Hi Nagesh,

Electrochemistry - Electrochemistry is a branch of chemistry that deals with  the relation between Chemical energy and Electrical Energy.

To be exact - Suppose a chemical reaction is going in a cell -- Generating Some amount of heat (Chemical enegry) that furthur Convert in  an electrical enegry that you can use it later   

You can refer our notes here - https://www.learnohub.com/revise-notes/Class-12/Chemistry/Electrochemistry/1/62873ebf53790e1ac4208a76

Hope you got your answer

Thanks for Asking