Hydrogen Fuel Cell

Hydrogen Fuel-Cell Cars


2016 Toyota Mirai Hydrogen Fuel Cell Car

The Ultimate Information Guide to Understand Hydrogen Fuel-Cell Cars

Hydrogen is the most abundant element on the planet. It is also an alternative fuel that has the potential for near-zero greenhouse gas emissions. Fuel cell electric vehicles (FCEVs) are powered by hydrogen, which generate power in a fuel cell. They are more efficient than conventional internal combustion engine vehicles and emit only water vapor and warm air. Below, we explore what this new technology is, how it works, what the categories are, as well as the pros-and-cons.



What Are Hydrogen Fuel Cell Cars?

Definition

Hydrogen Fuel-Cell Car Definition

Hydrogen fuel-cell cars are those vehicles that uses the natural element of hydrogen gas (Symbol: H) as their main fuel source. The main component of a hydrogen powered car is its fuel cell. Simply put, fuel cells convert stored hydrogen-gas into electricity, which powers an electric motor to propel the vehicle with virtually no tailpipe emissions.

Explained

Hydrogen Fuel-Cell Cars Explained

Hydrogen powered cars, sometimes referred to as a Fuel Cell Vehicle (FCV) or Fuel Cell Electric Vehicle (FCEV) use a completely different propulsion system than conventional vehicles. High pressure hydrogen gas is stored in tanks, similar the same way gasoline or diesel is stored in combustion powered vehicles. This hydrogen gas is later converted to energy by the fuel cell, to power the electric motor and propel the vehicle. Because the vehicles run on pure hydrogen gas (the most abundant element on planet earth), they are significantly more efficient than a gasoline powered vehicles.

The fuel cell is the most important component to a hydrogen car. So much, that hydrogen cars are sometimes referred to as “Fuel Cell Vehicles” (E.g. Toyota Mirai Fuel Cell Vehicle). Fuel cells are easier to understand if thought of as a rechargeable battery. They pull fuel from a tank of stored hydrogen (similar to how electricity is pulled from batteries) to generate onboard electricity and power an electric motor to drive the car.


2016 Toyota Mirai Hydrogen Fuel Cell Car
2016 Toyota Mirai


History of Hydrogen Fuel Cell Vehicles

Fuel cells are not a modern development. Although iterations of what may technically be considered to be a fuel cell existed before, the term fuel cell first emerged in 1889 from two chemists named Ludwig Mond and Charles Langer when they attempted to build the first practical ‘gas battery’ device using air and industrial coal gas.

Advancements in fuel cell technology continued well into the next century, with commercial applications in manned spaceflight and aerospace. It wasn’t until the 1960’s and 1970’s that consumer automotive applications of fuel cell technologies were seriously considered for the mass-market. The United States Oil Crisis of 1970’s accelerated this interest, causing auto giants such as General Motors (GM) to begin seriously putting forth efforts to produce engines that were hydrogen-fueled. By the time the 1980’s came around, almost all automobile manufacturers had at least a demonstration model of hydrogen-fueled fuel cell vehicle. Technical breakthroughs continued throughout the decade, leading up to the development of the first marketable fuel cell-powered vehicle in 1993 by the Canadian company, Ballard Power Systems.

Driven by growing global pressure to meet increasingly rigorous environmental requirements and reduce oil dependency, the effort to develop fuel cell technologies for cars has only continued. As consumers and government agencies continued to express more concern over carbon dioxide emissions, researchers turned their attention to cars that can make use of fuel cell technologies to reduce the way the auto industry depends on fossil fuels.

Recent years has seen increased government funding for research into hydrogen fuel cell technology and steps have been taken to reduce the cost of using hydrogen fuel cells down to a more competitive level with other technologies for vehicles, such as fully electric or clean diesel. Today, hydrogen fuel cells can be found in public buses, government utility vehicles, and a growing number of consumer cars.



How Do Hydrogen Fuel Cell Cars Work?

Hydrogen powered cars and battery powered fully electric cars have a lot in common. They both have electric motors and similar drivetrains. The core component, fuel cells, are like a cross between an internal-combustion engine and battery power. Similar to internal-combustion engines, fuel cells generate their power by using fuel from a tank, in the form of pressurized hydrogen. The key difference is that the fuel is not burned, instead, fuel cells chemically fuse the tank-fed hydrogen with oxygen to make water. In the process, which resembles what happens in a battery, electricity is created and harnessed to power the electric motor (or motors) that drive the vehicle.

How do hydrogen fuel-cell cars work diagram?
The following technologies are core components to hydrogen powered cars:

  1. Fuel Cells - Fuel cells can be thought of as batteries that never run flat. Instead of slowly depleting the chemicals inside them (as normal batteries do), fuel cells run on a steady supply of hydrogen and keep making electricity for as long as there's fuel in the tank. Electricity is produced through a chemical reaction between a source fuel and an oxidant (The source fuel being hydrogen gas). As such , the only byproducts are water and a small amount of nitrous oxide if air is used as the oxidizer.

