Masini Extremo build scooter with >30kw

[dominik h]

My Masini Extremo (Erider Thunder) build stages during the last three years.
Bought it without controller, battery and BMS.

Battery
77V 100Ah 21S5P Li-NMC manufacturer Cenat
power pouch cell continous discharge 8C / continous charge 5C.
Battery weight 72kg including 254 M4 Screws and 120mm² copper busbars. 12mOhm @20C measured at the controller terminals, including wiring, fuse (325A) and the BMS. Voltage drop at 175A 2,1V.
I even had to lengthen the battery case and the wheelbase by 3cm to fit this battery.
The battery was for free and had only done a few cycles, so why not make efforts to fit it.

Temperature controlled 60W battery heating powered from the battery. Battery fully isolated with Armaflex and foam rubber 10-30mm.

Integrated fanless charger, 2x Meanwell ELG240-42AB wired in series. Sitting under the battery housing, IP67 rated (waterproof)
Charging power adjustable from 10W-500W with a Potentiometer, charging to max 87,5V.

External 2-phase 400V charger 2x Huawei RG4875G5 in series , 7kW charging power current max 85A, controlled with an ESP32 and via Smartphone. Fully adjustable 83-117V 0-85A 0-8kw, max efficiency 97%

External single phase charger 2xVertiv R48-2000E3 in series, charging power up to 3,4kW max 42A, max efficiency 96%

BMS 200A continious and 350A up to 600 seconds, JK-B2A-24S, active balancing current 2A, died after 13 seconds with 490A, (Controller settings now 400A)

Motor QS60V5000W with new 205°C 16mm² phase wires and 40mm magnets.
I also have the original Efun 8kw Motor with double 6mm² phase wires and 45mm magnets, but inside only 2/3 copper fill compared to the QS60V5000W
(Now QS273 60H 10000W 72V with 25mm² phase wires)

Started with an SVMC72260 Controller but killed it with feald weakening.
Then until May 2023 Sabvoton SVMC72150 with 175A Peak and 165A continous. Puts out up to 14kw.
Current unlock software does not work with my controller.
Top Speed 103km/h GPS verified without flux-weakening , with 50A Flux-Weakening enabled an 77V I reached 105km/h top speed (all with the QS60V5000W Motor From my previous 73km/h 60V scooter).

Top Speed 96km/h GPS verified with 50A Flux-Weakening enabled (with the original Masini 72V 8kW Motor)

From April 2023 to January 2024 Fardriver ND72680 with up to 350Adc and 680pA , measured 490A RMS phase current with a calibrated current clamp.
(Now with Fardriver ND721800 with up to 400bA and 1400pA.)

Top Speed reduced to 115kph, because the motor (QS60V5000W) got to hot.
With the 721800 and the 10kW WS273 125km/h.
Acceleration 0-80kph depending on current settings, with 300Adc and 630pA 7,6s
(now with th 721800 and the 10kW QS motor 0-100kph 6,5seconds)

Weight, 183kg plus driver 95kg (now 193kg)

A few impressionen during the last three years of modifications.

First battery fitting test


Damaged SVMC 72260 and ANT BMS. They died with a big bang, because I played with field weakening on the main stand.

Changed all the fets on a hot plate , then it worked again for a few days, but after that it didn't recognice the halls anymore. Same happend to a SVMC72150 2 months later.



First battery load test with 7kw with an electronic load from 4,17V/celll to 2.8V/cell

After the SVMC72150 died




Took the battery out to change the link between the two 10S5P halfs and the 21th cell group. Now 6x6mm² but still to weak




After the installation of the Fardriver ND72680 and the test of the temperature controlled fan, i had to install new phase wires to the QS60V5000W, because I melted and shorted them during my uphill tests. i upgraded from 13,3mm² to 16mm² 205C wires and added a temperature sensor.
The motor with less copper is the Masini 72V 8kW Motor.



Added a 150A charge plug.



The 7kw charger 2xHuawei R4875G5 connected in series controlled with an ESP32.

Terminal program on the phone to set values.

 

[dominik h]

New 10kW 72V 60H QS motor.
Had to widen the swingarm 35mm for it.


Old and new tourque clamp, they are nececary after the 72680 was installed, because you could hear the axle turning between acceleration and regeneration.

The new motor in place


Acceleration runs with 10Hz GPS 340bA and 630pA at 80V = 27kw.

Battery was not fully charged and cold, because the heating controller died. Will also change to BMS with integrated control for the heating.

0-80km/h

0-100km/h

The start ist still slow, in the first two seconds you can feel the motor tourque rising.

The next upgrade >30kw.
Fardriver/DKYS labeled 721800
For this I have to rearange the complete area around the controller as it is huge compared to the 72680

Added a small heat sink to it, because it had none.

