E-max 110s lifepo4 upgrade

[flexy]

[Edit:]

2/6/2014 For anyone looking to do this I would advise staying with the 48V setup and getting the controller reprogrammed, If you really want extra speed go for a 3.5 KW/h lithium pack to lighten the bike and over volt to 84V or more with a new controller (Adaptto Max-E, Sabvoton, Kelly, Sevcon) The Greentime ones are too unrefined and un programmable at present. Lyen 24Fet with throttle tamer would be the cheapest.
I would also make a standard 12V wiring loom to make the bikes lights and electrics more simple and reliable.

Apparently the rear shock can be replaced with Yamaha Neos one made by RMS for a smoother ride( I fitted one and it is very soft, ok for single rider).
The front brake calipers are same as Kymco 50 and 125cc Scooters, I swapped out my front caliper for one.

Thank you to Hynek from http://www.scootland.cz/skutr-eon-e-max-50/ for the help with spares (Europe).

[End of edit]


I recently got an E-max 110s 2008 model.

This comes with the stock 48V SLA battery and 4000W motor.

I would like to upgrade it to a 72V Lifepo4 pack.

I am getting an 18 fet controller from Lyen
I'm planning to build a pack from Headway 40152S cells, in 24s 5p configuration to give me a 60Ah pack.

The main problem I have is the existing 48V motor controller and the control box for the other scooter electrics are all in proprietary sealed circuits.

view under seat.

view under handlebars.

So my main concern is fitting the new controller without affecting the existing functions.

All the visible capacitors on the existing controller and DC/DC convertor are 63V so that rules out using them with higher voltage.

Should I leave the existing controller powered from a 72-48V dc-dc convertor and keep the electrics running off that, or completely remove it and attempt to rewire as a basic scooter wiring loom?

I have no schematics for this bike, if anyone has one it would be much appreciated.

 

[jonescg]

What's wrong with the Sevcon Gen 4 that's already in there? Can't take more than 48 volts?

 

[flexy]

What's wrong with the Sevcon Gen 4 that's already in there? Can't take more than 48 volts?

I have no idea, if you think it could that would be great, I went with the Lyen 18fet because I am familiar with it, I want a bike thats reliable and easy to fix.

Without schematics, I don't want to mess with the existing electrics.

 

[jonescg]

http://www.sevcon.com/media/2104/gen4_data_sheet.pdf

According to this, the maximum operating voltage is 69.6 V, so I wouldn't go exceeding 16 cells in series. If your charger puts out a maximum of 65 V you can get away with 18 cells, but it's riskier. Still better than 48 volts worth of lead, for sure.

 

[ctirad]

What's wrong with the Sevcon Gen 4 that's already in there? Can't take more than 48 volts?

I'm pretty sure these old models of e-max have no sevcon controller. The current revision manufactured under Vmoto has, though, and can be easily reprogrammed for top speed of 65-70km/h at original 48V. But these original e-maxes are different story.

 

[ctirad]

Should I leave the existing controller powered from a 72-48V dc-dc convertor and keep the electrics running off that, or completely remove it and attempt to rewire as a basic scooter wiring loom? I have no schematics for this bike, if anyone has one it would be much appreciated.

I have some pinouts and schematics of interconnects wiring, but I'm not sure I'm permited to spread. There is not much interesting things, anyway. The original controller is a complete black box.

 

[flexy]

I'm pretty sure these old models of e-max have no sevcon controller. The current revision manufactured under Vmoto has, though, and can be easily reprogrammed for top speed of 65-70km/h at original 48V. But these original e-maxes are different story.

It doesn't look like the Sevcon gen 4 models. Here is the label.

 

[jonescg]

Ah my apologies. I was working on one the other day but it must have been the newer one. Yeah, stick a big-arse Lyen in there and overvolt the bastard to 84 V

 

[yokneamcity]

I also have a E-max scooter. I ordered a battery for a OSN Power company. 48 volt/60 AH.In future I plane to raise the voltage and to change the battery to 72V/40AH
I also want to change the original controller on Infineon.
The original controller consists of two parts, the power unit, and the logical unit. If you disconnect the power unit of the logic, the logical unitis not working. But she manages light and digital display.
But I think it's a small problem to alter the wiring as it is implemented on gasoline scooters. Set the relay for turn indicators. The original digital display is replaced by Сycle analist.

 

[flexy]

Hi,
Has that lithium pack worked OK? what range do you get from it.

I'm glad you're thinking of doing the same. I found you can bypass the main controller by feeding 12V into line 8 of the interconnect but you still need to feed 48V to the logical unit to keep the lights working.

It would be more simple if we could bypass it altogether but I haven't worked it out yet.

You have a rear luggage rack on yours, do you know where you can get those? I would really like to get a top box on mine.