    Fuel Cell Stack - Since individual cells generate relatively small amounts of electricity, they are grouped together into what are called Fuel cell stacks. Some fuel cell stacks contain hundreds of individual fuel cells, each producing less than one volt. Together, these fuel cell stacks produce enough power to propel the vehicle.

  2. Hydrogen Storage Tank - Hydrogen fuel tanks come in mainly two different types: 1) Compressed hydrogen gas 2) Cryogenic hydrogen (super-cooled liquid hydrogen). Since hydrogen gas is the more common of the two, most common fuel tanks are setup for hydrogen gas storage. The gas is stored in a compressed state in high-pressure tanks, located either in the trunk or under the floor of the vehicle. Hydrogen fuel is sourced from these tanks to feed the fuel cells. These tanks are connected to the fuel port (where the gas is dispensed into from refueling stations). Most hydrogen fueling stations dispense compressed hydrogen gas at 5,000 psi and 10,000 psi or at both pressures.

  3. Electric Motor - Similar to an electric car, hydrogen cars use an electric motor located near the vehicle’s front wheels to power propulsion. The electric motor propels the vehicle with little noise or vibration. It gets its power from the electricity generated by the fuel cells. It can also source energy through regenerative braking technology, where the electric power is stored in a battery pack and later drawn out it to supplement torque and power.

  4. Motor Controller (Control Unit) - The power control unit manages and governs the flow of electricity generated in the fuel cell, as well as battery input/ouput in accordance with driving conditions. The amount of electricity converted and fed to the electric motor, is based on the input delivered from the accelerator pedal. By drawing power from either the battery or fuel cell stack, it delivers electric power to the motor, which then uses the electricity to propel the vehicle.




Hydrogen Fuel Cell Car Pros and Cons

Pros

  • Reduced Pollution - Hydrogen is the most abundant element on planet earth and can be made from renewable energy. The only byproduct created from hydrogen cars is heat and water (i.e. steam).

  • Fuel Efficient - Overall fuel economy for hydrogen fuel cell powered vehicles is the equivalent of about twice that of gasoline vehicles. They convert up to 75 percent of the fuel into usable energy and can drive distances of up to 300 miles (480 kilometers) on a single tank. Fuel cell vehicles are often equipped with regenerative brakes, which also contribute to their increased efficiency.

  • Reduced Maintenance - Lesser internal moving parts (when compared to combustion engines) means lower maintenance related costs. Hydrogen powered vehicles are also quieter, smoother, and frequently lighter in weight (when compared to electric vehicles) for less wear and tear.

  • Longer Driving Range - Since hydrogen powered vehicles are able to densely pack their energy storage, this translates into longer distances travelled before requiring a fill up. While most fully electric vehicles can travel between 100-200 miles on a single charge, hydrogen vehicles can travel into the 300 mile or around 480 kilometer range on a single fill up.

  • Fast Refuelling - Although the amount of fill up stations are limited, the actual amount of time it takes to pump hydrogen into your tank is quite reasonable. Where charging a fully electric vehicle may take several hours, filling up a hydrogen car can refill in only a few minutes, with enough fuel to travel several hundred miles.


Cons

  • Lacking Infrastructure - There is currently lacking sufficient infrastructure to support hydrogen refueling on a mass scale. According to U.S. Department of Energy, there are currently less than 50 publicly available hydrogen refuelling stations in the United States. However, government initiatives and auto manufacturers are investing to make refuelling stations commonplace.

  • Vehicle Production Costs - Platinum is one of the most commonly used catalysts for fuel cells. At almost $1,000 an ounce, platinum can be a very expensive commodity. This increased production material cost, along with other new technologies related to hydrogen powered vehicles, are often folded into the purchase price of the vehicle. The result of this is a vehicle sticker price significantly higher than a comparable gasoline powered car.

  • Potential Dangers - Storing pressurized hydrogen onboard your vehicle can pose unique dangers. One of the main concerns is that Hydrogen flames are nearly invisible. In the event of a collision, this would be of great concern to first responders attempting to rescue passengers.

  • Hydrogen Storage - Storing hydrogen is a challenge because it requires high pressures, low temperatures, or chemical processes to be stored compactly. For consumer passenger cars, overcoming this challenge is a bit difficult because they often have limited size and weight capacity for fuel storage.

  • Climate Sensitivity - For proper performance, hydrogen-powered cars have some temperature parameters. In places where the temperature goes below the freezing point, hydrogen powered cars run the possibility of the water in the fuel cells freezing. In places with high temperatures, fuel cell components run the risk of overheating.