meddlingfool wrote:
Nothing to lose right?
Only your house if you start a battery fire
I have done this with radio control lipo batteries. It's a bit nerve wracking because those things combust much more easily than the li-ion cells used in tool batteries. I use a resistor to make sure the current stays below 1 amp or so. But a skinny steel twist tie wire probably has enough resistance by itself to prevent excessive current and heating of the donor battery.Don't charge it unattended afterward. Over-discharge can damage lithium batteries, which is why the charger won't touch it until you've erased the evidence. One advantage of lipos is that they puff up before exploding, so you can keep an eye on them and pull the plug. Not sure if tool batteries give any warning, I'm not as well educated on their behavior.