在离子电池中,通过添加剂-溶剂优化,将固体-电解质介面相结合稳定,并抑制石墨剥落
Sanghamitra Moharana1, Geoff West1, Ashok S Menon1
1Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, U.K.
ACS applied materials & interfaces
|October 18, 2023
概括
将六酸 (KPF) 添加到碳酸 (PC) 电解质中,可以防止离子电池中的石墨脱皮. 这种KPF添加剂提高了电池的稳定性和性能,在更广泛的温度范围内.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 碳酸 (PC) 是离子电池 (LIB) 的潜在溶剂,因为它具有高介电常数和稳定性.
- 然而,PC可以导致石墨脱皮,电解质分解和LIBs中的容量损失.
研究的目的:
- 用六酸 (KPF) 作为添加剂来制备三元电解质,以减轻PC诱导的石墨剥落.
- 调查KPF6对电解质稳定性,电极/电解质间相形成和电池整体性能的影响.
主要方法:
- 在最佳度 (0.1M) 时制备含有PC和KPF的三元电解质.
- 电化学测试以评估电池循环性,Li+运输,以及抑制石墨剥落和Li树突形成.
主要成果:
- 该KPF6添加剂通过改变K+溶解扩散速率来减少PC分解和干.
- 在0.1M KPF6时形成了一个强大的,富含LiF的电极/电解质介面,有效地抑制了石墨脱皮和Li树突的生长.
- 通过富含LiF的介面阶段进行增强的Li+运输导致了稳定的可循环运行.
结论:
- 有KPF6添加剂的三元电解质成功解决了在LIB中使用PC的挑战.
- 这种配方使得无脱皮和无树的石墨阳极成为可能,提高了电池的安全性和循环寿命.
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