Just thought I'd add a clip of jump starting my Mini with a modern LiPo battery
I've had a Jump Start pack for years but the old lead acid battery inside was long dead and has been sat in the corner of the garage for ages.
I have lots of modern type LiPo batteries from various RC cars and Quadcopters and know that these batteries can pack quite a punch.
I had a couple of spare quadcopter 4S LiPos, that means they have 4 cells in series, each cell is approx. 3.7 volts so 3.7 x 4= 14.8 volts. The battery also has a 35C discharge rate so basically it can discharge at it's Ah rating x35 for about ten seconds. The battery is a 5000 mah pack, so 5 x 35= 175 Amps.
I removed the old lead acid battery from the jump pack and made up a battery connector for the LiPo battery which was basically just a female connector with two ring terminals soldered onto it and bolted this directly to the ring terminals on the ends of the jump leads.
The Lipo battery weighs approx. 500 grams whereas the original lead acid battery was about 3kg
There are also videos showing people doing the same with 3S LiPo's, these have a voltage of 11.1 Volts
A few words of warning for anyone attempting to do this
1. You need a specific charger for charging LiPo batteries.
2. Disconnect the jump pack from the car battery as soon as the car starts, don't leave it connected as this will damage the LiPo battery and it could set on fire.
3. I'd only use this method on a car with just a flat battery, I wouldn't attempt starting a car that has other starting issues.
Edited by MR J, 24 March 2018 - 03:49 PM.
