[kazoocruiser]

Thanks for the picture. You can get a pigtail to replace the wire that is burned, or splice a wire in with a new eyelet for the alternator post. The wire that is broken / burned open is the charge wire for the battery. From the looks of it, corrosion inside the wire caused too much resistance, causing heat to burn it up.

Disconnect your battery cable before you work on that wire. It carries arky-sparky amperage.