Battery Replacement, Lead to Lithium?

I have recently purchased a moto tec off road E-board however i didnt realize the battery was a lead acid until it arrived. (should have read more into i guess) Anyways i was curious if it was possible to switch it from a lead acid to a lithium. The lead battery has an output of 36v with 14ah and the motors are both 800w requiring 36v and a rated current of 28.5A (there are 2 of them) Basically what i am asking is if anyone knows a lithium battery that will work with this set up? Heres a link to the motors/speed controller

36V equals 10s lithium batt. So get for example 2x 5s Lipos. Connect them in series and you´re good to go. You could also take 5x 2s Lipos

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Im kind of new to this if you cant already tell, would i just go higher in the number of cells to make the range of the board longer or would i have to just stay with 10s and go higher in the mah? as of now this board only has a range of 10 miles.

this is an inrunner motor, so not really efficient for an eskate and if you start replacing parts, you end up better getting rid of that thing and building your own :wink: If thats and 36V ESC you have to stay with 10s and put more cells in parallel to add mah, just do a bit research here

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@TarzanHBK 10s Li-ion or Lipo is not 36v It’s 42v at full charge. Lifepo4 cells would probably work since they are 3.65v at full charge.

The lead battery is 36V nominal too, so no problem in using a 10s lipo here

the lipo’s weigh substantially less then the lead acid correct? Thats my main concern with this is to get the weight and charge time down. Right now it takes a good 6 hours to charge this battery.

Fully charge your Lead Acid battery with its designated charger and check its voltage just to be on the safe side. If it charges up to at least 42v then your good to go with Lipos.

I would have to run to the store and grab a voltage meter. However for the time being i did find out its not 1 battery but 3 in series.

3 12v batteries in series. You might be able to find out by the charger. If it has input and output info printed on it. the output voltage will be your battery’s full charge voltage.

Input:100-240VAC,50/60Hz 1.5A Output: DC+36V/2A

This is what I suspected, your battery is only going to be 36v at full charge. So your system is designed for 36v. If you go higher i.e.: 10s Lipo or Li-ion, 42v, there is a possibility that you could damage the system and then it won’t work at all. You could put a couple 4s Lipos in series which would give you 33.6v at full. You will have some performance loss and you would need a balance hobby charger to charge them. And this might not work either if there is a battery management system built in to the electronics because it would be designed for the 36v lead acid batteries.

He could go with less voltage, lose a bit of speed but increase the range compared to the Lead acid batteries

The range with the lead acid battery is 10 miles. Not bad really. The total weight of the board is 71 lbs Which is really heavy. Looking at the batteries, I don’t see any type of wiring for a management system so that is probably not an issue.

So a 8s battery would give more range, less speed (But the board will be lighter, so maybe, more speed). But it, maybe, don’t work well, because the potentiometer is for 36v (I mean, it maybe uses Duty Cycle, so the voltage is relevant), so 8s or 10s will get it crazy, right?

10s 42v might burn the circuits out. No way to be sure. He could try 8s 33.6. Like you said, the lighter weight might make up for the loss of voltage.

Two of these might do it.

Is there some sort of management system i could get to run the 10s lipos but run it through a resistor of some sort to get it back to 36v?

I think some mosfets could do it, but go with 8s, is cheaper and the chargers are cheaper

No but you could get a 10s battery pack made of lifepo4 cells that would be 36.5v at full charge together with a BMS and then you could use a simple charger like the one you already have. @barajabali is a lithium battery maker who could probably help you with that. The Lifepo4, also known as A123 cells are also high amp output so they work well with e-boards.

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