瓦纳氧化还原流电池的可靠性研究:上限电压效应
Rajankumar Patel1, Qian Huang1, Bin Li1
1Battery Materials & Systems Group, Pacific Northwest National Laboratory Richland WA 99352 USA Qian.Huang@pnnl.gov.
RSC advances
|October 29, 2024
概括
全氧化还原流电池 (VRFB) 的高上电压加快了降解,降低了效率和寿命. 在电网应用中,优化电压限值对于可靠的长期储能 (LDES) 是至关重要的.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 全氧化还原流电池 (VRFB) 对长期储能 (LDES) 是有前途的.
- 随着时间的推移,性能色是VRFB可靠性的一个主要挑战.
- 了解降解机制是改善VRFB寿命的关键.
研究的目的:
- 系统地调查上限电压增加对VRFB可靠性和退化的影响.
- 在高电压下识别主要降解贡献者 (阳极/阴极).
- 为了将电化学性能与电极材料的变化相关联.
主要方法:
- 长期循环测试 (500+循环) 的缩放VRFB细胞 (49厘米2).
- 不同的上限电压 (1.6V, 1.7V, 1.8V).
- 电化学阻抗光谱 (EIS),极化曲线和电极特征 (形态,表面).
主要成果:
- 较高的上电压显著降低容量和电压效率.
- 电解质再混合部分恢复了1.7V和1.8V的电压效率,表明降解.
- 充电期间的阳极降解和放电期间的阴极降解被更高的电压放大,阳极受到更大的影响.
- 升高的电压会增加电阻,主要是由于阳极的电荷传输电阻.
- 阴极在1.8V时表现出严重的表面退化.
结论:
- 优化电压限制对于提高VRFB寿命至关重要.
- 降解取决于电压,具有特定的阳极和阴极贡献.
- 加快压力因素寿命测试 (ASLT) 协议可以为VRFBs提供预测模型的信息.
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