My battery has some white build-up,very powdery.does this mean that my battery is leaking?(It's not grease)

 

no, just foreign matter corroded the battery...Take a nice hard brissle brush, get baking soda and some water.

Disconnet the Negative!

Mix a tablespoon of baken soda in like 4oz of water, pour a little of the mixture on the terminal that's corroded, it will start foaming, take the brush, and brush it until it is clean. Wipe it down with a towel. Done.

Connect the Negative Back.