Question

why do we need electroplating

Answer 1

it make the cheap object getting good look .it helps to coat iron to prevent it from rust and it is used in battery to save its connectivity

Answer 2

Electroplating is a process where, an electrically conductive surface of an object is deposited with a metal. As the name suggests, this deposition is done by a process aided by flow of electric current. This metal coating completely amd uniformly covers the surface of the object with a thickness of around 3 to 7 microns.
** Electroplating allowes you to put a thin layer of metal on an irregular shaped object. It's not only the way to do this, but it is fairly easy and the capital costs are not too high.