关于微流场输出性能的研究:肋骨/通道尺寸的影响和对操作条件的敏感性
Shengnan Xu1,2, Yirui Lu1,2, Daijun Yang1,2
1School of Automotive Studies, Tongji University, Shanghai 201804, China.
ACS omega
|October 21, 2024
概括
带有微流场的不钢双极板显著提高了燃料电池功率密度. 在低湿度和更高的温度下实现最佳性能,显示出更好的质量转移和减少水积累.
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:
- 双极板设计对于燃料电池性能至关重要,影响质量转移,水排放和电子运输.
- 减少双极板厚度和利用微流场 (<1毫米) 是高功率密度堆的关键,但需要进一步的实验验证.
研究的目的:
- 实验性地研究使用微流场 (0.2:0.8毫米,0.3:0.7毫米,0.5:0.5毫米) 的不钢双极板的性能.
- 为了评估这些微流场对阴极湿度,入口压力和工作温度的灵敏度.
主要方法:
- 制造三块不钢双极板,肋骨/通道宽度不同 (0.2:0.8毫米,0.3:0.7毫米,0.5:0.5毫米).
- 对这些板的实验测试与石墨对照 (1.0:1.0毫米).
- 分析不同阴极入口湿度 (RHc),阳极/阴极压力 (Pa/Pc) 和电池温度 (Tcell) 的性能.
主要成果:
- 与石墨G1.0/1.0板相比,SS-0.5/0.5板实现了59.05%更高的峰值功率密度.
- 在低阴极入口湿度 (RHc) 时观察到最佳性能.
- 高RHc (60%) 导致水的积累,并在高电流密度下增加了质量传输阻力.
- 微流场对阳极/阴极压力的敏感性是可以忽略不计的.
- 细胞温度的升高显著降低了度损失,并缓解了水的积累.
结论:
- 不钢双极板中的微流场与传统石墨板相比,提供更高的功率密度.
- 操作条件,特别是低湿度和高温,对于最大限度地提高微流场设计的效率至关重要.
- 需要进一步研究高湿度和流密度的微流场中的水资源管理.
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