E+ powered by A123 20 Ah pack UPDATE

So I built my 36V A123 12S pack for my E+.
It weights 7.2kg and contain at least 2.5 more energy that 7- 8kg NMH hub battery,
And tested on my E+ and
it was fantastic ride.
The weather around 20C , wind around 15-20km/h.mostly flat.
From the test it was clear how factory NMH hub battery restrains and restrict motor from developing full potential.
NMH discharge curves are rather miserable comparing with A123 discharge graphs..
As it's known E+ uses the most sophisticated motor control scheme for its BLDC motor - vector controlled technique and deserve good battery. .
I rode 25.7km and used 8.26Ah.
I pedalled just for 5-8seconds on acceleration. BTW pedalling with standing up on pedalls was pretty scary with high centre of gravity - I cannot imagine riding ebike with 8kg of battery above rear wheel every day. AS you see my frame I will be mounting battery low between pedals. That why I choose Biria frame.
Used 325Wh of energy.
NMH hub battery is quite strong during first 1-3km and start to deteriorate quite fast.
So initially E+ can reach 45-47km/h but only during first kilometers of ride.
To start with A123 charges to 43V , E+ factory NMH charges to 41V.
Because of speeds I reached I rode on the streets only.
I was riding in level 8 only /out of 9 levels/
I reached and sustaned over 50km/h every time I had streach of road in front of me,
Incredibly E+ drew only 1200W during 52-53km/h sprints which testifies how efficient Eplus is.
I remember seeing 36A at over 50km/h couple of times.
All electric reading from CA, speed from CATEYE computer, E+ shows tipically 2km/h to much according to GPS on my Elpus.
Eplus on power up goes through initialization when disply/controller does handshake with other components of bike and if everthing OK connect NMH 36V to the motor. But you can disconnect power to the motor and connect your own 36V to that motor and initalization would not detect it. System doesn't care if it is its own 36V or ouside one.All the sytem cares about is if there is any 36V connectedto the motor.
PLEASE remember that all those speeds are achived with idle 10kg NMH weight in front wheel.
Next task for me is not easy one to get rid of front hub. I am sure it can be done.
BTW as from the gossips circulating around EMS does not sell ebikes anymore but Rick still provide tech support which was great in my case.
Thank you Rick.
What brought EMS down was foolish decision to choose LiPoiymer cells for their B battery which resulted in fire in one of bike shop which forced to issue recall of their Bbattery.

I forgot to mention that I am 66kg and the temperature during test was around 20C at that time.
Almost all time flat.
Tires inflated to around 50PSI , I never inflate more than 50PSI.

Nice work Miro...

How did you wire the A123? Did you parallel the pack with the front hub battery or did you just unplug the front hub battery and plug in the A123?

From what you're saying. You simply disconnected the front hub after initialization and plugged in the A123 pack?

Ambrose

miro13car said:

Eplus on power up goes through initialization when disply/controller does handshake with other components of bike and if everthing OK connect NMH 36V to the motor. But you can disconnect power to the motor and connect your own 36V to that motor and initalization would not detect it. System doesn't care if it is its own 36V or ouside one.All the sytem cares about is if there is any 36V connectedto the motor.
...
Next task for me is not easy one to get rid of front hub. I am sure it can be done.

Click to expand...

Ambrose
You seeing it right
I simply disconnected power wire on the motor side and pluged A123 pack
To avoid spark from rail capacitors I used precharge resistor
Switching over does not have to be during initialization
You connect A123 pack and press power switch and Eplus goes through initialization with no problem
Of course hub battery put out 36V after every successful initialization
You can use this 36v for something else

That's great! Do you ever need to plug the front hub battery to the motor? I guess you still need to charge the front hub once in a while if you're not using it often.

I think I see a Cycle Analyst shunt on the frame of your Biria. What kind of readings are you getting? What is the voltage of the A123 fresh off the charger? How much sag are you experiencing under full load? etc.

Thanks,
Ambrose

Just like on TF regen is not activated unil Nmh discharged a bit
Of course Eplus BMS does not know that third party battery is on power rail
Motor controller thinks is connected to hub battery of course
So I discharge NMH a bit by riding it for about 2km and switch to A123.
A123 is not scared of high charge carrent but I don't want to pump
Amps into it when is full

Thanks Miro13car.

This is good information.

Ambrose

Hey mirocar
That battery build looks quite interesting. Can you show some details on the cell interconnects? Looks like neat work!
otherDoc

Ambrose
I didn't answer all your questions.
Typical reading on CA would be 33-34A , 1300W at 52-54km/h.
Of course I could not maintain such speeds for longer than 4-5 minutes at the time
not because of Eplus but because of road like trafic lights, other vehicles, pedestrians.
Eplus is a wonderful exercise machine , it feels so much that it wants you to pedal along with constant speed increase. I run out of high gear at about 50 km/h on this ebike.
Temperature?
Motor gets warmer than on NMH but just warmer nowhere near hot. This motor/controller is well protected by all kinds of protections: overvoltage, over Amps, overtemp., etc.
A123 sag under load? Even during hard acceleration voltage never dropped below 38V even after riding 24km.

OtherDoc,
metod of construction of my A123 is pretty simple.
+/- terminals squizzed together between two 2mm-3mm aluminium tabs with 6-32 brass screws and nuts.
I put this pack together strictly for electrical tests with E+ system. I was concentrating on how would A123 12S work with E+ system.
I would never ride this set up in my right mind. Wooden box is only to hold cells pressed together for temporary tests.
Of course no battery over rear wheel , no way, battery will godown there between frame and cranks.

