Effect of Water Conductivity on Proton Exchange Membrane (PEM) Catalyst Durability using Thermal Degradation Resistant Polymer Membranes in Combat Applications
Abstract
The U.S. Army is taking an increasing interest in fuel cell technology as vehicles require more electrical power to support additional capabilities. One challenge the U.S. Army faces using Proton Exchange Membrane (PEM) fuel cells is reduced air flow for primary heat rejection in combat vehicles (due to a small operating space and the use of ballistic grills). Internal temperatures inside the stack increase to 140 deg C resulting in decreased performance. Additives to polymer membranes have been used to mitigate stack heat degradation but can contaminate and increase the electrical conductivity of the stack exhaust water. For water examined here which had a 0.7 mA current applied, an increase in electrical conductivity (using a 5vol percent acetic acid mixture) promoted the platinum electrocatalyst detachment from the PEM fuel cell polymer membrane. The increased water conductivity resulted in 30-40 percent of the total platinum being detached within 67 minutes (400 current cycles).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 30, 2019
- Accession Number
- AD1080495
Entities
People
- T. E. Burye
Organizations
- United States Army Tank Automotive Research, Development and Engineering Center