This article will focus on the development history of fuel cells, taking you through some important events in their evolution.
Discovery of Water Electrolysis
The development of fuel cells cannot be discussed without mentioning William Nicholson and Anthony Carlisle. It was their proposal in 1800 to use electricity to decompose water into hydrogen and oxygen that led to a series of subsequent experiments on water electrolysis.
Birthdate of the First Fuel Cell Prototype
In the 1830s, British chemist William Grove had an interesting idea while conducting water electrolysis experiments. He thought that if water could be decomposed into hydrogen and oxygen with electricity, then the reverse process, where hydrogen and oxygen combine to form water, should generate electricity. He disconnected the current, and after doing so, the electrodes became polarized, maintaining a potential difference between them. When an external circuit was connected, a current flowed. Grove named this device the “gas voltaic battery.” This research was published in a philosophical magazine in February 1839, marking the birthdate of the first fuel cell prototype.
Proposal of the Fuel Cell Concept
Fifty years later, renowned chemist Ludwig Mond and his assistant Charles Langer successfully conducted experiments in 1889 to generate electricity using hydrogen and oxygen. They used platinum-coated platinum sheets with large surface areas as electrodes to prevent the catalyst pores from being flooded by the electrolyte, and a porous ceramic base filled with sulfuric acid as the non-flowing electrolyte. This cell produced a current density of 6A/ft² (1ft² = 0.092903m²) at a voltage of 0.73V.
However, this cell had significant drawbacks: it was expensive, had poor reusability, and its performance declined rapidly, limiting its practical application. Despite these issues, the term “fuel cell” was introduced at this time and has been used ever since.
Functions of Various Fuel Cell Components
By 1894, the development of fuel cells had theoretical foundations for guidance. That year, Friedrich Wilhelm Ostwald, a founding figure in physical chemistry, mentioned in a German electrochemical journal the concept of using oxygen from the air to oxidize natural fuels directly through electrochemical principles, without generating heat, to create a power-generating device. He stated, “In the future, the production of electrical energy will be electrochemical, unrestricted by the second law of thermodynamics. Therefore, the energy conversion efficiency will be higher than the efficiency of heat engines.”
Ostwald focused on the theoretical research of fuel cell thermodynamics, proposing many ideas and theories about how fuel cells operate, and experimentally proving the functions of various fuel cell components. His published paper laid the foundation for the field of fuel cells and marked the beginning of extensive research work.
“Coal Battery”
Following this, in 1896, American engineer William Jacques claimed to have developed a “coal battery,” which consisted of a coal anode and an iron cathode immersed in a molten caustic electrolyte with air passing through it. Jacques obtained a current density of 100mA/cm² and a power output of 1.5kW (from a stack of 100 cells) at 450°C from this battery.
However, subsequent research revealed that the anode reaction in Jacques’ battery was the oxidation of hydrogen produced by the reaction between iron and electrolyte water, and the actual efficiency of the battery was only 8%, much lower than Jacques’ claimed 82%. Additionally, the molten sodium oxide was continuously consumed by reacting with the generated CO2, giving the battery a lifespan of only six months.
The First Wave of Fuel Cell Development
During this period, in 1932, Professor Francis Thomas Bacon of the University of Cambridge improved the early Mond-Langer fuel cell. He replaced the acidic electrolyte with an alkaline one (KOH) and used porous gas diffusion electrodes. A layer that prevented gas permeation was applied on the side where the electrodes contacted the electrolyte, preventing gas from passing through the electrodes. After years of research, Bacon obtained a patent for the first alkaline fuel cell in 1959. In 1960, he publicly demonstrated a fuel cell stack with an input power of 5-6 kW. His demonstration led to large-scale research activities in many countries, marking the first wave of fuel cell development.
A New Type of Fuel Cell: Proton Exchange Membrane Fuel Cell
In the late 1950s, W. Thomas Grubb, a chemical researcher at General Electric Company (GE), designed a fuel cell using a sulfonated polystyrene ion exchange membrane as the electrolyte, bringing about a revolution in fuel cells. Three years later, another researcher at GE, Leonard Niedrach, further improved the design by depositing platinum on the membrane, with platinum being the essential catalyst for the hydrogen oxidation and oxygen reduction reactions. This led to the birth of the new fuel cell, the proton exchange membrane fuel cell, also known as the Grubb-Niedrach fuel cell.
Simultaneously, GE developed a small fuel cell for the U.S. Navy’s Bureau of Ships Electronics Division and the U.S. Army Signal Corps, using hydrogen generated from the reaction of water and lithium hydride as fuel. By the 1960s, proton exchange membrane fuel cells began to be commercialized and were used in the Gemini space missions. Unfortunately, due to internal contamination and gas permeation issues with the exchange membrane, they were not used in the subsequent Apollo missions or the Space Shuttle program. Over the next decade, GE made significant advancements in proton exchange membrane fuel cells, which found applications in both military and aerospace fields.
Upgrading Alkaline Fuel Cells
In the early 1960s, the aircraft and engine manufacturer Pratt & Whitney (P&W) obtained the patent rights for Bacon’s stack and redesigned it. By introducing a higher concentration alkaline solution (85% KOH) and lowering gas pressure, the efficiency of the alkaline fuel cell was significantly increased. These P&W fuel cells were later used in the Apollo program.
