Hydrogen vs Lithium – Ion Batteries

Battery electric vehicles, (BEVs) & hydrogen fuel cell electric vehicles, (FCEVs) don't produce any pollution at the tailpipe however, both have the potential to produce pollution when their "fuel" is created.

• The fuel that a (BEV) runs on is electricity, this is used to charge the batteries.
• The fuel that a (FCEV) runs on is hydrogen, this is used to generate the electricity.

 
Are (FCEVs) greener than (BEVs)?

• A (FCEV) runs on a motor powered by electricity.
• What makes a (FCEV) different from a (BEV) is where the electricity comes from.

 
Hydrogen Fuel Cell

• Instead of using a battery, a (FCEV) makes use of a hydrogen fuel cell.
• The hydrogen fuel cell is a device that converts chemical potential energy (energy stored in molecular bonds) into electrical energy. 
• In a PEM (Proton Exchange Membrane) fuel cell hydrogen gas (H2) and oxygen gas (O2) is used as the fuel.
• The hydrogen fuel cell takes hydrogen the most abundant element in the universe and generates electricity from it while the vehicle is running.
• The waste products of the reaction in the fuel cell are water, electricity, and heat.

 
How does the Hydrogen Fuel Cell work?

• A hydrogen atom consists of a (PROTON), this has the positive electric charge and an (ELECTRON), this has a negative electric charge.  Note, hydrogen is the smallest, lightest atom in the universe.
• Inside the hydrogen fuel cell both the hydrogen’s (PROTON) and (ELECTRON) are separated.
• The flow of (ELECTRONS) are free to go their own way to become the electricity that runs the vehicle’s motor.
• For the (PROTON) this becomes a hydrogen ion, this is a hydrogen atom with a positive electric charge, it will bond together with any oxygen atoms in the vicinity to form water.
• Note, water is nothing more than two hydrogen ions with an oxygen atom attached. This process releases a lot of heat so the water becomes steam and the steam becomes the exhaust of the hydrogen fuel cell.

 
 
Where does the electricity and hydrogen come from?
Today, electricity is sourced from a range of power sources; renewables, nuclear, and in the majority of cases electricity is still produced by the burning fossil fuels, coal and gas.
 
In the case of hydrogen, this fuel is mainly produced by the steam reformation of fossil fuels such as natural gas.  With the emerging hydrogen economy “green hydrogen” using the electrolysis of water from wind, hydro or solar photovoltaic energy are viable alternatives that offer zero emission hydrogen energy.
 
(BEVs) and (FCEVs) both have the potential to offer non-polluting forms of transportation, but we do need to quickly move away from producing electricity by burning fossil fuels.   Instead, we need to embrace wind, solar and hydro-electric generation.
 
Concluding comment
 
“Hydrogen has higher energy storage density than lithium ion batteries, both in terms of energy stored per unit weight and energy stored per unit volume”.o edit.