Disappointing Service from BionX and it's 48V Battery

Frances Willems

New Member
Just a word of caution to anyone contemplating buying a BionX e-Bike... in my experience the battery life is very short-lived and the after-service care from BionX is not going to be there for you.:(:(

This is my experience: Two months out of the warranty period (26 months after purchase) my BionX 48V no longer worked. I took it to an e-Bike specialist who identified the problem being with a circuit board inside the battery pack. To replace the circuit board would probably cost no more than $100. However BionX policy is not to replace spare parts or components. Their solution to me was to replace the battery pack at a 20% discount. I have already spent over NZ$3,500 on kitting out my e-Bike only two years ago and do not have the money to buy another replacement battery. And why would I spend an additional NZ$1,800 (albeit discounted price), knowing that the battery life is good for only 2-3 years??? :(

For background research/information on this, please read on.

Message from my e-Bike specialist in New Zealand

I've done some more research on the BionX system - Sadly it's very depressing !
BionX use a complicated communication system between the battery, handle bar display and the motor. It's an unnecessary, and overly complicated system, that very few electric bike companies use.
Most companies don't have such a communication system, and thus you can replace their batteries with other standard batteries.
Sadly with BionX it means it's very hard to use a different type of battery. I found one person who has, but he found it difficult, complicated and the bike was erratic and lacked a lot of the functions and safety because the new battery wasn't able to communicate with the rest of the electronics
Because of safety I don't see this as a good option.

I've found one guy in USA who rebuilds the 36v and 40v battery packs, but he doesn't repair the circuit boards, so can only do this for alive batteries that are slowly getting old.
He's never done a 48v battery, it really seems that they just don't last
I've tried to find replacement battery circuit boards everywhere - sadly nothing !
BionX don't provide any parts and the only one I could find from Wanaka was faulty in the same way as yours.

The controller is built into the motor itself, thus it's hard to bypass the controller and just use the motor.

So, I'm really sorry but it feels like a brick wall.
I'm not sure what to recommend for you to do.
If you want to use your existing bike there are few options.... Perhaps ask BionX for an extended warranty ?
If they can guarantee or warranty their battery will last for 4 or 5 years it might be worth it, but if it's going to die after 2 or 3 years then it will leave you in the same unhappy position

I would definitely recommend you post on forums your experience with BionX and their terrible customer service. Their lack of technical support and Zero replacement parts for their batteries

Message from me to BionX

Thank you for your email, disappointing as it is. Yes, I do have a few questions regarding my BionX experience. Can you perhaps see it from my perspective? Why I would want to pay another $1800 ($2,000 less the 20% discount you are offering) for a new battery to replace one that lasted only two months beyond its warranty period? I’ve already spent a small fortune to get the bike I wanted and do not have that kind of money to buy another battery (20% discount or not); it's simply inconceivable for me. Besides that, your product does not inspire confidence, and neither does the service you are offering.

My ideal solution to this would be a replacement battery at a maximum cost to me of $NZ$300 (because that is all I can afford to pay, and how much I am prepared to pay for a product that I’m not totally confident in).

Message from BionX to Me, 9/07/2016, at 4:39 AM

Hello Frances,
Thank you for contacting BionX and telling us your concerns about your battery. The reason to replace the battery fully is to encourage people to NOT open up a lithium battery and change parts. All of the BionX batteries can be recycled, opening a battery can cause more issues to the system if the work is done poorly. That being said, BionX is willing to offer a replacement battery at 20% off as a part of our loyalty program. Contact a local dealer to order the battery, they will contact us regarding the discount.
Feel free to contact me with any questions you may have regarding your BionX experience.

Kind Regards,
Technical Representative | BionX International

General Inquiry from Me to BionX, Friday, July 08, 2016 7:53 AM:

I purchased a BionX 48V battery kit from Sydney Bikes (Sydney Australia) in March 2014. It was shipped over to me in Christchurch New Zealand and installed on a bike I purchased locally. Unfortunately the battery displayed issues 26 months later (two months after the warranty period). I took the battery into to a local e-bike specialist and he found that the BMS circuit board was not working. He tried to source an operating BMS circuit board from a BionX dealer in New Zealand and also from a dealer in the USA, and Australia, and the feedback he receives is always the same, i.e. that BionX refuse to supply replacement parts, there’s no source for aftermarket BionX BMS units, no real source for surplus units, dealers only carry complete batteries, BionX do not allow any battery repairs in the field (it is always a swap scenario, warranty or otherwise), BionX policy is to encourage to buy whole bikes, not supply individual parts.

With all the online research Ants has done, and communication he’s exchanged with other e-bike dealers, I feel he’s exhausted all avenues to acquire a simple, relatively inexpensive circuit board (SMC rev 6.3B BMS) to fix the problem.

I would like to express my extreme disappointment in the service that is being offered by BionX. I bought an e-Bike because I wanted a cheaper and more environmentally friendly mode of transport to commute to work. This is proving to be not the case. The bike cost me NZ$3,500 to kit out (including NZ$2,380 for the BionX Battery), and now I’m expected to pay an additional $2,000 to replace a battery that is only two months out of its warranty period. As for the environmental implications, I am truely shocked that BionX should condone replacing a battery when a more environmentally sound proposition would be to re-use the battery if at all possible and encourage replacement of simple components such as a circuit board. The current BionX solution would to me seem to contradict your mission statement of providing “alternative transportation solutions that enable environmental sustainability and a higher quality of life”. I cannot see how the stockpiling of faulty batteries is demonstrating environmental sustainability. I think BionX needs to show some accountability for how it deals with its faulty batteries.

