Electronics - Voltage and Current - Discussion

Fuel cells and batteries are similar because they use a chemical reaction to provide electricity. A battery stores the chemical reactants, usually metal compounds like lithium, zinc or manganese. Once used up, you must recharge or throw away the battery. A fuel cell actually creates electricity through reactants (hydrogen and oxygen) stored externally. The fuel cell will produce electricity as long as it has a fuel supply. In short, a fuel cell vehicle is refueled instead of recharged.

1) Discharging - Battery cell consist of chemical Reaction in which H2SO4 is converted to H2O and negative ions are released in this reaction. These negative ions nothing but electrons. When total conversion takes place we can say battery is discharged.

2) Charging - In charging process again chemical reaction takes place. In which H2O is again converted to the H2SO4.

A fuel cell is an electrochemical device that contains two electrodes (an anode and cathode) and an electrolyte; it uses a chemical reaction to produce electricity much like a battery. However, unlike a battery, a fuel cell never "goes dead" and never needs recharging. It will continue to produce power as long as it has a constant supply of fuel and oxygen.

The key difference between a battery and a fuel cell is that a battery runs down as the electrodes dissolve, but a fuel cell operates for as long as oxygen and hydrogen flow. The battery is an energy storage device. It stores its fuel internally. A fuel cell is an energy conversion device. Its fuel is supplied externally.

Its exact explanation is battery is close loop means it has two terminal current starts flow from + to - terminal where in fuel cell we put the fuel and it produce energy to run the rotor of generator and electricity produce so fuel does not take part directly in current production like battery hence it is open loop.

Hai @Shaik. I have doubt electrical generator mean? you said electrical generator converts chemical energy to electrical energy. What about battery? electrical generator convert mechanical to electrical.

Fuel cells convert chemical energy into mechanical energy and into electrical energy. Battery cells convert chemical energy into electrical energy.

Fuel cell takes hydrogen and oxygen on anode and cathode respectively and convert this chemical energy into electrical energy.

In battery, mass may not be transfer (closed system) but in fuel cell, mass flow in and out of the system, mean open system.

In battery reduction and oxidation takes place at anode and cathode. Then why the ans is not (b).