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Starting a real car with a 4s Lipo

Starting a real car with a 4s Lipo

Old 12-29-2010, 11:19 AM
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Default Starting a real car with a 4s Lipo

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?
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Old 12-29-2010, 11:24 AM
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Originally Posted by M3Armand View Post
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?
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.
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Old 12-29-2010, 11:57 AM
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we have used them to boost batteries on cars that wont start.

Works like a charm
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Old 12-29-2010, 12:43 PM
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http://www.bigsquidrc.com/rc-myths-f...-car-starting/

Yep, it works.
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Old 12-29-2010, 12:52 PM
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Originally Posted by academygaz View Post
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...
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Old 12-29-2010, 01:52 PM
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Originally Posted by AreCee View Post
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.
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.
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