GoPed ESR750EX SLA to LIPO conversion question

[777]

How can I convert from SLA to LIPO? I tried searching up this forum about it but only came up with a few answers. Can someone please help me with a link or something.

I know this is such a NOOB question but I really am having a hard time finding out how to do this conversion.

I have a completely bone stock GoPed ESR750EX (SLA) and will be using it to commute to work (about 4 miles round trip)

Anything would help.

Thanks in advanced!

 

[dirkdiggler]

If you want the performance to be similar, but lighter use 6s(24v) lipo batteries. Your SLA batteries are 9ah, so if you need range you want to buy 2 6s batteries of 5000mah. Run this in parallel and you'll get a 24v 10ah lipo battery.
If you want to increase your speed you can likely get away with a 36v battery setup. You could do two 4s batteries to be on the conservative side, and they are sometimes cheaper. Or you can risk two 5s batteries and see how long your controller lasts. You have to be careful about overvolting, because the controller will no longer shut off when the voltage gets too low. This is solve by a voltage alarm that hooks to the battery to let you know when to stop. You'll kill the battery if you drain it too low.
Hope that helps.

 

[scoot]

unfortunately there really are no drop in (plug & play) lipos that I am aware of. Goped uses two to four 7s Lipo packs custom built from Battery Space... each pack has its own beefy full featured BMS. For a while (a year or more ago) you could get the packs and BMSs seperatly from Battery Space (very expensive) and hook them togther if you knew what you were doing... could get pretty dangerous if you didn't though.

BTW, the ESR controller maxes out at 32 volts, so 7s Lipo or almost 9s Life is the highest you can hope to use. 6s DIY Lipo has been used successfully

 

[silviasol]

I just am about finished with my esr750 upgrade, see my post
http://endless-sphere.com/forums/viewtopic.php?f=35&t=58064

Stock goped lipo packs are here, $70 cheaper then at goped.com
http://www.batteryspace.com/Custom-Polymer-Li-Ion-Rechargeable-Battery-25.9V-8Ah-207.2wh-90A-rate.aspx
Not really worth it pricewise but it has a pcm/bms built in.

 

[z50king]

The stock controller will only allow around 30 volts max. We run 7 cell lipo packs all the time. Hard part about 7 cell is charging and balancing. It is much easier to find chargers and balancers for 6 cell packs. I'm running 4 6 cell packs in parallel with good results. Packs are few years old now and are lacking in range

 

[stian222]

I'm a noob as well and have a SLA extended range Hoverboard that I was hoping to upgrade easily. Because I'm not super techy I went and purchased 4 of these puppies and crossed my fingers.
http://www.amazon.com/StarkPower-Lithium-Phosphate-Battery-LiFePO/dp/B009GMQCO6
I was so pysched about the ease of swapping and the light weight but...I knew it was too good to be that easy. It seems that the onboard charger isn't up to the job. I tried three times with similar results. Flux capacitor says full charge but when I take it out on the street I only get about two blocks or so before it's flashing red and I'm walking it home. Any suggestions for onboard or external charger mods would be most welcome. I don't know for sure but I feel like it's not the batteries that are at fault. Cheers

UPDATE 10/20/14:
Sorry it took me forever to get around to sharing my findings.
A private message from Sloped asking for an update prompted the reply below.

So it turns out that the batteries were fully charged but their internal BMSs were switching them off cause I always ride in turbo mode and they couldn't handle the draw. So I trained myself to only ride in 'econo' mode and they work like a charm. It was hard at first cause I ride in Manhattan and like as much speed as possible but eventually I gave in to the slow side. I had to put tape on the switch to ween myself. The onboard charger works just fine for these batteries too.
I contacted the company and talked to a very nice gentleman, who I think is an engineer, about the market available from GoPed owners. He's looking into it but I don't think we'll see them any time soon. It would be so easy for them too. All they have to do is change a setting on the BMS and bobs your uncle, or at least that's what my not so techy brain is telling me anyway.
I think I'll have to suck it up and make my own setup to get my speed back. Anyways, I hope this helps. Cheers, Stian

 

[silviasol]

The stock controller will only allow around 30 volts max. We run 7 cell lipo packs all the time. Hard part about 7 cell is charging and balancing. It is much easier to find chargers and balancers for 6 cell packs. I'm running 4 6 cell packs in parallel with good results. Packs are few years old now and are lacking in range

When the controller shuts down at it's low voltage shut off point what voltage are your 6s packs at?