Thanks Miro,

How are you charging the A123 pack and what is the voltage of the pack fresh off the charger?

Thanks,
Ambrose

I charge my A123 with 18A BMSbattery charger set up at 43.8V .
I already install yellow waterproof box to carry charger on my E+

Fresh off the charger my pack voltage reads just above 43V.

Thanks for that info.

Miro -- that is some great work. It gives the rest of the E+ owners hope that our bikes wont slowly die with the NiMh front hub. I'm glad your getting some support from Rick!

Keep up the great work -- if you come up with a feasible solution, you should start selling the "NEW and IMPROVED" E+ Aux packs we've all been waiting for for years now!

Kaysellter
Thank you for support
I wish Rick all the best, he still answers the phone and provide repairs
The worst thing I stll did not meet any technical knowledge owner to discuss how to get rid of front hub
You can imagine that with non Eplus battery you pushing slightly over 10kg of NMH in front wheel just to power BMS in purpose not to loose communication
Very primitive solution would be to instal very small 36V battery in front wheel to power electronics

Miro - yes that he does. It is unfortunate that all the prices have doubled

Miro -- go back to the TF forum and look at Bill Von's work. He has also added an aux LIPO battery to an E+--- but he does use both together with the front hub. I just checked myself..

Is your front hub done with ? Or do you just want to focus on AUX Lipo alone?

Miro - it was my understanding that with the original E+ Aux battery packs you could ride on that pack alone without the NIMH front hub-- am I wrong?

If that was the case then there should be a solution to avoiding the front hub all together no?

My front hub is on my Eplus maybe I was not clear enough and will be there for sometime
I corresponded with Bilvon but his answers were deleyed and spare
So everything died out
Powering E with nonElus battery plus NMH still on bike is rather simple electrically
My and your NMH will die away slowly just the metter of time
With my usage and many owners usage A123 20Ah. can last 10 years easily and it weights less than 8kg /!!!/

Just to make this clear
I never ask Rick any questions about any battery conversions work Eplus
Kayselters

As I said it is possible to get rid of front hub batt and ride only on non -Eplus battery but it would take some experimentation to figure it out and still there is a risk to kill BMS electronicsh

I too have an A123 battery powering an E+ 1000 watt system and it is quite a fun experience! At full throttle, my CA reads close to 1500 watts and 40 amps!

My setup is a 39volt 11.5ah battery that I purchased from Cell Man and it is wired to the rear battery Delphi plug with a CA wired inline as well. When the A123 is connected, I make sure to have the NiMH battery disconnected from the front Delphi connector since I was advised not to have both in parallel at the same time due to the different battery chemistry. The front data cable is connected at all times.

What I have noticed is that my E+ system will shut off at exactly 10 minutes to the second when I do not have the NiMH plugged in and only have the A123 plugged in. This requires me to turn it back on again. Has anyone found a way around this?

During ride with yourA123 powered Eplus NMH hub battery is idle, no power draw.
Motor draw power from A123
As we know Eplus shut down after 10 min. inactivity.
So here you have explaination

The system going to sleep every 10 minutes is definitely not due to thermal reasons as it shuts down at exactly 10 minutes every time. This is the case regardless of what level I'm in or how fast I am going. Perhaps, the system checks the NiMH battery and doesn't detect any significant change in current so it thinks it is idle.

I believe it is a shut-down timer -- just as when I leave my bike on the street just standing there. I have not yet timed it but it seems right around the 10 minute mark that the computer shuts itself down. I am guessing that without the NIMH it must just think it is idle like you siad.

ebikes rfun can you better explain how you wire this pack in? Is it possible to make a pack like this with a delphi connector that would be plug and play with the E+? I don't mind unplugging the front hub if I have too, but I am trying to figure out an AUX pack. It seems like you guys have it figured out...

Also, speaking to Bill Von, it seems like he runs his packs in parallel. So I see Ebikesrfun says that there is a danger in doing this -- so is this the consensus -- build an Aux LIPO pack, get a suitable connector on the end and then ride it while keeping the NIMH battery unplugged?

Thanks all for your advice and glad to see you guys are having success!!!!!

i'm not familiar with the E+ or tidalforce BMS that you are talking about, but why not parallel the lithium with the nimh using some low voltage high current 'fast' schottky diodes?

your lithium could start from full charge above the nimh and end up with both the lithium and the nimh at the same voltage at the end of discharge, so you could use the max capacity of each. it could be lipo or lifepo4 and the diode would have to be bigger than the voltage difference between the two packs if they both end up discharged to the same voltage. i guess it all has to be under the 57V HVC that was mentioned?

My ultimate goal is to get rid of NMH on my Eplus
NMH circuity consists of two boards: DSP board and power board
Of course I don't need NMH functions for my A123 ,it has it's own VMS
I need factory BMS active to maintain communication on RS485 going with display/controller and motor so the system will not generate error
The trick is to get DSP board cheat into thinking that is connected toNMH while in reality is connected toA123
It is not simple because among other things circuity includes 6 sense boards
Proper voltage must be fed into such board to simulate NMH voltages
Also I don't need power board so would happen if I cut it off from DSP board?
I already disconnected Nmh string twice and connected back
While powered I disconnected several sense boards and system still did not generated error
For my experiments I need another Eplus

This can be achieved by making NMH