20V Max 6.0Ah Lithium Ion Battery

This is a 20V Max 6.0Ah lithium ion replacement battery. It features a durable black and orange housing. Dimensions are approximately 4.5" x 3" x 2.5" (11.4cm x 7.6cm x 6.4cm).It works with DeWalt, but it stopped working. I don't know what's wrong with it.If you know how to repair it then I will give you the battery for you for