Question

Electrochemical devices are often used for energy storage application .....true or false

Answer 1

yes one is the battery or cell

Answer 2

Yes, some  of electrochemical devices  act as storage of energy, device like capacitor can be used as a storage,  it is disconnected from  circuit and  store energy  in a temporary  way and also help to keep the power supply  constant as batteries  are changed to avoid discharge or overcharging of the batteries thereby avouding loss.