Fuel Cells Vs Batteries: Why The Status Quo?

Despite the many advantages of fuel cells, they have not replaced batteries. Fuel cells and batteries are both part of the solution for a greener future, but they still have some environmental impacts. Fuel cells, for example, require hydrogen-rich fuel, which, depending on the production method, may or may not be environmentally beneficial. Similarly, the electricity used to charge batteries can come from renewable or non-renewable sources, impacting the environment. Batteries are currently the more mature solution, having been around for over 200 years, and are the preferred energy source for most automotive applications. However, fuel cells offer faster refuelling and are more suitable for commercial vehicles like buses, trains, trucks, and airplanes.

Hydrogen fuel cells are less efficient than batteries

In practical terms, this means that battery-powered electric vehicles (EVs) can travel further on a single charge than hydrogen fuel cell vehicles. This is a significant advantage for EVs, as it means they can be used for longer-distance travel without needing to stop to recharge.

Additionally, the charging infrastructure for EVs is already well-established, making it more convenient for users to recharge their vehicles. In contrast, refuelling locations for hydrogen fuel cell vehicles are still sparse, and the cost of fuelling is similar to traditional fuels.

The production and distribution of hydrogen also present challenges. Hydrogen must be produced using renewable energy sources to be truly carbon-neutral, and even then, distribution and storage costs can be prohibitive.

Furthermore, while hydrogen fuel cell vehicles offer faster refuelling times similar to traditional petrol vehicles, this advantage is somewhat offset by the limited refuelling infrastructure.

As a result of these factors, hydrogen fuel cells have not yet replaced batteries as the dominant power source for electric vehicles.

Hydrogen fuel cells are highly flammable and explosive

However, it's important to note that hydrogen fuel cells have been used safely for decades in various applications, including rocket fuel and fertilizer production. Industry experts and engineers have developed robust safety protocols to mitigate the risks associated with hydrogen's high flammability and low ignition energy. For instance, sensors are mandatory at hydrogen fueling stations, equipment, and facilities to detect leaks promptly. Hydrogen storage tanks in fuel cell cars are also rigorously tested under extreme conditions before deployment.

Despite these safety measures, the flammability and explosivity of hydrogen remain a concern for some. The challenge of storing hydrogen safely and cost-effectively in fuel cell trucks and airplanes persist, and the transportation industry must achieve stringent safety targets. Additionally, the distribution and storage of hydrogen for vehicles remain a significant hurdle, requiring a costly infrastructure setup.

While hydrogen fuel cells offer environmental benefits and efficient energy output, addressing the safety concerns around their flammability and explosivity is crucial for gaining widespread acceptance and realizing their long-term potential.

Batteries are more energy-efficient than fuel cells

Batteries and fuel cells are both part of the solution for a greener future, but batteries are the more mature solution, having been around for over two hundred years. They are also more energy-efficient than fuel cells.

While no energy source is 100% efficient, batteries suffer significantly lower energy losses than fuel cells. They can reuse between 80-90% of the chemical energy stored, and some of the energy lost to heat can be reused for other purposes, such as heating an EV's cabin or warming up meals in airplanes. This process, known as cogeneration, is used by EV manufacturers to reduce battery drain.

In contrast, fuel cells generally transform only 40-60% of their energy to produce electrical power. While using cogeneration from waste heat can theoretically improve fuel cell energy efficiency to as high as 85%, it still falls short of the efficiency of batteries.

Fuel cells become almost as efficient as batteries in cold weather, as EV batteries use up to 40% of their electrical energy for heating. However, batteries remain the more efficient option overall.

The higher efficiency of batteries is one of the reasons why hydrogen fuel cells are unlikely to catch up to battery-electric vehicles, even for commercial trucks. The infrastructure required for hydrogen fuel cells is also a significant challenge, as it would require building an entire hydrogen production, transport, storage, and distribution industry.

Batteries are faster to charge than fuel cells

One of the most significant drawbacks of electric vehicles (EVs) is the time it takes to charge them. Charging an electric battery takes much longer than refuelling a fuel-cell vehicle. For regular EV batteries, a full charge can take anywhere from 45 minutes to 2 hours. In the best-case scenario, fast charging still takes between 20 to 25 minutes. To achieve faster charging, batteries need to be maintained within specific temperature ranges. They may need to be cooled down due to the heat generated by the incoming current, and in colder environments, they may need to be heated up as batteries cannot be charged below 0°C.

The charging time for larger batteries, such as those found in commercial vehicles like delivery trucks, buses, trains, and airplanes, is even longer. This is because charging stations have not yet been adapted to accommodate the higher power requirements of larger batteries. For instance, many EV buses require 4 to 5 hours to charge, which is impractical in many situations.

In contrast, refuelling a fuel-cell vehicle is much faster and comparable to refuelling a gasoline car. Fuel-cell tanks are filled with hydrogen-rich fuels, and the process only takes a few minutes. This makes fuel cells very attractive for commercial vehicle applications as it reduces charging times to practical levels.

The lengthy charging times of EV batteries, especially for larger batteries, pose a significant challenge to their widespread adoption, especially for commercial vehicles that require quick refuelling to maintain operational efficiency.

However, it is worth noting that most EV charging is done at home overnight, which compensates for the longer charging times to some extent. Additionally, advancements in charging technology, such as Tesla's recent announcement of a charging station capable of delivering over 1 MW of power, hold promise for reducing EV charging times in the future.

Hydrogen fuel cells have less infrastructure

The infrastructure for hydrogen fuel cells is sparse, and the cost of developing the technology, as well as storing and moving hydrogen, is high. Hydrogen fuel cell vehicles require specialized refuelling stations, whereas most EV charging is done at home overnight. This lack of infrastructure for hydrogen fuel cells is a significant barrier to their widespread adoption.

Additionally, hydrogen fuel cells have struggled to gain traction in the market despite significant investments and efforts by major automakers such as Toyota, Hyundai, and GM. Their programs, such as the Toyota Mirai and Hyundai Nexo, have failed to gain traction even after years of investment. This suggests that the lack of infrastructure is a critical factor in their limited success compared to battery-electric vehicles.

The challenge of building a hydrogen infrastructure is further exacerbated by the need to produce hydrogen sustainably. Traditional methods of producing hydrogen can generate as much carbon dioxide as the fuel cell process saves. Therefore, ensuring a renewable source of hydrogen, such as wind, solar, or hydro-electric power, is crucial but currently insufficient to meet the demand.

In summary, hydrogen fuel cells have less infrastructure than batteries, and building a comprehensive hydrogen industry faces significant challenges and costs. This lack of infrastructure is a critical factor in why hydrogen fuel cells have not replaced batteries, and it continues to be a hurdle for their widespread adoption.

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