Evo Uberscoot citi 800W to lithium

Kapurnicus

1 µW
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Dec 19, 2016
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Hey guys. Just bought my first electric scooter off craigslist. Everything seems to be pretty well brand new except the battery life (the scooter sat uncharged for most of a year he said). Looks like I'll need to replace the batteries. It's 36v SLA. It seems stupid to spend $100 on bad batteries when I could buy better batteries. Doesn't anyone have lithium suggestions? I'm new to modding a scooter and I'm not sure exactly what I should do or what the best brands are. Please assume I know nothing about the charging and purchasing of these batteries.

I need a 36v battery pack and a charger from what I've read. Any suggestions?

Now..... I'm considering doing 48V, would that be a bad idea? Its an 800w 36v hub motor and I'm not sure where to get another if I fry this one. Parts seem to be scarce.
 
Hi,

first take a picture of the controller. Then we'll see what your options are.

Other Question: Do you already own a RC charger? (which can balance Lipos)
 
Oh man, I don't get emails when someone replies. I'll have to click the checkbox. I thought since it was my thread that would happen automatically.

Thanks for the reply. I haven't opened up the battery compartment yet, but I will soon. The controller should have 60V caps, but I'm not opposed to buying a 48V controller, it was really the hub motor I was worried about. I have some motor knowledge and common sense dictates that as long as I watch the temperature, an increase of 1/3 in power will not do any horrible damage, but I should probably watch it as the motor is bogged down (going up hill) as that makes the most heat.

It is probably safer to stick with a 36V battery, but I know nothing about what type to buy. I do not own a charger (not a li-po charger anyway, just regular 12 volt car chargers). I'm not sure where to begin looking for the best type of battery pack and charger. If i'm going got spend some money I'd like to get something with proven quality.

Thank you so much! I'll post some controller and battery information soon.

Upon further reading I think I want to go with LiFePo4 batteries. It seems like the more robust option. A little extra weight won't hurt my situation. More information on these packs and chargers would be helpful.
 
Hi,



Ok, so If you do not own a LIPO RC charger the solution to buy Lipos without BMS is not for you unless you buy a RC charger with at least 2 outputs:



http://www.banggood.com/Ultra-Power-UP100AC-DUO-100W-LiPoLiFeNiMH-Battery-Balance-Charger-Discharger-p-1042945.html?p=A720061271257201502N



And this is a cheap one with integrated Power switch unit. Yes, LIPOS are cheap but chargers aren’t. With a good separate power unit and 4 outputs it’s more than double the price.



+



LIPOS: 2x5s, you can build a 8Ah pack or a 16Ah pack with these batteries:



https://hobbyking.com/fr_fr/zippy-flightmax-8000mah-5s1p-30c.html



And off you go because normally your controller has a current limit so it won’t blow up.



With this solution you will have good torque and the speed will be the stock one maybe a bit more.





OR





You can go Li-ion but do not buy a cheap chinese Ebike pack like I did, it works but it has so much voltage sag that you don’t get much range and it hasn’t got a BMS.



Or you could buy a 48V one but your controller may detect overvoltage and then you will have to modify the relay inside (not too complicated).



If you can source good 18650 cells (not my case) you can build a 36V or 48V Pack yourself if you are patient. If you don’t own a spot welder (like most people :) ) you will have to buy cheap Battery holders like these ones (do not solder directly on the battery pads with a classic solder iron):



http://www.banggood.com/10Pcs-DIY-4-Slot-Parallel-18650-Battery-Holder-With-2-Leads-p-964983.html?p=A720061271257201502N



To this you add a BMS and buy a Liion Charger



http://www.banggood.com/36V-37V-42V-45V-5A-Battery-Charger-For-10s-10x-3_6V3_7V-Lithium-Li-ion-Battery-p-1115729.html?p=A720061271257201502N





If you can’t or don’t want to make your own pack (like me) you can buy a good liion pack with integrated BMS already built but the cost is high.



https://lunacycle.com/batteries/packs/36v/36v-panasonic-ncrb-13-5ah-bottle-ebike-battery/





But before going further my question would be: Is stock speed enough for you? For me it is ok as long as I have torque and range (don’t wanna charge each and every day for my small trips)



If you want more speed >> More Volts >> may need to change the controller >>> May need to change motor
 
I almost bought one of these, After some research I found the rear hub is geared so it can climb gradients without pulling mad amp's but its not ideal for pushing to higher speeds so I went with the 1600w brushless inrunner with similar size wheels.
Thinking about it now it would make a very efficient ride around 48v and 30 amps vs 36v 20amp stock plus run a sinesolidal controller with regen I bet it would get some decent range easy 30miles on a 13s 20ah pack and it would break the 30mph mark and feel powerful being a geared hub.
 
Do you have a controller or battery recommendation? Should I go with lifepo4?

I'm debating just spending the $100 and getting a new set of lead acid stock batteries instead of spending $500 on making it a little faster.
 
Why $500.
Get lipo multistar 10ah they are extremely cheap at hobbyking, use a turngy rc charger from same site, and buy yourself a used server PSU off ebay dirt cheap to power the charger, use a voltmeter/watthour display on the scooter to determine state of charge and your away charge in much less than 8hours and last a lot longer too, $200 tops
Only hop it up if you want its not necessary the lipos are the best way to get you learning how to treat it all then make it better on the second build.
A lot of people will steer you away from lipo but those people got cash on the hip, lipo is miles better than lead acid and for discharge it rules lifepo4 will be expensive for a decent pack.

Myself I would go to 48v with 12s because the packs come in 4s the cheapest so 6 packs is 12s2p and 48v'ish and 20ah, theres a sunwin 15fet controller 48v 1500w or 1000w with correct low voltage control but no regen that will smoke the arse of the stock one for $40 or so on eBay
So it makes sense to me to push it a little harder the price will be a few dollars extra.
 
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