My Finished 72V (88.8V) 50A Highly Modified Electric Scooter

[eganwp]

Hi guys,

So bear with me as I'm new to the whole e-bike show, but I'm not new to electronics or LiPo/A123/LiFe, etc. work as I fly giant scale RC planes and much of which I build electric setups.

So here's my quesiton I'm needing your expertise on. Looking to mod my newly purchased 2011 Gimelli E-Sport scooter/moped w/ pedals for more speed and torque. The guy I purchased it from says it does 70kph ungoverend with the stock SLA 48V 20Ah setup, though I find that hard to believe but haven't ridden it yet as the stock 48V SLA packs are toast. The controller is a MTL Brainpower Motor Controller (48V, 120 degree angle, 33A current limit, 42V +-0.5 low volt, brake 12V). Haven't taken a pic of the motor, but I'm guessing its a 500W motor, not sure on kv though.

So I'd like to hit this bike up with my own LiPo setup as I can do it for a lot cheaper than A123. I'm thinking 66.6V (75.6V full charge), 10Ah, using 6x 6s1p 5000mah LiPo's. Or I could even go down to 6x 5s packs, or 4x 8s packs even. Just not sure what is the best way to go as the cell count is optional, but what controller/setup is common that would suit eachother nicely?


Assuming I need a new controller (or maybe I don't?), what controller or brand do you recommend? I know I should find something with reasonable cutoff voltage at 3.5-3.6V/cell but I may just use a meter. What brands or sites do you guys recommend here? Or maybe you'd recommend a new motor/controller/pack combo that would suit my needs? Not sure if 20A or 50A+ is what would make me happy, or what those stock motor windings can handle. Doesn't need to be insanity, but if I could do 60kph with ease and moderate torque, I'd be set. 30km minimum range.


Thanks for any help I can get guys!

 

[jonescg]

Where abouts do you live? I have been assembling batteries using the individual 5 Ah cells from Hobbyking. It seems to work quite well, and the pack ends up being far better quality than what HK could come up with. Check out the link in my signature and see if it might work with what you have in mind.
Cheers,
Chris

 

[melodious]

Before you dive into the battery, figure out what the motor is. Brushed or brushless? If it turns out to be a brushed motor, you're probably limited to how much watts you can dump into it before things get toasty.

 

[Ykick]

I tend to stick with 15S Lipoly - 60-62V for unmodified 48V SLA setups. My reasons for this - 63V caps, less need for pre-charge connectors, better bulk charger availability and my Turnigy power meter still works up to that voltage. I'm lazy and don't like to mod things for mod sake plus I prefer reliability over top speed.

 

[eganwp]

Before you dive into the battery, figure out what the motor is. Brushed or brushless? If it turns out to be a brushed motor, you're probably limited to how much watts you can dump into it before things get toasty.

I've emailed 3 or 4 vendors to see if they can get me any data on the motor. BTW this is a HUB motor on my e-scooter. So I assume they're all brushless aren't they? I have no idea on the kv, but I'll see if anyone gets back to me.

Hope this helps. Pic below.

 

[amberwolf]

BTW this is a HUB motor on my e-scooter. So I assume they're all brushless aren't they?

No.

Two wires in, probably brushed. Eight (three thick five thin) wires in, probably brushless. Other numbers also possible if has thermal sensors, spare halls, etc.

 

[eganwp]

Alright just got finished pulling the hub on this almost new e-scooter. Hub is labelled MTL48V100100060. It's a brushless motor 3main wires 5 small ones for hall sensors.

Looks to be 20awg wire on the 3 mains running the brushless motor after comparing wire sizes and measuring with my micrometer.

I've been measuring and I may be able to stuff 3x 16awg wires down the hub shaft but it'll be tight. 18awg would fit easily, but not sure that 20-->18awg is even worth the upgrade or hassle.

What do you guys recommend as far as power handling down these stock wires/motor? I would love to go 24s2p for 88.8V nominal, 100V peak charge to get me near that nice usable 60kph. Would 45A peak, probably 10a? normally be pushing that motor or wiring too hard? I plan to buy a Lyen 9 or 12 FET controller unless there's something else u recommend instead.

Thanks!

 

[dnmun]

did you open up the controller yet? can you read the capacitor voltage rating and read the part number on the mosfets? also what is the value of the input power resistor?

