esr750ex battery upgrade and oneway gearing for freewheeling?

[Duc1098]

Hi all,

I've aquired a second hand esr750ex and its great apart from the range. Also this esr750 needs better free wheeling. My old china made electric scooter had oneway gearing which allows better freewheeling. Is there any one way gearing sprockets that will work on the esr750? Surely I'd save a lot of battery power with a freewheeling feature.

Also what sort of capacity can I upgrade the batteries too? 12-20amp or more? I dont mind raising the deck height a little for the upgrade.

What effects will the battery upgrade cause? Heat issue's in the motor? I dont plan to run it in turbo full time, Mostly eco mode is good enough for me, Just use the turbo mode for those steep hills.

Thanks

[JRDELUNAIII]

Hi all,

I've aquired a second hand esr750ex and its great apart from the range. Also this esr750 needs better free wheeling. My old china made electric scooter had oneway gearing which allows better freewheeling. Is there any one way gearing sprockets that will work on the esr750? Surely I'd save a lot of battery power with a freewheeling feature.

Also what sort of capacity can I upgrade the batteries too? 12-20amp or more? I dont mind raising the deck height a little for the upgrade.

What effects will the battery upgrade cause? Heat issue's in the motor? I dont plan to run it in turbo full time, Mostly eco mode is good enough for me, Just use the turbo mode for those steep hills.

Thanks



I ordered my ESR750EX and it should be arriving to me this Tuesday. In the near future I am thinking of replacing the 4 - 9AH SLA batteries with a Lithium Ion Battery. I am thinking of getting 2 - 10AH ones for a total of 20AH. Now some will say that the original 4-9AH SLA batteries gave a total of 18AH so there will only be a slight increase in range, but they did not take in effect that SLA batteries have peukert effect which is basically the higher current used will diminish the actual capacity of the SLA batteries. So in theory, those 18AH will only give about 75% or less than the actual rated capacity, so about 13.5AH or less. Whereas the lithium batteries do not really suffer from the peukert effect. Plus with the slight increase of voltage from the Lithium batteries, top speed will inscrease slightly as fully charged they are at 29+ volts right under the ESR controllers cutoff.

Also does anyone know if this freewheel will work with the ESR's ??? Thanks for any info. God Bless :)

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=3327


http://www.electricscooterparts.com/images/SPR-SB4HA.jpg

[PatmontS]

I ordered my ESR750EX and it should be arriving to me this Tuesday. In the near future I am thinking of replacing the 4 - 9AH SLA batteries with a Lithium Ion Battery. I am thinking of getting 2 - 10AH ones for a total of 20AH. Now some will say that the original 4-9AH SLA batteries gave a total of 18AH so there will only be a slight increase in range, but they did not take in effect that SLA batteries have peukert effect which is basically the higher current used will diminish the actual capacity of the SLA batteries. So in theory, those 18AH will only give about 75% or less than the actual rated capacity, so about 13.5AH or less. Whereas the lithium batteries do not really suffer from the peukert effect. Plus with the slight increase of voltage from the Lithium batteries, top speed will inscrease slightly as fully charged they are at 29+ volts right under the ESR controllers cutoff.

Also does anyone know if this freewheel will work with the ESR's ??? Thanks for any info. God Bless :)

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=3327


http://www.electricscooterparts.com/images/SPR-SB4HA.jpg

Interesting battery find.
They look like they'll not discharge enough current to accelerate or climb hills like you're used to with the ESR, but certainly adequate to maintain 20 mph on level ground.
The ESR's on-board charger will work fine as is, and those batteries will greatly reduce the overall weight of the ESR with a guestimated range increase of 15-20% over the ESR750EX SLA batteries.
A little pricy, but let us know how they do.
A freewheel set-up would help somehwhat, but the extra cost and effort will be very significant for the less than significant range improvement.

[JRDELUNAIII]

Interesting battery find.
They look like they'll not discharge enough current to accelerate or climb hills like you're used to with the ESR, but certainly adequate to maintain 20 mph on level ground.
The ESR's on-board charger will work fine as is, and those batteries will greatly reduce the overall weight of the ESR with a guestimated range increase of 15-20% over the ESR750EX SLA batteries.
A little pricy, but let us know how they do.
A freewheel set-up would help somehwhat, but the extra cost and effort will be very significant for the less than significant range improvement.


Hi Steve,

Thanks for the comment. One of those single lithium packs says that it will handle 40amps continous, and if you were to put them in parallel like I plan too, 80amps continous. I am thinking that it might be able to do bursts of 100+ amps for a few seconds. I do not have any hills here where I live so I should be fine. That is also good to know that the stock on board charger of the ESR should work with these. Again thanks for making a excellent product, I will keep you updated on how it goes with the batteries. God Bless :)

[Duc1098]

http://www.electricscooterparts.com/images/SPR-SB4HA.jpg

Hi all thanks the help :)

JR, I've got the oneway gearing but initial thoughts are it wont fit right in. I'll need to get my welder mate to help us out a bit. But I'm keen to have it fitted so will let you know in the future.

Those batteries look good. Pricey tho, A little out my range :(

Steve, whats planned for the next esr750 replacement ;). Great product mate the quality is awesome. Cheers

[v tach]

I am thinking that it might be able to do bursts of 100+ amps for a few seconds. The maximum discharge current is limited to 45 amps by an electronic circuit constructed within the pack.

I'm not so sure the difference from the stock SLA batteries would be very dramatic as far as acceleration and hill climbing anyway. The stock SLA batteries lose a lot of their maximum discharge current capability very quickly after a fresh charge and initial use. Two of the Li-Ion Poly packs would likely provide satisfactory results if they are constructed of good quality cells and maintained properly. $800 for batteries though...

[Wimmig]

The maximum discharge current is limited to 45 amps by an electronic circuit constructed within the pack.

I'm not so sure the difference from the stock SLA batteries would be very dramatic as far as acceleration and hill climbing anyway. The stock SLA batteries lose a lot of their maximum discharge current capability very quickly after a fresh charge and initial use. Two of the Li-Ion Poly packs would likely provide satisfactory results if they are constructed of good quality cells and maintained properly. $800 for batteries though...

The flaw with the ESR design lays in it's battery charge circuit, and it's CMID chip which basically works out it's total remaining charge. Up the settings by a few hash marks and you can pull ~ 10% more total power and range out of it.

[PatmontS]

The flaw with the ESR design lays in it's battery charge circuit, and it's CMID chip which basically works out it's total remaining charge. Up the settings by a few hash marks and you can pull ~ 10% more total power and range out of it.

Sorry Wimmig,
The ESR charger is actually one of the most sphisticated "smart chargers" available.
It has several charging level regimins to bring SLA batteries to their maximum capacity and life expectancy. Withought giving away too much information, the initial segment is somewhat "soft" to avoid high current to cold and low charged bateries. Then at a specific charge level, it shifts into quite a high charge rate to about 80% in a fairly short time. The final 20% is charged wth an ever gentler charge rate which is very important for SLA batteries.
Though that is not an ideal regimin for Lithium poly/ion bateries as far as time to charge is concerned, they'll be charge safely to absolute maximum on the ESR, just the same.

[v tach]

Its always a bit of a compromise getting the most performance AND life expectancy from any battery.

If anyone thinks they can get a little more of either from the ESR's stock batteries, you can always charge them yourself. Without the experience and proper knowledge, I'll bet most would end up prematurely needing replacements.