳涂层的LiTi2(PO4)3 (C-LTP) 在寒冷环境中表现出极好的电化学性能和稳定性,解决了金属离子电池的关键局限性.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 金属离子电池,包括离子电池,是重要的储能设备.
- 由于有限的电化学动力学,低温性能差,阻碍了它们在寒冷气候下使用.
- 需要一种新的战略来克服这些依赖温度的局限性.
研究的目的:
- 研究负热膨胀 (NTE) 材料在提高低温电池性能方面的潜力.
- 为了展示这一策略,使用LiTi2(PO4)3 (LTP) 作为模型材料.
主要方法:
- 使用的LiTi2(PO4)3 (LTP) 具有负的a方向热膨胀系数 (-1.1×10^-6 K^-1).
- 合成碳涂层LTP (C-LTP),以改善电化学性能.
- 评估电化学性能,包括离子扩散率,容量,速率能力和在-10°C时的循环稳定性.
主要成果:
- 与25°C相比,C-LTP在-10°C时表现出强大的电化学性能,保持了84%的Li+扩散率和96%的理论容量.
- 观察到优越的速率能力,与0.5C相比,在5C保持83%的容量.
- 该材料表现出卓越的循环稳定性,在1000个循环中达到96.8%的容量保留,温度为2°C,温度为-10°C.
结论:
- 具有NTE行为的电化学储能材料为改善低温电池功能提供了一个有希望的策略.
- 在较低温度下LTP的独特结构变化,由NTE驱动,促进离子运输和插入.
- 在苛刻的寒冷环境中,C-LTP为高性能,稳定的金属离子电池提供了可行的解决方案.
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