FCEVs are alsocategorized as zero-emissions as they are electrically propelled vehiclespowered by hydrogen emitting water.
Fuel cell electric vehicles can typicallybe categorized as all electric vehicle type, as it has very similar powertrainto the BEV. The energy source of the car is from fuel cell stack that consumesHydrogen as the fuel producing electricity, water and heat as end products withno exhaust pollutant, making it a zero emission vehicle. The fuel cell can beof various types such as direct methanol fuel cells, alkaline fuel cells,phosphoric acid fuel cells etc. The polymer electrolyte membrane is the mostpreferred fuel cell for production cars. It has high power discharge and loweroperating temperature. It has high corrosion resistance compared to the othertypes of fuel cells 30. Highlypressured hydrogen stored in a tank mounted in the vehicle is used as the fuel.Fuel cell is the best options for a constant power supply but does not satisfythe needs for a sudden change in power demand.
Vehicles withslower speed like trams, buses, forklifts etc. are best fit for fuel cellapplication. With recent technological advancement, fuel cells are designed andused in high-speed vehicles such as cars.
Asian Automakers like Hyundai, Toyotaand Honda have the leadership in this technology while producing highperformance fuel cells for their vehicles. Various energy management strategiesare adopted focusing on improved fuel economy, improved vehicle efficiency andreduced energy losses. General Electricmanufactured the first fuel cell electric car, the Electrovan in 1966. The Carwas powered by an alkaline fuel cell with two cooled tank vessels for liquidhydrogen and liquid oxygen. The fuel cell stack is the main component of thecomplete fuel cell power train. Based on temperature of operation a wide rangeof fuel cells are available including mild and high temperature fuel cells. Theproton conducting polymer membrane type of fuel cell used in automotiveapplication operates at low temperature.
They combine the hydrogen and oxygenat a comparatively low operating temperature from 60 to 80 °C with high power density,also with the potential of being manufactured at low cost. Polymer membranetype fuel cell based power systems give similarperformance features compared with combustion engines. The stack for the fuelcell is constructed from hundreds of single cells (similar to electric carbattery) converts’ chemical energy into electrical energy.
The fuel (Hydrogen)is channeled to the electrode through fuel supply system. Availability of amplequantities of fuel and oxidants at the electrodes; result in the generation ofelectrical energy. Removing of the end product, which is water, and thecontinuous supply of fuel to the single cells of the stack is the challenge todesign the system. 34The fuel cellcars use a compressed hydrogen fuel storage system with either in 350 Bar or700 Bar pressure. The single vessel tank system is used for the storage ofhydrogen with specific energy of 1600 Wh/kg. This results in 4-7 kg of hydrogenthat can be stored in the tank. 35 The ultimatum for production of fuel cell vehicleis in terms of safety and ability to manufacture such high-pressure storagetank for integrating into the car.
Toyotas fuel tank for the latest Miraistores the high-pressured hydrogen in tanks that are capable of withstandingsmall-caliber bullets. 36 In existing vehicles some level of modification isneed to accommodate the compressed hydrogen fuel tank. Conventionally designedcar for accommodating combustion engine does not have ample space for thehydrogen storage to provide the range. Typically the rear body modifications mustbe made to integrate the hydrogen storage. The hydrogen fuelcell is very effective alternative when used in vehicles that can accommodatelarger tanks to provide larger range such as trucks.
The technology integrationin cars will definitely restrict the range of the car due to the low spaceavailability for larger storage tanks to accommodate the high-pressurehydrogen. The primary set back of fuel cell vehicles to enter the system is thelack of infrastructure for refueling of hydrogen. When adopted in cars, thesystem itself is very expensive and the fueling stations are not availabile formass adaptation. Most countries currently have next to no hydrogen fuellingstations.
This makes the fuel cell vehicles highly impractical. Even though thecar does not produce harmful emissions, production of the fuel (high pressuredhydrogen) consumes a lot of energy. This does not balance the totality in thesupply chain.