Replacing Insight 12v pb battery with a supercapacitor!

[retepsnikrep]

Any thoughts on this. I have a couple of Insights, and an EV in which I use a Maxwell supercapacitor as the auxiliary 12v battery, it is charged from a DC-DC converter off the main pack like the Insight one.

I am tempted to fork out for one to experiment.

I see no reason apart from ah and cost/capacity why it should not be replaced. Does anyone know what the static drain is on the pb battery when vehicle is off and locked? Is there any?

A link here.

http://www.maxwell.com/ultracapacitors/ ... heets.html

Peter UK

I realise it is not a particulary sensible idea!

[b1shmu63]

I tried something like that on a motorcycle a long time ago. It didn't have an electric starter. It worked but the engine would stall if I turned on the lights and blew the horn!

The supercaps would have to be overkill sized to crank over the engine at 25 below here in Canada. You wouldn't want to short those beasts out when giving someone a boost either.

Practical considerations asside it would give you better mileage, though perhaps not enough to measure. Great idea for the EV though. Shows you are thinking outside the box.

[Double-Trinity]

I tried something like that on a motorcycle a long time ago. It didn't have an electric starter. It worked but the engine would stall if I turned on the lights and blew the horn! Bad Grin

The supercaps would have to be overkill sized to crank over the engine at 25 below here in Canada. You wouldn't want to short those beasts out when giving someone a boost either. Wink

Seems like the best solution to that would be to wire a smaller battery in parallel with the ultracaps. The ultracaps could handle the fluctuation caused by lights, rolling windows down, etc. while the battery would be there for more powerful surges, such as starting. The total combo could also weigh significantly less than a full-sized battery, as well (especially if the battery brackets etc. were replaced with smaller ones)

[Dougie]

I don't remember any discussion here about how much smaller the 12V battery could be made. If you never use the starter motor, why can't it be much, much smaller?

[Eli]

This is an old thread, but I like the idea and thought about trying it myself. Maybe I will?

I have a 433 Farad, 15V supercap bank begging to be put to use.

433F @ 15V is about 1.8Ah. I am not sure if that would even get me through a night with the parasitic draw of the car, though..... Probably quite impractical. But it's still fun to tinker.