M3Armand

As I am storing my summer cars for the winter, I was wondering... With the supposed high "C" ratings of Lipos nowadays, has anyone tried starting their real car with a 4S Lipo battery?

AreCee

iTrader: (1)

Let's see. The typical full size car battery has a cranking amp capaity of 400+.

A 4S lipo has 5 amps. It may last a couple of seconds but won't turn over the engine too much.

Fastburn

iTrader: (18)

we have used them to boost batteries on cars that wont start.

Works like a charm

academygaz

http://www.bigsquidrc.com/rc-myths-f...-car-starting/

Yep, it works.

M3Armand

In the video, they used a 3S = 11.1 volts. After the car started, the alternator overcharged the Lipo = not good. This is why I made the post as 4S = 14.8 volts.

But this is darn good news since "in a bind", all we really need is a "jump" on an almost dead battery. We would just have to use two 2S's in series to avoid the alternator overcharging issue...

HarryLeach

You're confusing current [instantaneous amperage] with capacity [amp hours].

Most Lead Acid car batteries are rated by their Cranking Amps [close to constant C ratings for LiPo] and CCA, Cold Cranking Amps [Burst C ratings for LiPo].

So yes, a 5000mAh LiPo [as low as a 20c constant rated battery will work on a passenger car, may want more for a larger engine/starter] will jump start a car, seen it happen, and as others in this thread have mentioned, it's better to use a 4s to protect the LiPo than a 3s.