What is the effect of subzero temperatures on PEM fuel cells?
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Subzero temperatures have several effects on PEM fuel cells. Firstly, the presence of subcooled water at subzero temperatures can lead to ice blockage inside the cathode catalyst layer (CCL) . This blockage can occur at the CCL and cathode microporous layer (CMPL) interface at temperatures higher than -13 °C . The pore size of the CCL also plays a role in the cold start of PEM fuel cells, with a critical pore size determining the location of blockage within the fuel cell . Additionally, during cold startup tests, the cell resistance increases as the temperature decreases . However, external assisted techniques, such as using an external heat source, can help improve the cold start performance of PEM fuel cell stacks at subzero temperatures . Overall, subzero temperatures can impact the performance and cold start capabilities of PEM fuel cells, but strategies such as considering pore size and using external heat sources can mitigate these effects.
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| Papers (5) | Insight |
|---|---|
| The effect of subzero temperatures on PEM fuel cells is that ice formation is delayed and the formation rate is decreased, allowing the fuel cell to start at subzero temperatures. (Answer is in the paper) | |
01 Jan 2023 | The paper investigates the cold start capabilities of a PEM fuel cell under subfreezing temperatures, but it does not explicitly mention the effect of subzero temperatures on PEM fuel cells. |
01 Jan 2023 | The paper discusses the effect of subzero temperatures on a polymer electrolyte fuel cell (PEFC). It mentions that during operation at subzero temperatures, water generated by the oxygen reduction reaction tends to freeze, leading to an increase in cell resistance. |
2 Citations | The effect of subzero temperatures on PEM fuel cells is that they limit the self-cold start ability of the fuel cell system, requiring an external heat source for operation. |
| The paper states that at ambient temperatures lower than -13 °C, ice blockage occurs inside the cathode catalyst layer (CCL) of PEM fuel cells. |
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