I do know if this was talked about yet but this is what happen to me.
I was driving down the road at 55 mph in my 6 volt 1954 Chevy panel 3 speed truck.
All of a sudden out of no where the truck just died.
I pulled over and shut off the key.
Then I switched the key back on, gas and amp gauge needles went in reverse.
I pushed the floor starter button, and the engine barely turned over.
A passer by stopped and we jumped the battery and the engine barely turned over.
I was not far from a small town so the passer by pushed me to a gas station.
The mechanic came out and he was stumped.
I crawled up under the passenger side of the truck, were the battery is located.
At first I didn't notice anything out of ordinary, then I looked up and bingo.
The positive side battery cable sheath had worn thru and the battery cable had welded itself to the frame.
A DEAD short.
I pulled the battery cable from the frame and taped it up.
By now the battery was pretty much cooked from all that welding.
The gas station mechanic had a wrecker with a nice 4 wood plank front bumper, with cut up rubber tires bolted to the wood planks.
That mechanic pushed me from one end of that small town to the other end at a high speed, then she finally fired up.
I stuck my hand out the window to wave off the mechanic and say thanks and kept going.
After another 40 miles I drove in the driveway and right when I did the generator and voltage regulator died.
Check to see if your positive battery cable is grounding out on the body or frame.
Or any hot lead. Mice like chewing on Sheath.