 

[pwd]

Nice "sleeper" scooter; I like builds like that. Were those acceleration runs at full throttle?

 

[dominik h]

Yes full throttle.
But I think I have not yet found the perfect motor and PID settings.
Sometimes you can hear and feel the controller restricting the current.

Controller data from older runs with less current.

 

[SlowCo]

Nice build!
As you are in Germany, what moped/motorcycle-class is it? Is it a L3e-A1 light two wheeler?

 

[dominik h]

I think it is L3E-A1, but I don´t care as I have also the licence for L3E-A3.
For the TüV approval every two year I reduce power to 10kw.

 

[SlowCo]

I think it is L3E-A1, but I don´t care as I have also the licence for L3E-A3.
For the TüV approval every two year I reduce power to 10kw.

Do they actually measure the power at TÜV-approval time? And is that continuous or max kW?

 

[dominik h]

They do not measure, but they always drive a few meters or sometimes up to a few minutes.

 

[dominik h]

Just killed my JK 200A BMS during a stationary load test with the electronic load.

It survived 400A for 2 times 30 seconds
It survived 450A for 2 times 20 seconds
It survived 490A for 2 times 10 seconds
It died while drawing 490A after 13 seconds.
I let the BMS cool down betweend the tests.
With 450A the temperature in the app rises fast to 55C.

I tested this with an electronic load and an 8S lifepo 20Ah A123 pouch pack.

So I will limit my controller to 400-450A.
Now it is time to install the new version of the BMS with integrated heating controller.

 

[Chalo]

Don't discharge more than 200A through the BMS. Use the BMS output to switch on a contactor that is rated for more than 450A, and wire the battery leads directly to the load, through the contactor. Then your BMS can be small and inexpensive. And the components can run within their ratings.

 

[dominik h]

Then I have to design a precharge circuit, otherwise the contactor will soon die.

I also have a 24S passiv contactor BMS from JK-Energy with nice datalogging functions, but it is to big and I have no space left for two 500A contactors.

This test was done to find the limits from the JK 200A active BMS and I succesfully found them,. Now I have to find the weak point in the BMS.
I knew it could die and I often test until something dies.

 

[dominik h]

The BMS looks ok, no burnt Fets or other burnt components.
The Bluetooth also died.

 

[amberwolf]

Or...use whatever kind of BMS you want, but run all current directly thru just the main wires--then have the BMS control line, opto-isolated if necessary, command the controller to stop running the motor, and have an alarm or light for you / the rider/user to know why it is doing that.

The "command" can be as simple as cutting the power to the throttle unit, so the controller gets no throttle signal, or if the controller has an enable or disable line (like how ebrakes work on non-regen generic ebike controllers), that can be used.


Then you eliminate at least two possible problems: the BMS can't blow up in a way that either leaves you stranded, or that leaves it permanetnly stuck on so it can't protect anything (common FET failure mode), and it can't disconnec the battery during a regen event that could cause a voltage spike inside the controller that can blow that up.

 

[Dui ni shuo de dui]

Don't discharge more than 200A through the BMS. Use the BMS output to switch on a contactor that is rated for more than 450A, and wire the battery leads directly to the load, through the contactor. Then your BMS can be small and inexpensive. And the components can run within their ratings.

But then it cannot monitor current anymore, because you bypassed the shunts by doing that. That sucks because it's one of the most useful features of these BMS.
Get an ANT BMS, the 300A version can tolerate 600A for a while. I think even a 450A version exists now, I've seen it on Taobao a few months ago

Then you eliminate at least two possible problems: the BMS can't blow up in a way that either leaves you stranded, or that leaves it permanetnly stuck on so it can't protect anything (common FET failure mode),

I've seen that happen to contactors as well, even the large automotive ones (BYD). They don't make much difference aside from being big, bulky and heavy. Personally I've never used any and can't really recommend using one.

 

[dominik h]

I will stay for this year with the JK 200A activ balancer BMS. 400A during acceleration will be enough for this scooter. The whole thing is heavy but it does not feel stiff and precise on the road.

This scooter is the test for my next build , either I build a supermoto or TZR125/SZR660 with either a hub or mid motor. The battery will be made of two 12S2P VW MEB modules.

 

[Chalo]

Get an ANT BMS, the 300A version can tolerate 600A for a while.

Yeah, ratings for components that are determined by manufacturer testing probably don't mean anything.

 

[dominik h]

They all write rated current and peak current.
Rated is in my opinion 1 hour continious or even longer.
Problem with peak is, no one knows how long it will survive the peak current. Is this 10seconds or 1second or 10ms?

That is why I tested mine to death.

