A Brief History of Proton Exchange Membrane Fuel Cells (PEMFCs)
As early as the 1850s, the process of "ion exchange" was already known, but it wasn't applied to fuel cells until about 100 years later. Liquid electrolytes posed challenges in terms of sealing and circulation, whereas the use of solid electrolytes simplified the structure significantly.General Electric (GE) in the United States was one of the first institutions to research Proton Exchange Membrane Fuel Cells (PEMFCs). T. Grubb and L. Niedrach of GE were the first to develop PEMFC technology. In 1955, Grubb proposed the idea of using ion exchange membranes as the electrolyte, and the method was patented in 1959.
In the 1960s, GE developed PEMFCs using sulfonated polystyrene membranes as the electrolyte. Hydrogen gas was generated through the reaction between lithium hydride (LiH) and water. These PEMFCs were later adopted by the National Aeronautics and Space Administration (NASA) as auxiliary power sources for the Gemini spacecraft. With a power output of 1 kW and a weight of only 32 kg, these fuel cells were remarkably lightweight. Additionally, the water produced during the operation of the fuel cell could be used as drinking water for astronauts.However, there were still several problems at the time, such as low power density (<50 mW/cm²), poor electrochemical stability of the sulfonated polystyrene membrane (with a lifespan of only about 500 hours), and high platinum catalyst loading.
In the late 1950s, alkaline fuel cells began to attract attention. Bacon at the University of Cambridge replaced platinum with the more affordable nickel for the electrodes and used porous gas diffusion electrodes to increase the gas-liquid-solid three-phase contact area, thereby producing high-performance alkaline fuel cells. After being used by NASA in the Apollo lunar missions, research on alkaline fuel cells gained popularity, leading to a decline in interest in PEMFC-related studies.
Following this, GE continued to develop PEMFC technology, with the most significant breakthrough occurring in the mid-1960s when DuPont successfully developed a perfluorosulfonic acid ionomer membrane. This membrane was first applied in the chlor-alkali industry. In the 1970s, GE replaced sulfonated polystyrene membranes with these new perfluorosulfonic acid membranes, significantly improving fuel cell performance and extending cell lifespan to over 57,000 hours.DuPont’s new high-performance membrane, known as the Nafion series, offered key advantages over sulfonated polystyrene membranes:1.The presence of fluorocarbon compounds gave the membrane higher acidity.2.Compared to C–H bonds, C–F bonds were much more stable in electrochemical environments.Despite these improvements, PEMFC development remained slow due to unresolved membrane dehydration issues during operation. GE later addressed this by implementing internal humidification and increasing cathode reaction pressure, which led to the development of the GE/HS-UTC series. However, two main problems persisted:1.The platinum catalyst loading was too high, reaching 4 mg/cm², which made the fuel cells expensive.2.The fuel cells required pure oxygen as the oxidant. Even with pressurized air, the current density could only reach 300 mA/cm², limiting broader application.
In 1983, driven by military needs, the Canadian Department of National Defence showed great interest in PEMFCs and in 1984 funded Ballard Power Systems to begin research. The primary goal was to replace pure oxygen with air as the oxidant. Additionally, graphite plates were proposed as a replacement for the expensive niobium plates used in NASA's fuel cells, to reduce costs.
In 1987, Ballard adopted a new polymer membrane developed by Dow Chemical and used Pt/C as the catalyst. They also incorporated perfluorosulfonic resin into the electrodes to establish proton conduction channels, increasing the three-phase interface and improving Pt utilization. The electrodes and membranes were hot-pressed together to form a Membrane Electrode Assembly (MEA), which reduced contact resistance between membrane and electrodes and achieved a current density of 430 mA/cm².
By the late 1980s, military-driven R&D significantly advanced PEMFC technology. Developed countries like the U.S., Canada, and Germany invested heavily in fuel cell development. For example, the Electric Power Research Institute (EPRI) developed two portable hydrogen-oxygen PEMFC generators for the U.S. military: one with 12V and 500W, and another with 24V and 1000W.
In 1990, Ballard designed and built a 28V, 4 kW methanol-air PEMFC generator for the Canadian Department of National Defence. In June 1994, the department provided an additional CAD 3.7 million for Ballard to build a 40 kW PEMFC system for submarines, completed in 1996. In July 1994, Germany's HDW Shipbuilding Company invested CAD 9.3 million in Ballard to develop and install PEMFCs in their submarines. A PEMFC-powered submarine designed by Siemens for the German Navy was delivered in 1996.
This wave of development, resembling an arms race, significantly matured PEMFC technology. In the 1990s, application efforts shifted toward electric vehicles and backup power stations.
After 1993, Ballard made rapid advancements in PEMFC technology. Following Ballard’s lead, many automakers—Chrysler, Ford, GM, Honda, Toyota, among others—joined fuel cell vehicle R&D, greatly accelerating PEMFC development in the automotive sector.
In the early 1990s, Ballard successfully developed the first-generation MK5 and MK513 PEMFCs. Based on the MK5 stack, Ballard and Daimler-Benz jointly built the first PEMFC-powered electric vehicle. Later, Ballard used the MK513 to assemble a 200 kW fuel cell engine, powered by high-pressure hydrogen, and produced 20 prototype vehicles. These vehicles achieved top speeds and hill-climbing capabilities comparable to diesel engines, with superior acceleration performance.
In 1994, Daimler AG used Ballard's PEMFC stack to build the Necar 1 electric car with 50 kW output. In 1996, they released the Necar 2 (also 50 kW), and in 1997, they developed the Nebus, a 250 kW electric bus.
At the 2008 Beijing Olympics and 2010 Shanghai World Expo, China also deployed PEMFC-powered vehicles, serving as strong demonstrations of the technology.
In late 2014, Toyota announced the commercialization of its fuel cell vehicle, named Mirai ("Future"), and in early 2015, opened 5,680 fuel cell-related patents for free to accelerate industry adoption.
Meanwhile, government investment in PEMFC R&D and infrastructure continues:
The U.S. plans to gradually reduce reliance on oil by advancing technologies such as fuel cells, hybrid power, and biofuels. PEMFC is part of its long-term strategy.
Japan aims to commercialize fuel cell vehicles around 2030.
Additionally, the Direct Methanol Fuel Cell (DMFC) is also a type of PEMFC, since it uses a proton exchange membrane as the electrolyte. Interestingly, DMFC technology actually predates PEMFC. Initially, it used liquid electrolytes. As early as 1951, Kordesch and Marko studied direct alcohol (methanol and ethanol) and formaldehyde fuel cells using carbon electrodes in KOH solution. Later, researchers at Allis-Chalmers also tested DMFCs with alkaline electrolytes.
In 1965, researchers at Shell and ESSO began using acidic electrolytes, which did not react with CO₂, a product of the reaction. For decades afterward, DMFCs garnered little attention—until 1992, when the success of Nafion in PEMFCs revived interest. With structural similarities to PEMFCs, DMFCs have since been recognized as a variant of PEMFC.