在过电的情况下,离子电池中的电解质副产品DMDOHC的变化特征
Yulai Wei1, Ziyi Wang1, Zifeng Ming1
1State Key Laboratory of Power Transmission Equipment Technology, and National Innovation Center for Industry-Education Integration of Energy Storage Technology, Chongqing University, Chongqing, China.
概括
过度充电离子电池会产生2,5-二氧化二氧化酸二甲基 (DMDOHC),加速电池的老化. 在过度充电条件下,DMDOHC度是评估离子电池健康状况的关键指标.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 离子电池随着时间的推移而降解,特别是在电力滥用下,如过度充电.
- 过充电期间的电解质分解会产生老化产品,影响电池性能.
- 2,5-dioxahexanedioic酸二甲基 (DMDOHC) 被确定为一个显著的衰老产品.
研究的目的:
- 调查DMDOHC度与离子电池在过充条件下老化之间的相关性.
- 建立DMDOHC作为电池健康状况监测的潜在指标.
- 探索过充电电压和循环对DMDOHC形成的影响.
主要方法:
- 开发一个用于检测DMDOHC的拉曼光谱平台.
- 用不同的DMDOHC度制备电解质样本.
- 在不同的充电切断电位 (3.8V至4.4V) 下对LiFePO4电池进行循环实验.
主要成果:
- 随着切断电压的提高,DMDOHC度增加,从3.8V的144.07 ppm增加到4.4V的553.28 ppm.
- 增加的DMDOHC水平与加速的电池容量衰减和更高的衰老率相关.
- 在4.4V时,DMDOHC显示出显著的增长,与电池周期数量有正相关性.
结论:
- DMDOHC度是一个可靠的指标离子电池在过度充电下老化.
- 这一发现为先进的电池健康评估提供了理论基础.
- 拉曼光谱为监测DMDOHC和评估电池状态提供了一种可行的方法.
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