 

[yokneamcity]

The battery I have not yet received. I paid for my order on February 23 and received a response from the OSN Power that the battery was ready until last week.
While lead-acid batteries on the scooter and the range of 15 kilometers.

Can you show on picture or explain more where this line eight of the interconnect?
To feed 48 volts to the logic unit, it is possible with the help of step-down DC / DC converter.

When I bought the scooter, it was already installed rear luggage rack.
But I still have one of these scooters for parts and it also with a rear luggage rack, I can send it to you (I live in Israel).

 

[flexy]

It's the wire numbered 8 on the plug circled in red below, if you put 12V into that (from 12V line on infineon controller) you can unplug it from the Emax controller and the lights should still function.

I'm waiting for a 48V meanwell power supply to act as a 72V-48V DC|DC convertor to keep the logic unit powered.

I would be interested in that rack, pm sent.

 

[yokneamcity]

Thank you flexy!
This is very valuable information for me.
This can greatly ease the scooter upgrade.

 

[yokneamcity]

By the way the quality of shock absorbers are not very high.
I've already changed the seals on the front fork. And changed the rear shock. Now I need to replace the silent blocks.
Where can I get parts?
I contacted the office in Germany. Shipping to Israel from 100 euros.

 

[flexy]

I'm not sure what you mean by 'silent blocks' bushes maybe?

You might want to try a different country distributor, it might be cheaper.

I hope light weight lithium pack will be easier on the shocks, but they might need adjusting, is there a way to make the suspension forks softer?

If we could get rid of the logic board altogether it would be much better, then just use a 72-12V dc\dc to power the lights etc.

 

[yokneamcity]

Silent block= bushes
About distributor,I turned to the Italians, they redirected me to the Spaniards.
As far as I understand the adjustment of the suspension is only on the rear shock. The front shock absorber has no control.
Why logic unit need 48V and 12V together?

 

[flexy]

Could you find correct size bushes from another scooter manufacturer?

I could only get the logic controller to work that way,
It needs the 48V for it's main power and a 12 v signal on line 8 to fool it into working without the speed control unit
I can't find another way to power it.

 

[yokneamcity]

So DC/DC from 48V to 12 V located in power unit?

 

[flexy]

No 48V -12V dc\dc is in the logic unit, I can't find a way to get it to run from 12V because it is sealed.

 

[yokneamcity]

Could you find correct size bushes from another scooter manufacturer?

I could only get the logic controller to work that way,
It needs the 48V for it's main power and a 12 v signal on line 8 to fool it into working without the speed control unit
I can't find another way to power it.

So 12 V signal on line 8 it kind of feedback to logic unit from power unit?

 

[mizuh]

By the way the quality of shock absorbers are not very high.
I've already changed the seals on the front fork. And changed the rear shock. Now I need to replace the silent blocks.
Where can I get parts?
I contacted the office in Germany. Shipping to Israel from 100 euros.

Which silent blocks you need to change? EM-40103 and EM-40104 silent bloks of rear shock ? It cost together 13 EUR. Shipping 20 EUR. If you want I´ll try to order it and ship it to you. :wink:

 

[mizuh]

Why logic unit need 48V and 12V together?

I quess that in logic unit is integrated 48DC/12DC converter and in power unit is inegrated contactor / relay which enable power unit on when you turn on by key. So when you turn by key it enables to go 48V to converter, 12V goes from converter to contactor / relay in power unit, which power on power and logic unit. I´m not so good in reading wiring diagram so I guess that it could work this way.

 

[flexy]

I've had no luck trying to use a meanwell as a 72v - 48v DC/DC convertor. does anyone know where I could get one?

 

[yokneamcity]

I have received and installed the LiFePo4 battery.
Battery from the manufacturer OSN_Power. From the A123 cells. 48V-60A/H.Weight 26 kg
The battery came charged and I rode 70 km.
After that, the battery voltage drops to 50V (3.125 volts per cell) and I returned home.
Evident in the appreciable acceleration dynamics. The maximum speed of 48 km / h instead of 45 km / h.

When I installed the battery, there were problems. Manufacturer mixed width and height. The battery was narrow and high. And the plastic сover the battery was not closed.
Then I decided to put the battery on the side.
On one side was a sticker BMS. I opened the top cover of the battery and this was really BMS.
I put the battery on the side so that the BMS was at the top.
And then the plastic is closed.

 

[flexy]

Thanks for posting all the pics, I'm glad you got it to fit.

Did you get any pictures of the inside of the pack so we could see how the terminals on the cells are connected?

I want to build a pack from the A123 20Ah pouch cells.

I calculated I could fit 124 of these cells without modifying the battery box, which would give the following possibilities.

72V 24s 5p 100Ah 120cells
60V 20s 6p 120Ah 120cells
48V 16s 7p 140Ah 112cells

I need to test with my 72v headway pack first to see how the motor performs at that voltage.

How does the scooter feel with the lighter batteries?