 

[z50king]

The stock controller will only allow around 30 volts max. We run 7 cell lipo packs all the time. Hard part about 7 cell is charging and balancing. It is much easier to find chargers and balancers for 6 cell packs. I'm running 4 6 cell packs in parallel with good results. Packs are few years old now and are lacking in range

When the controller shuts down at it's low voltage shut off point what voltage are your 6s packs at?

I have only ridden my packs down to 3.75 volts. I have never had to push them farther. The controller will shut off around 18-19 volts depending on what it was set it. You can change this with a GoProgrammer but they are nearly impossible to find these days

 

[Silenthunter]

If the speed controller is programmable and works accurately then I don't see the need of the BMS or PMC. An RC charger can do all balancing and charging. I would install a cell meter as a back up just in case some cells die or go out of balance.

 

[silviasol]

The stock controller will only allow around 30 volts max. We run 7 cell lipo packs all the time. Hard part about 7 cell is charging and balancing. It is much easier to find chargers and balancers for 6 cell packs. I'm running 4 6 cell packs in parallel with good results. Packs are few years old now and are lacking in range

When the controller shuts down at it's low voltage shut off point what voltage are your 6s packs at?

I have only ridden my packs down to 3.75 volts. I have never had to push them farther. The controller will shut off around 18-19 volts depending on what it was set it. You can change this with a GoProgrammer but they are nearly impossible to find these days

Ok so 3v a cell, not too bad. I made a backup 13ah 6s pack without bms to charge on my b6ac out of extra cells I had to use on my esr with sla controller for short runs.

 

[SloPed]

I'm a noob as well and have a SLA extended range Hoverboard that I was hoping to upgrade easily. Because I'm not super techy I went and purchased 4 of these puppies and crossed my fingers.
http://www.amazon.com/StarkPower-Lithium-Phosphate-Battery-LiFePO/dp/B009GMQCO6
I was so pysched about the ease of swapping and the light weight but...I knew it was too good to be that easy. It seems that the onboard charger isn't up to the job. I tried three times with similar results. Flux capacitor says full charge but when I take it out on the street I only get about two blocks or so before it's flashing red and I'm walking it home. Any suggestions for onboard or external charger mods would be most welcome. I don't know for sure but I feel like it's not the batteries that are at fault. Cheers

Does anyone know the answer to this?

Need to replace my SLAs and wanted an easy route like this vs building out a custom lipo kit.

Just wanted best plug n play option for 200 or less

Thanks!!!!

 

[stian222]

This looks like the answer we've been looking for. http://www.amazon.com/Phosphate-K2B12V10EB-K2B12V10E-K2B12V10-ET-Life-P-1210/dp/B00N59CQHS
I'm gonna buy four of them soonish and let you know my results. If anyone beats me to it please post details here. Cheers

 

[silviasol]

This looks like the answer we've been looking for. http://www.amazon.com/Phosphate-K2B12V10EB-K2B12V10E-K2B12V10-ET-Life-P-1210/dp/B00N59CQHS
I'm gonna buy four of them soonish and let you know my results. If anyone beats me to it please post details here. Cheers

See the Q&A at the bottom
Q: What is the max discharge rate?
A:Max. cont. current 20A Max. 30sec. pulse 30A With a cut-off voltage 8.0V Battery Buys 800-790-9941

You would need 4 batteries for it to work and that would be only 40amp continuous current and 60amp max 30 second. That is enough but pushing it. Also is that 10ah rating to match an SLA cell amp rating? SLA amp hour only about half the amount of lithium so in reality it could be only a 5ah lifepo4 pack. Headways would be much cheaper.