My Battery light comes on when i drive in a puddle and its raining. What's Causing this? What do i need to fix?

My Battery light comes on when i drive in a puddle and its raining. What's Causing this? What do i need to fix?

Added (1). i have a 2004 Honda Accord EX-L 4 Cyl.

I don't know how the belt is tightened on your vehicle, but it's too loose, and may be worn past use. Get a new belt.

Agreeing with M; a splash of water is making your alternator drive belt slip. You may need an adjustment, a new belt, and or a new belt tensioner. Not terribly expensive.