I found a 380A (950A peak) 24S ANT BMS. But I do not like the 100mA passive balancee..
Probably I just wait for a JK BMS with more Mosfets.

 

[Dui ni shuo de dui]

Yeah, ratings for components that are determined by manufacturer testing probably don't mean anything.

I've tested many myself. I'm using 3 of these in my motorcycles for something like 6 or 7 years + countless other units I've installed and or/helped installed/recommended to friends and people on forums/social medias. They do handle the power reliably. Lots of people use them, maybe you should try one someday.

Also, the Mosfets datasheet is a public document anyone can check. The ones they use aren't bad at all.

Problem with peak is, no one knows how long it will survive the peak current. Is this 10seconds or 1second or 10ms?

You can set the time delay you want in the app. Usually the chinese manufacturers talk about 10 seconds peaks, but indeed that remains an open question whether its the case here. Can't recall what was the default time delay in the app, maybe 2s?
I never had a machine that was capable of pulling that kind of current for more than 2-3 seconds, once it reaches a certain speed the current usually starts dropping.

found a 380A (950A peak) 24S ANT BMS. But I do not like the 100mA passive balancee..

Weird, they usually have 200mA balancing. 100mA is a bit weak indeed, but still better than the measly 50mA of the Daly BMS.
With your 100Ah battery balancing will take a while. But hopefully you have a good battery that don't really need much balancing?
A separate balancing board can also be an option, although it adds a bit of complexity.

 

[dominik h]

Today I had a few hours without the family.
Installed the ND721800, the new DC/DC, the new BMS with integrated heating control and relocated the fan and the temperature switch for it.
With the big controller I have no need for long batterycables anymore, even the short wires from the JK-BMS are long enough.

 

[dominik h]

Today I finished the Installation.
Biggest problem is software, as usual.
The ND721800 came with the old BLE modul and can connect to the old 1.5.5 software version and to the new 2.2.8 Version. But I can't change all the nececary parameters. With the new BLE modul from my 72680 it gets recognized but it can not connect the controller with the app.

I can not set the KTY Temperature sensor which is installed in the motor and I can not change the ratios in speed.
But now with 1000pA the starting tourqe is ok.
Does anyone have a new firmware for the 721800 probably this can fix my issues.

 

[dominik h]

Still can't save parameters but everything I enter stays until I turn it off.
I made a test ride. From start it now pulls like a real motorcycle, that is what I wanted it to be.
1200pA and 400bA
0-80 km/h

0-100km/h


Still looking for a newer firmware for the 721800.
Does anyone have the pc-software?
I'm not able to download it from siaecosys or Fardriver at the moment. I have also a PC-adapter for the Fardriver and want to try if I can change and save values with the PC.

 

[dominik h]

With the actuall 2.4.9 Android App the ratios in speed could be set again to usable values.
But now the brake lever motor cut off does not work anymore. All the Inputs are now " not connected ".

New test ride, with wheel spin shortly after the start. 0-100km/h.
You can see the controller restricting phase current at 30km/h because I have limited the battery current to 400A.

 

[dominik h]

Another Support day with the technican from dkys Wuxi Dingkou.
We are making circles and circles not finding a solution.

I have spent a lot of money and time with a "worthless" product because the manufacturer says "after sales support has to be done through the reseller" and the reseller can't help, or does not know how to help in my case.
The reseller does not know which is the right new Bluetooth thing for my controller (I have a new BLE from my 72680 which connects to the software but not to the controller) nor which software or Android app fits to my controller or which firmware makes my controller work with the actual software or newest Android App.

I can drive but motor cutoff with brake or sidestand does not work and can not be changed, because all the input pins are not connected in the app and can not be changed.

With this issue it will get no permission to drive when the next TüV approval has to be done.

 

[Dui ni shuo de dui]

Another Support day with the technican from dkys Wuxi Dingkou.
We are making circles and circles not finding a solution.

I have spent a lot of mmoneyand time with a "worthless" product because the manufacturer says "after sales support has to be done through the reseller" and the reseller can't help, or does not know how to help in my case.
The reseller does not know which is the right new Bluetooth thing for my controller (I have a new BLE from my 72680 which connects to the software but not to the controller) nor which software or Android app fits to my controller or which firmware makes my controller work with the actual software or newest Android App.

I can drive but motor cutoff with brake or sidestand does not work and can not be changed, because all the input pins are not connected in the app and can not be changed.

With this issue it will get no permission to drive when the next TüV approval has to be done.

Maybe you can try to get the cable so you can connect to the computer instead of the phone?
Hopefully that should solve the bluetooth issue.

 

[dominik h]

I have the cable and can see live values from the controller, but can not save any parameters.