Hybrid Vehicle and
Fuel Cell technology


A Hybrid Vehicle can use a Fuel Cell in stead of ICE.



A Fuel Cell is designed to convert hydrogen rich fuels into electrical energy that is stored in the vehicles battery pack.

A fuel cell vehicle can be made to operate from a variety of hydrogen fuel sources including pure hydrogen, methanol and gasoline.

A fuel cell vehicle will use the stored electrical energy to drive a 50kW or larger electric motor. Some vehicles will use more than one electrical motor to directly drive 2 or 4 wheels.

A properly running fuel cell will produce electrical energy and pure water.

Currently three main issues hinder the widespread use of fuels cells.

1. how to transport and store hydrogen fuel in the vehicle.

2. the cost of producing a powerful fuel cell is high.

3. the size and weight issue as fuel cells powerful enough to power a car or truck are still rather bulky and heavy.

However technology is maturing fast, so fuel cells may well prove to be a viable option in automotive technology in the not so distant future.

Types of Fuel Cells


Fuel cells are classified primarily by the kind of electrolyte they employ. This determines the temperature range in which the cell operates, the fuel required, and other factors. These characteristics, in turn, affect the applications for which these cells are most suitable.

The types are:

* Polymer Electrolyte Membrane (PEM) Fuel Cells
* Direct Methanol Fuel Cells
* Alkaline Fuel Cells
* Phosphoric Acid Fuel Cells
* Molten Carbonate Fuel Cells
* Solid Oxide Fuel Cells
* Regenerative Fuel Cells
* Comparison of Fuel Cell Technologies

Of these types practically only the Polymer Electrolyte Membrane (PEM) is practically applicable for automotive use.

Phosphoric Acid Fuel Cells have been used in buses but are generally to large and heavy to be practical in other than large heavy vehicles.


Polymer Electrolyte Membrane (PEM)
Fuel Cells

From the US Department of Energy

PEM Fuel Cell

Diagram: How a Polymer Electrolyte Membrane (PEM) fuel cell works. A PEM fuel cell consists of a polymer electrolyte membrane sandwiched between an anode (negatively charged electrode) and a cathode (positively charged electrode).

The processes that take place in the fuel cell are as follows:

1. Hydrogen fuel is channeled through field flow plates to the anode on one side of the fuel cell, while oxygen from the air is channeled to the cathode on the other side of the cell.

2. At the anode, a platinum catalyst causes the hydrogen to split into positive hydrogen ions (protons) and negatively charged electrons.

3. The Polymer Electrolyte Membrane (PEM) allows only the positively charged ions to pass through it to the cathode. The negatively charged electrons must travel along an external circuit to the cathode, creating an electrical current.

4. At the cathode, the electrons and positively charged hydrogen ions combine with oxygen to form water, which flows out of the cell.

Polymer electrolyte membrane (PEM) fuel cells—also called proton exchange membrane fuel cells—deliver high power density and offer the advantages of low weight and volume, compared to other fuel cells. PEM fuel cells use a solid polymer as an electrolyte and porous carbon electrodes containing a platinum catalyst. They need only hydrogen, oxygen from the air, and water to operate and do not require corrosive fluids like some fuel cells. They are typically fueled with pure hydrogen supplied from storage tanks or onboard reformers.

PEM fuel cells are reliant on a supply of clean Hydrogen which puts rigorous demands on the fuel supply infrastructure.


Phosphoric Acid Fuel Cells


From the US Department of Energy

PAFC Fuel cell

Diagram: How a Phosphoric Acid Fuel Cell (PAFC) works. A PAFC consists of liquid phosphoric acid electrolyte sandwiched between an anode (negatively charged electrode) and a cathode (positively charged electrode).

The processes that take place in the fuel cell are as follows:

1. Hydrogen fuel is channeled through field flow plates to the anode on one side of the fuel cell, while oxygen from the air is channeled to the cathode on the other side of the cell.

2. At the anode, a platinum catalyst causes the hydrogen to split into positive hydrogen ions (protons) and negatively charged electrons.

3. The phosphoric acid electrolyte allows only the positively charged ions to pass through it to the cathode. The negatively charged electrons must travel along an external circuit to the cathode, creating an electrical current.

4. At the cathode, the electrons and positively charged hydrogen ions combine with oxygen to form water, which flows out of the cell.

Phosphoric acid fuel cells use liquid phosphoric acid as an electrolyte—the acid is contained in a Teflon-bonded silicon carbide matrix—and porous carbon electrodes containing a platinum catalyst. The chemical reactions that take place in the cell are shown in the diagram.

The phosphoric acid fuel cell (PAFC) is considered the "first generation" of modern fuel cells. It is one of the most mature cell types and the first to be used commercially, with over 200 units currently in use. This type of fuel cell is typically used for stationary power generation, but some PAFCs have been used to power large vehicles such as city buses.

PAFCs are more tolerant of impurities in fossil fuels that have been reformed into hydrogen than PEM cells, which are easily "poisoned" by carbon monoxide—carbon monoxide binds to the platinum catalyst at the anode, decreasing the fuel cell's efficiency.
They are 85 percent efficient when used for the co-generation of electricity and heat, but less efficient at generating electricity alone (37 to 42 percent). This is only slightly more efficient than combustion-based power plants, which typically operate at 33 to 35 percent efficiency.

PAFCs are also less powerful than other fuel cells, given the same weight and volume. As a result, these fuel cells are typically large and heavy. PAFCs are also expensive. Like PEM fuel cells, PAFCs require an expensive platinum catalyst, which raises the cost of the fuel cell.

A typical phosphoric acid fuel cell costs between $4,000 and $4,500 per kilowatt to operate.



Fuel Cell Application

The Quantum Aggressor

The Quantum Aggressor is a Fuel cell powered Hybrid. An AMV - Alternative Mobility Vehicle built for Stealth.


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