When heat shrinking battery cable it is always best to use an adhesive lined product designed for heavy duty use. By doing so you create a hermetically sealed connection that will allow no water or moisture to corrode or damage the crimped fitting.


You also need to ensure that the adhesive melts out of the ends of the shrunk connection. If you do not see the glue leaking out, as you do in this photo, continue with your heat gun until you do. Remember heat evenly!