 

[eganwp]

Capacitors (4 large ones) are 63V 470uF each

The mofsets say:

Row of them along heatsync:
T430 BN912Y

Main big one:
DC062 K3GF

2nd biggest one:
358 EF746

Not sure which is the input power resistor but if its the big white one its 3W 180AJ

 

[eganwp]

Well I had a chance to test this tonight.

I took 4x Gens Ace 2500 25c 4s lipo packs and built 3 series harnesses for them with Deans. Worked perfectly for testing. So I'm currently testing 16s1p 2.5Ah for 67.2V peak at 33a for a nice modest 2200w (up from 500w stock). I took my GPS along and the e-scooter does 46-47kph flat and level consistently. I've never ridden one of these e-scooters/bikes before and i never tried it stock on 48v sla's. I got up to 55kph on a very slight decline. Acceleration is pretty good, especially with that rediculously heavy sla 48v 20ah pack out. The controller was just above cool to the touch, and the hub motor and wiring were pretty well cold. The packs were a little warm but I was drawing 33a out of each (12c)


This is a nicely easy to mod setup with all the stock parts except lipos. Did 3 full 16s packs worth of tests. I took it on one of the main roads just to test for speed and I still think I would like to up my speed to an easy 60kph for general use. I think for this I'll have to go from 67.2v up to 100v and get a new controller. That way I can go with 12x 6s 5000mah packs for 24s3p 15Ah. If I stay as is I'm going to buy 6x 8s 5800mah packs for 16s3p 17.4Ah.

What's your guys' best recommendation for 100v 45a controller? I'm liking the Lyen 12 FET but I'm brand new to all this e-bike stuff so I'd like your recommendations!

 

[eganwp]

Anyone?

Just looking for your recommendations for the easiest/best plug-n-play controller for 72V or 100V input.

Debating Lyen, Kelly and Infineon 12FET controllers but I can't decide which would be the best choice. Not sure i can program the Kelly's take-off amperage down for the 20awg motor wiring unless I drill the hub input and put in 16awg.

I dont need regnerative braking. My current controller is rated for 120* angle, but most of these controllers dont list their angle which im not sure if it matters??? Which one do u guys recommend?

 

[eganwp]

Rewired the small 20awg leads to the motor last night with 16awg copper wire. Should nicely boost efficiency and power as I could feel the 20awg fairly warm at 67V. Running the numbers it looks like I'll gain 2.5% or 1.6V at 33A/67V plus efficiency. I'll hook up my watt meter next and see what kind of amps I'm pulling before I go buy a Kelly or Lyen controller.


Guys where are the dc/dc converters generally located on these mopeds for running lights, horn, etc. Also what's their typical max voltage rating? I never hear anyone talking about them when modding so maybe there's no issues.

Thanks!

 

[eganwp]

Just figured I'd leave an update.

Went for a couple spins on my 16s test packs and watts-up meter. Pulling the controllers max 34A for 2000 watts, 50km/h.


After way too many weeks, days and hours spent i've decided on the following setup:

12x 5s 5000mah Turnigy Lipo packs for 20s3p 15Ah for a top speed of 60km/h.
Lyen 12 FET controller @ 45amps continuous
Cruise Control
3 Speed Switch
TTL programming cable, CA adapter
Cycle Analyst (most likely anyway)

I'm still debating going 12x 6s 5000 packs instead for 100.8V 15Ah, but running some numbers and graphs on ebikes, it looks like my amp draw at WOT will be a little high @ 42.5amps for 68km/h. I don't wanna fry this little 500w motor, so pushing 3780w through it at 20s lipo will already be pushing it pretty hard, but my amp draw is much lower at 33.5A for 60km/h, 1110Wh.

 

[eganwp]

Wow, it's been nearly 2 years since I updated my original thread! I had totally forgotten about it but wanted to update it just for others as well as my own reference's sake. I hope this will help someone in the future. I've been riding my highly modified high performance electric scooter for over 1.5 years now! Wow she's a blast. Can't believe how amazing a project this has been. This thing has been amazing, and I'm hoping to build an electric car sometime in the future.

Rather than retype out all the technical details of my final build, I'm just going to re-post my for sale ad I posted elsewhere as all all details I listed there, rather than taking the time to retype it all (aeilbit somewhat untechnically speaking for buyers to understand, so bear with me).