I’m not sure who to turn to now in order to find resolution to my problem. Is there any advice or direction that you could recommend to me?

Kind regards,


Well-Known Member
You're probably SOL. If your guy can check the mosfets, diodes, capacitors and two board batteries, may he will get lucky and find the defective component and just replace it.

If it were me I'd hit them up in social media. Warn others and maybe they will help

Frances Willems

New Member
Hi JoePah, thank you for your suggestion to post to social media. I've just done that now. Great idea! I'll also pass on your response to my e-bike specialist.
NZ$2,380 (€1500) seems like an redicoulous amount of for a battery That hardly costs a €150-200 to manufacture. On american sites i can find their batteries for $825-$1,225 which is still quite expensive.

I repair batteries in sweden and if you contact me maby i can help: http://batteridoktorn.se/kontakt/

And to JoePah, there is often not possible to repair BMS since they use microcomponents:http://batteridoktorn.se/wp-content/uploads/Zundapp-10.jpg

Also the most common BMS error is waterdamage and water damaged electronic just cant be repaired.

But if repairing is your only then cleaning it with alcohol or distilled water when disconnected is the best alternative.

I dont know how the bionx system works but i guess it has more than 2 connectors from the battery?

Usually some BMS have a voltage stepdown, on Bionx probably to 24V since their system used to be 24V. But it might also be 5V since its used for PAS/GAS and sometimes light.

Let me know if you need any help.

Cameron Newland

Well-Known Member


New Member
Thank you batteridoktorn, yes, it is very expensive for a battery !

Particularly when BionX refuse to supply any parts for repair !!

I'm the Battery Specialist in New Zealand that tried to fix Frances's battery.
No, they don't have two wires going to the battery cells -> The BionX 48v battery has multiple temperature sensors embedded amongst the cells, and a wire from each cell to the BMS for individual cell monitoring and balancing. Thus 20 thin wires from pack to circuit board in addition to the plus and minus wires.
BionX use very complicated communications systems on their e-bikes -> the CAN BUS system (usually used on cars)
They also use a very unusual charging system where a 26v power supply plugs into the battery and powers a DC/DC converter to charge the 48v battery.
They don't step down the output voltage, it's output is 48v, but there are two FET's that must be enabled by the microcontroller on the BMS circuitboard. These battery FET's were blown but they were an unusual SMD footprint and without any technical support from BionX it was impossible to tell if there were any other faults on the board.
Because of these complications it wasn't an easy option to replace the BMS circuit board, I tried and tried to get BionX to replace the damaged circuit board, they simply refused :(


New Member
Thanks Cameron Newland, I have been in contact with Russel :)
Russell does rebuilds - sadly it's impossible to rebuild a battery pack without a working circuit board.
He doesn't have any 48v circuit boards !

I trawled the web, no one has them :(
One guy has seen about 20 himself, but all were damaged or fried in one way or another :(
His opinion was that they were very unreliable.
BionX simply refused to supply me (an e-bike specialist) with replacement parts.


Well-Known Member
Year ago a co worker inherited an old Mercedes 230 Sedan with the big 6 cyl eng. The car needed a new carburetor, which was very expensive.

You know what the guy did? He tossed the whole engine and dropped in a Dodge Dart slant 6 engine.. Fit fine and was reliable and cheap to fix.

You could toss the Bionx Controller, display and BMS and replace it with standard generic Chinese parts for around $300.

and make sure you send a pic to Bionx thanking them for inspiring you!


New Member
JoePah -> Yes I thought about this, but BionX use a controller embedded into the motor :(
Because of their complicated CAN BUS communication system, the motor needs the battery and the display to work.

Yes, it would be possible to replace the motor, controller, display and battery - but that is replacing EVERYTHING :(

Anita W

New Member
Oh they just suck!
Unfortunately there are many companies like this, not just Mercedes and Bionx, and it will get worse with protectionism.

Your statement is exact, the system needs all the components to work. That is the battery, the wire harness with all good connections, the console and the motor

The first step is to identify which part is defective

1 does the charger and battery still talk and work, I.E. does-it charge or show signs of life?

2 on the charge port, you should be able to see the battery voltage on some contacts. Which contact depends on the battery model. Open the charger plug to see which pins are used.

3 Something easy to try with the dead battery: Pull it off the bike, let it sit for a while.

With the row of 3 pins on the back facing up, short the top left pin to the nearest large pin. A good battery pack should beep. I demonstrated that while you were down here, and I've got a photo of the right pins to short here: https://syonyk.blogspot.com/2016/01/trek-valencia-ride-bionx-battery-pack_23.html

On the large pins the voltage will be present for 10 to 30 seconds, then the battery beeps OFF

If the battery responds, the trouble is somewhere else

If the battery does not respond, it could be that it was discharged too deep (I.E. long storage without monthly recharging)

The Bionx charger (and many other) needs the battery to supply some voltage (17V on my 24V bike) to start the charger

You may need a lab power supply and feed the bike via the charge port, see if any response

To proceed any further you need a working battery!

Anita W.

Ken S

I clocked 32,500 km on one battery in 28 months, and it was still operating at I would estimate >80% of original capacity, and have had fantastic service from Bionx and their both of the dealers I have worked with. I would and have gone back to them with an upgrade to a 2017 model