A study of the influence of current ramp rate on the performance of polymer electrolyte membrane fuel cell.

Durability and reliability are the key factors that prevent fuel cells from successful implementation in automotive sector. Dynamic load change is a common and frequent condition that the fuel cell has to undergo in automotive applications. Fuel cells are more sensitive to changes in load conditions and degrade based on load variation representing idling, rated power, and high power operating conditions. To examine the influence of dynamic load step on the fuel cell performance, two similar cells of active 25 cm2 was tested under two different load step for the same dynamic load cycle. The main difference in dynamic load cycle 2 was the ramp rate which was fixed as 0.1, 0.3, and 0.25 A/cm2/s for 0.2, 0.6, and 1.0 A/cm2 respectively. To investigate the degradative effects, polarization curves, electrochemical impedance spectroscopy, and field emission scanning electron microscopy were used. The results indicated that the degradation rate increased in both dynamic load cycles but however the impact of load change was comparatively minimal in dynamic load cycle 2. The total degradation in performance was 20.67% and 10.72% in dynamic load cycles 1 and 2 respectively. Fuel cell performance degraded in a manner that was consistent with the electrochemical impedance spectroscopy and cross-sectional analysis of field emission scanning electron microscopy. The results prove that the degradation rate is dependent on the load step and the number of load cycles. Severe catalyst degradation and delamination were observed in fuel cells operated under dynamic load cycle 1.

A Review on Electric and Fuel Cell Vehicle Anatomy, Technology Evolution and Policy Drivers towards EVs and FCEVs Market Propagation.

The transportation sector is the largest consumer of fossil fuels; making it a major producer of greenhouse gases. Due to declining fossil fuel reserves and increasingly stringent vehicle emission regulations globally, it is essential to shift to alternative energy sources. Economic and eco-friendly fuel-efficient hybrid, electric, and fuel cell vehicles are regarded as one of the best alternative solutions to cope with the government policies and to reduce the rise in global temperature caused by the automotive sector. Technological advancements in fuel cells, batteries, and chargers have further supported the development of electric vehicles. The major challenges of range and charging time in electric vehicles can be countered by range extension technology and developing all-electric hybrid vehicles. In this review, a comprehensive study of different type of vehicles and their architectures are presented. Insights on energy storage devices and converters of electric vehicles currently in use were also provided. Furthermore, various fuel cell advancements and the technical challenges faced during the commercialization of fuel cell vehicles were highlighted.