Revival of Proton Exchange Membrane Fuel Cells
By the 1980s, the application of fuel cells as medium- to small-scale independent power sources became more prominent. Fuel cells could meet the needs of areas beyond the reach of urban power grids and showed promising potential in transportation and portable devices.
Consequently, the Nafion polymer ion exchange membrane developed by DuPont in the U.S. became recognized for significantly improving the performance and lifespan of relatively small fuel cells while effectively reducing platinum loading. This led to a resurgence of interest in proton exchange membrane fuel cells, attracting potential users in new application fields.
The Second Wave of Fuel Cell Development
Starting in the mid-1980s, the number of papers related to proton exchange membrane fuel cells increased rapidly. This was mainly due to two reasons: the growing number of automobiles causing air pollution and the high demand for large-capacity batteries for portable devices. These factors drove continuous research into fuel cells, marking the beginning of the second wave of fuel cell development. The most significant advancements during this phase were in proton exchange membrane fuel cells.
The first proton exchange membrane fuel cell stack used in the Gemini spacecraft had an output power of 1 kW. Due to the high ohmic resistance and insufficient chemical stability of the membrane, the single cell had a current density of less than 100 mA/cm² at 0.6V, a power density of about 60 mW/cm², and a lifespan of less than 2000 hours. However, during the second wave of fuel cell development, the performance of proton exchange membrane fuel cells saw revolutionary improvements. By 1990, the power density had reached 600-800 W/cm², and the lifespan extended to tens of thousands of hours. These breakthroughs were attributed to advancements in various components, leading to the widespread commercialization of improved proton exchange membrane fuel cells.
Proton Exchange Membrane Fuel Cells Become Mainstream
By the late 1990s, proton exchange membrane (PEM) fuel cells had become mainstream, while research on solid oxide fuel cells (SOFC) and high-temperature molten carbonate fuel cells (MCFC) continued. However, research on alkaline fuel cells had significantly decreased since the 1980s.
Entering the 21st Century
In the 21st century, portable fuel cell devices and civilian fuel cell vehicles have been continuously developing. Fuel cell ferries, buses, and rail transit systems have relatively mature strategic deployments and development plans in many countries and regions.
2014: The First Year of Fuel Cell Vehicle Commercialization
The release of the Mirai model in 2014, Toyota’s first mass-produced fuel cell vehicle, marked the beginning of fuel cell vehicle commercialization. Due to its high price and the lack of hydrogen refueling infrastructure, only 6,000 Mirai vehicles were sold worldwide. The Mirai is hand-assembled at Toyota’s Japanese factory, where 13 different factories’ components are put together by workers, producing only 6.5 cars per day. The most expensive component of the Mirai is the fuel cell stack, costing $11,000, which accounts for one-sixth of the car’s total price. Toyota’s system can reduce the production cost of the fuel cell stack to below $8,000 through increased production capacity.
The World’s First Hydrogen-Powered Superyacht
In 2020, the Aqua yacht was introduced, becoming the world’s first hydrogen-powered superyacht. Designed by the Dutch company Sinot Yacht & Architecture, the Aqua yacht features five decks above and two 28-ton vacuum-sealed tanks holding liquid hydrogen below. It has a top speed of 32 km/h and can travel 6,035 km on a full tank of hydrogen. In case of insufficient liquid hydrogen supply, the Aqua yacht can use backup diesel fuel to ensure normal operation.
China’s Hydrogen Vehicle Milestone
In 2022, the number of hydrogen vehicles in China surpassed 10,000 for the first time, reaching 14,979, making it the country with the highest number of hydrogen commercial vehicles globally. China also built 358 hydrogen refueling stations, accounting for nearly 50% of the global total, ranking first worldwide in built, operational, and newly constructed stations. By 2025, it is estimated that China will have 100,000 hydrogen vehicles and over 1,000 hydrogen refueling stations.
Current Fuel Cell Research
In 2023, Russia’s Ural Federal University developed a more environmentally friendly solid oxide fuel cell (SOFC) that can replace acidic, alkaline, and lithium batteries. SOFCs have ceramic metal anodes and porous oxide cathodes. To simplify SOFC production, researchers designed symmetric cells with identical electrode compositions. The new ferrite compounds based on iron, barium, and lanthanum used to produce symmetric SOFCs exhibit high conductivity and low polarization resistance in air. Researchers at Nagoya University in Japan developed a new super-high-density sulfonic acid polymer electrolyte membrane for fuel cells, a key component of eco-friendly polymer electrolyte fuel cells.
Broad Application and Future of Fuel Cells
According to the latest “Global Hydrogen Review 2023” report by the International Energy Agency, the global interest in hydrogen remains high. It is expected that global low-emission hydrogen production will reach 38 million tons per year by 2023, a 50% increase compared to the 2022 report. In December, the Hydrogen Council and McKinsey & Company jointly released an updated “Global Hydrogen Insights” report. The analysis of over 1,400 major hydrogen projects shows that despite challenges like rising interest rates and supply chain constraints, the global hydrogen economy continues to grow. The report states that the total investment in global hydrogen projects has increased to $570 billion, covering production, end-use, and infrastructure, a 35% increase from 2022.
Fuel cell technology is still rapidly developing and being applied, and it is believed that in the future, fuel cell technology will shine brightly and lead us into a hydrogen society.
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