It looks like there's been some shade-tree splicing done right there. Resistance at a splice is a heat source, and the higher the current flow. the higher the heat becomes. Eventually, the insulation melts, the wires corrode, and the joint burns in two. On any main charge lead connections, I'd reccomend either using a single wire without splices, or doing a soldered joint if it's absolutely necessary to connect wires together. I'm partial to the "Western Union splice" that was used on telegraph wires for decades. Strip about 2 inches of insulation off each wire, criscross them at the midpoint of the bare spots, and do a tight wrap in both directions with pliers so there is a very wide point of contact. This makes a splice with virtually no resistance, plus it's so strong the wires will break somewhere other than the splice if subjected to a hard pull. Then solder the joint together with rosin-core solder and cover it with a piece of heat-shrink tubing for a neat-looking, permanent repair.
Jerry
