Direct formic acid fuel cell performing real time measurement and control of concentration of formic acid and operation method thereof

A method of operating a direct formic acid fuel cell, comprising:

• measuring in real time a concentration of a portion of formic acid to be provided to an anode before the formic acid is provided to the anode (S1);
• and
• comparing the measured concentration value with a predetermined concentration range, controlling in real time the concentration of formic acid to be supplied to the anode depending upon the real time measurement in such a manner that the measured concentration value does not deviate from the predetermined concentration range, and providing the anode with the formic acid (S2).