Fuel Cells in Electric Vehicles
The Power of Hydrogen in the Auto Industry
Hydrogen is the most abundant element in the universe. As the world works toward developing more renewable energy sources that emit less pollution, it also makes sense to produce fuel cell technologies that use this highly available element. One such development is the creation of fuel cell electric vehicles (FCEVs) which use hydrogen only to power the engine.
How Do Fuel Cell Vehicles Work?
Though fuel cell cars are considered electric vehicles, hydrogen reacts differently than plug-in or battery-powered hybrid cars. Hydrogen can produce the electricity that powers the car by reacting electrochemically. Compressed hydrogen gas is fed into an onboard fuel cell stack that uses chemical energy to convert fuel into electrical energy instead of simply burning the gas. The resulting electricity is then used to power the car’s electric motor. Because this process does not burn gas and instead transforms it, the only resulting waste is water, so the tailpipe emissions are zero.
Within the fuel cell, hydrogen enters the anode and reaches a catalyst that promotes the separation of elemental hydrogen into a proton and electron. These resulting electrons are collected by the conductive current collector which feeds the motors that turn the wheels and the onboard battery through the car’s high-voltage circuitry.
One can find a deeper understanding of how fuel cell electric vehicles work by examining the car’s key components:
- Auxiliary battery. The low-voltage battery supplies the electricity required to start the vehicle before the traction battery is engaged. This battery also powers accessories in the vehicle.
- Battery pack. Regenerative braking creates energy that is stored by the high-voltage battery. The battery also supplies energy to the electric traction motor if it requires supplemental energy.
- Electric traction motor. This motor powers the vehicle’s wheels using power from the traction battery pack and fuel cell. Some vehicles with more advanced technology have a motor generator that performs both the regeneration and drive functions.
- Fuel cell stack. The assembly of membrane electrodes that use oxygen and hydrogen to produce electricity
- Power electronics controller. This component manages the electrical energy flow delivered by the traction battery and fuel cell to control the speed and torque of the electric traction motor.
- Thermal management system. This cooling system maintains the proper operating temperature range of the electric motor, fuel cell, electronics, and other components.
Benefits of Hydrogen-Powered Vehicles
There are many benefits to hydrogen-powered vehicles, evidenced by the vast amounts of time and development that have been applied to the industry.
First, fuel cell electric vehicles are zero-emission cars. Unlike the historically used fossil fuels, FCEVs produce no harmful emissions. The only by-products are water and heat, making hydrogen both a sustainable and zero-emission fuel source. This lowers the associated cost of the vehicles, as they do not require handling and storing toxic materials. Other reduced costs of the batteries lie in the fact that they do not need to be changed, charged, or otherwise managed, lowering labor and time costs.
FCEVs also have improved efficiency ratings compared to the typical internal combustion engine of a car. Hydrogen fuel cells generally boast a 40% to 60% energy efficiency rating, while the typical gasoline vehicle has about 25% efficiency.
Not only are FCEVs more efficient, but they also have robust reliability. This technology has been proven to continue functionality against the toughest conditions, including frigid environments as low as minus 40 degrees Fahrenheit and harsh weather environments like deserts and hurricanes. Even hardworking, fast-paced work environments can benefit from implementing hydrogen fuel cell vehicles.
The Vehicles of the Future
There is little doubt that hydrogen-powered vehicles will hold a significant part of the market in the future. They have a wide range of benefits that will only increase as the technology develops further.