Why phosphoric acid is used in fuel cell?

Phosphoric acid has many attractive properties as a fuel cell electrolyte such as (1) stability, even at 200 °C; (2) low vapor pressure, although not negligible; (3) ability to use air as the cathode reactant gas; and (4) tolerance to carbon monoxide (200 °C operation).

Which electrolyte is used in methanol oxygen fuel cell?

These cells use platinum-based catalysts to promote the electrode reactions, and a solid acidic proton conducting polymer electrolyte, often Du Pont’s Nafion® perfluorinated sulphonic acid-type materials. However, the present PEMFC powered vehicles are almost exclusively based on the use of pure hydrogen as the fuel.

Why phosphoric acid fuel cell PAFC is unsuitable for use in cars?

If gasoline is used, the sulfur must be removed. At lower temperatures phosphoric acid is a poor ionic conductor, and CO poisoning of the platinum electro-catalyst in the anode becomes severe.

Which electrolyte is suitable for alkaline fuel cells?

potassium hydroxide
Alkaline fuel cells These fuel cells use a solution of potassium hydroxide in water as the electrolyte and can use a variety of non-precious metals as a catalyst at the anode and cathode. In recent years, novel AFCs that use a polymer membrane as the electrolyte have been developed.

Which type of electrolyte is required for phosphoric acid type fuel cell operation?

Phosphoric acid fuel cells (PAFCs) use an electrolyte composed by concentrated phosphoric acid (H3PO4) dispersed in a silicon carbide matrix. The electrodes are composed by dispersed platinum particles on a porous graphitic substrate [15].

How do methanol fuel cells work?

It has an anode and a cathode. They are separated by a membrane. By means of an electrochemical reaction, the direct methanol fuel cell converts the fuel, i.e. methanol, into electricity in combination with oxygen. A heat engine drives a generator and thus makes the electricity usable.

What is a fuel cell explain the working of methanol oxygen fuel cell?

In a fuel cell electrical energy is obtained from oxygen and a fuel that can be oxidised The essential process in a fuel cell is Fuel + Oxygen → Oxidation product +Electricity Methanol – oxygen fuel cell are powered by pure methanol. Fuel cells of this type were now called “direct-methanol fuel cells” (DMFC).

Why is methanol fuel cell better than hydrogen fuel cell?

The fuel cell converts the reformate gas into electricity powering the electric motors. Compared to hydrogen-powered fuel cells, a methanol fuel cell system eliminates some of the difficult challenges linked to handling and distribution, infrastructure investments, and low volumetric energy density.

Can phosphoric acid fuel cells PAFC be used in buses?

Phosphoric Acid Fuel Cells☆ PAFCs were traditionally made for stationary applications with output power ranging from 100 to 400 kW but are now finding use in mobile applications like buses, trains and even submarines.

Which electrolyte is used in an alkaline fuel cell Brainly?

Alkali fuel cells operate on compressed hydrogen and oxygen. They generally use a solution of potassium hydroxide (chemically, KOH) in water as their electrolyte. Efficiency is about 70 percent, and operating temperature is 150 to 200 degrees C, (about 300 to 400 degrees F).

Is phosphoric acid a strong electrolyte?

HC2H3O2 (acetic acid), H2CO3 (carbonic acid), NH3 (ammonia), and H3PO4 (phosphoric acid) are all examples of weak electrolytes. Weak acids and weak bases are weak electrolytes. In contrast, strong acids, strong bases, and salts are strong electrolytes.

Can phosphoric acid be used as a fuel cell electrolyte?

Phosphoric acid has many attractive properties as a fuel cell electrolyte such as (1) stability, even at 200 °C; (2) low vapor pressure, although not negligible; (3) ability to use air as the cathode reactant gas; and (4) tolerance to carbon monoxide (200 °C operation).

What is the electrolyte in a fuel cell?

Electrolyte. The two electrodes are separated by a porous matrix saturated with an aqueous alkaline solution, such as potassium hydroxide (KOH). Aqueous alkaline solutions do not reject carbon dioxide (CO 2) so the fuel cell can become “poisoned” through the conversion of KOH to potassium carbonate (K 2 CO 3 ).

What are the disadvantages of using potassium hydroxide as an electrolyte?

Operating with potassium hydroxide as the electrolyte requires a very clean hydrogen source and bottled oxygen (or carbon dioxide scrubber) as the fuel and oxidant, respectively, which is a very major disadvantage for backup power application as it significantly increases operational costs.

What is the concentration of phosphoric acid in PAFC?

If the reactant flow rate is increased, the electrolyte becomes more concentrated, and the water vapor pressure is decreased to maintain the water balance and vice versa. The concentration of phosphoric acid is usually around 100 wt\% when the phosphoric acid fuel cell (PAFC) is operated at 200 °C.