Electrical Power: All-or-nothing Intermittency Causes??

I believe I may have fried the battery, while considering alternative mount options for the winch control box...and, possibly, shorting the cable(s)... Yes, I should have been much more conscious and aware, etc... Was totally dead the next morning, charged the battery... Now: I haven't been able to test the battery acid, etc., to determine the internal state but, starts and runs, on/off a few times, then will be absolutely dead...with no power even to run the dome light.. I'll be putting in an Optima, as intended anyway, and will determine the actual state of current battery...as well as checking alternator/charging circuit, etc., but...want to ask if anyone is aware of any component(s) that could, if faulty, cause an intermittent and total power-on/power-off condition, electrical-system-wide?? I'm guessing no, but am fairly new to the XJ, and thought it worthwhile asking....

Thanks, indeed, for info and insights!

Mine did the same thing, i ended up replacing the fusible links on the starter solenoid with a fusible link panel from a honda civic, no more problems, and bonus- easily replaceable fusible links in a nice mountable package. Next time it dies, check the turn signals, hazards, wipers, and running lights, i don't recall which one it was, but one of those was still working while everything else was dead.

Intermittent loss of all voltage sounds like either a corroded battery cable, bad ground, or more likely a battery with an intermittently open cell.

Turned out to be, in fact, a deteriorated ground connection...particularly, strap engine-to-firewall... Can't forget the importance of the other side of the circuit, indeed...

Thanks much for the mention of the ground as a suspect quantity... ----Was gonna get an an Optima, anyway...