HIGHLY MODIFIED 2011 Gimelli E-Sport 72V Electric Scooter/Moped/E-Bike

I bought this electric scooter with the standard heavy & slow 48V lead acid batteries. I then invested an additional $1200 & over 100 hours of my time in order to make it into an AWESOME, high performance e-scooter to ride on hilly Pender! You cannot buy anything like this from a store anywhere, and custom built versions like this are often $4000-$10,000! Even the guys at Go Time Motorsports in Victora were blown away by this thing! BTW, you can buy parts and get support from them as they sell the Gimelli brand electric scooters there. Save yourself some serious money on paying for expensive gas, insurance, and repairs on your car and join the electric vehicle revolution!

Details:
- 2011 Gimelli E-Sport 72V Electric Scooter (Moped/E-Bike)
- Only 2177km on it! Almost new!
- Extremely reliable with modificiations. Just plug in to any 110V outlet to charge. Perfect reliable, maintenance-free daily driver.
- Costs only $0.10 to "fill-up" with electrons!
- Has over 100km of range before needing a recharge at 32km/h!!! (Stock scooters wont even do 1/3 of that range in practice.)
- Has a top speed of over 70km/h flat & level, GPS tested. (The speedometer says you're going over 100km/h as most scooter speedometers I've tested are way over-rated).
- ~2-4 hour max recharge time.
- Lithium battery will last 10+ years easily, vs a lead acid that needs to be replaced every 2-3 years and will cost $$$ each time.
- I added cruise control to the e-bike.
- I added a 3-way toggle switch for 32km/h, 50km/h and 70km/h+ depending if you want to ride for performance or range. Adjustable while driving.
- Governor can be enabled to never allow speed to go over 32km/h.
- Battery regeneration is fully enabled to allow the motor to act as a generator while coasting down hills or stopping (anytime throttle is closed), using the power to recharge the battery instead, as well as aid in braking to slow down. On Pender this is a great feature, as there are so many hills which offer a huge amount of "free" power being put back into the batteries.
- Pedal assist
- The slow, heavy, pathetic 48v lead acid batteries were torn out and replaced with custom built top of the line 72V (88.8V fully charged) Headway Headquarters LiFePO4 Lithium Cells (24 cells). These are the exact same Lithium batteries used in very high performance electric sport cars & street bikes now entering the market.
- Stock small controller replaced with a top of the line CellMan (emissions-free.com) 12 FET 4110 72V Infineon Controller. PC Programmable & I will include the PC interconnect cable to modify the controller settings (like amperage, speed, regen, acceleration, etc)
- Took out the stock 48V DC-DC controller to run all 12V accessories/lights, and replaced with a high voltage 72V DC-DC controller.
- Nearly the whole bike is re-wired with much high quality copper wire with much larger AWG to handle the increased current load of the new setup. I even re-wired & greatly upgrade the AWG on the phase wires entering the motor windings in order to handle the vastly increased power.
- Stock 500W+ motor
- I added a 2-way dual 30A breaker so main power can be disconnected during storage, and also a safety feature incase an issue were ever to occur.
- I added a custom engineered 24cell 50A 72V Battery Management System (BMS) to the Lithium Battery Pack in order to manage each cell individually to protect it from damage from overcharging or overdrawing capacity. Configured to fully balance each cell in the battery pack each and every charge for maximum capacity & cell health for longevity. It will also shut the bike down automatically if any cell falls below minimum voltage threshold.
- Comes with not one, but two 72V (88.8V) chargers! Leave one at home and the other at work or school, or even haul it with you in the rear carrier in case you want to do a really long trip.
- Comes with nearly brand new flat black HJC DOT safety approved motorcycle helmet w/ built-in retractable sunglasses & cloth bag.

- 2x BNIB chains for pedals
- 2x cans of matching touch-up paint.
- BNIB heavy duty motorcycle grade tire inner tube incase you ever have a flat
- BNIP never used wheel locking cable
- BNIP never used Tire Pump
- Stock Controller (works great) that was removed
- All stock connectors/adapters/plugs that were removed
- All instruction manuals



Here's some pics of the project for those interested. God bless you guys!

Travis - aka Eganwp

 

[eganwp]

Just a few pics of the build project.

 

[eganwp]

The for sale pics...

 

[eganwp]

Even my wife loves riding it!

 

[dnmun]

you know you are violating their rules by selling it here? next thing they will warn you that you will be banned for violating their rules they made up.

you should enter your address somewhere so people have an idea of where it is located.

 

[eganwp]

a) I'm not selling it here. I said I'm just quoting my for sale ad I have posted elsewhere because I included all the details of the project, rather than re-typing them all...
b) I'm not including my address, price or anything because this is a project overview intended to help others out, not a for sale ad.

But thanks for your concern...