[Mattwelds]

I just got a mild miles zx40st for free on Craigslist with no batteries. Can i just buy 6 car batteries and drop them in there? Do i need to source a special battery for lev use? I know AGM batteries came in it originally but are they necessary?
Thanks for any help

 

[piotrsko]

Car batteries work but not generally very long. Deep cycle storage have been the traditional way but only last a couple of years and are really expensive. To play with the concept just about anything of the correct size and voltage will work for a while, but better results are with a lithium pack

 

[Mattwelds]

Car batteries work but not generally very long. Deep cycle storage have been the traditional way but only last a couple of years and are really expensive. To play with the concept just about anything of the correct size and voltage will work for a while, but better results are with a lithium pack

Thanks for the reply Piotrsko.
Is there any other mods that need to happen for lithium batteries? I know i can't just throw lithium batteries into my electric rc car without frying the esc. I'm thinking anything with an esc would be the same.

 

[Mattwelds]

Can the Curtis controller be modded to handle lithium power?

 

[piotrsko]

Lead acid and lithium are mostly interchangeable EXCEPT FOR: lithium is fussy on end of charge voltages and low limits. In other words you get problems going over the per cell maximum voltages like out gassing and fires. My Volt pack outgasses at 4.2v per cell (199v) not good for cell life. Exceeding Low limits cause swelling and power degradation but mostly way out of balance cells which eventually kills the pack.

There's more to it than this, notice I didn't do BMS's?

The advantages to lithium: more cycles, lighter weight, higher energy density, higher circuit currents for a longer time

Your curtis can be reprogrammed to deal with the voltage limits, otherwise DC is DC until you let the smoke out. For a trial run, being very careful, you could interchange packs with no setting differences.

THIS isnt everything you need to know.

 

[lawrencerhodes]

You could drop in car batteries and be sorely disappointed. Lithium is getting really inexpensive. In some cases twice the capacity for the same price as lead. Look at battery hookup and look for used batteries on this list and other EV forums. Sometimes 72v modules can fit and of course can be put in parallel. Make sure you have the 72 or 48v version. Of course these will never reach freeway speed. It is illegal to so modify