Milwaukee M18 Jump Start Truck?

[@patientprepper2030]

Was going to buy an expensive jump starter. might just use this method. will put some aligator clips on and a diode for back flow protection. thanks for the idea.

[@Originalcoffin]

I like the diode idea.

[@Eighty8Fitter]

Dude exactly my thought, I have the M18 battery pigtail adapter and this is a genius idea!

[@michaelkish7526]

I love Milwaukee anything both in quality and service. I hope they never degrade in both like so many have over the years for the sake of profit.

[@mwils51]

I was searching for this because it just happened to me this morning. Forgot to turn off my inverter on truck last night and dead battery this morning. No worries about the Milwaukee M18 being 18V and the truck 12V?

[@philipdove1705]

I wonder if that causes damage to the m18 battery

[@americantemperaturecontrol7852]

I've had no problems with any Milwaukee m18 battery afterwards. I had a weak truck battery for a couple months so I've had to jump it at least a dozen times.

[@foogod4237]

This is actually fairly dangerous. You should be very careful when doing this that you don't let those two wires touch each other (and you don't connect it up backwards). If they do, your M18 battery will likely fairly quickly turn into a Presto Log instant fire starter inside your engine compartment (or in your hand!). Depending on how dead your car battery is, just leaving the M18 connected to it for too long might actually cause a fire as well. Also, even if it doesn't catch on fire, if your M18 is fully charged and you leave it connected too long you could very possibly end up damaging your car battery, as they're not really designed to have more than about 14V applied to them, and charging them with voltages over that can lead to excessive gas buildup inside the battery, etc... Also, depending on the electronics in the vehicle, applying 18V to the vehicles electrical system could possibly damage more sensitive electronics in your car like your stereo system, navigation system, etc. Real battery-powered jump starters have batteries designed for this purpose, and extra protection/regulation circuitry for exactly these reasons. This is a clever hack that may technically work if you suddenly find yourself with no other options, but it's really better to have a proper battery-powered jump-starter instead. Doing things this way is just playing with fire (actually literally).

[@Mario-uo2zu]

So someone could build one with a voltage regulator?

[@foogod4237]

@@Mario-uo2zu A voltage regulator (and some protection circuitry) would definitely make things better, but one of the other problems is that we're talking about needing really pretty large currents here, so you'd actually need a pretty heavy-duty custom-designed regulator to handle it without being fried itself. (And if you're going to get into that level of engineering, it's probably easier (and maybe even cheaper) to just buy one of those portable battery charger/starter things instead anyway.) This hack might be useful if you don't have anything else to work with (and you're OK with the risks), but if you're actually planning for this sort of eventuality ahead of time, realistically, there are other options which are pretty much always going to be better approaches, I think.