engine starter LiPo

[e67]

I need a new car battery.Sub compact size. I would like to do LiPo. Are there any shipped LiPos available that are affordable worth getting? I need it this week shipped.
Of course I will pay more than Lead ....what do you know?

 

[Bobert]

I need a new car battery.Sub compact size. I would like to do LiPo. Are there any shipped LiPos available that are affordable worth getting? I need it this week shipped.
Of course I will pay more than Lead ....what do you know?

Lifepo4 is not a practical choice for an automotive application yet. Usually the cranking amps are to high for the bms on startup and the load on the alternator is to high on recharge and the alternator will burn out prematurely. The charge profile of an automotive alternator is usually incorrect to make the most of the capability of a lifepo4 battery. Other lithium chemistries have similar problems.

 

[e67]

while we are on the subject.... a couple years ago I built a super capacitor battery with 6 Maxwell caps. About 15 volts.
I played with it on the bench for awhile and forgot about it.I was going to try it as a pre start between the batt and the starter but I didn't have a clamp meter to test its in rush current to the starter and was concerned about damaging the starter on a small Toyota 1.5 liter. But I will buy a clamp meter soon. The caps get trickle charged in a few minutes by the lead acid battery.
What amount of current would be too much for the starter.???How about a pick up starter? Its about the size of a small battery so I might use it in a truck later on...there is no room in my Toyota for it unless I ran 10 ft cables...What do you think??