EVO battery seems broken, and I've been told batteries can't be repaired!! (?)

viper

New Member
I own a EVO 27.5 from 2015, and after three years and 9000Km, the bike is having a random very annoying behavior: It shuts down completely (without any error) while being pedaling, or being stopped. There is no pattern: can happen at fully charge, almost empty, on effort, idling, under cold weather or not, in bumpy terrain or totally steady...
Once it happens, the bike sometimes can be restarted, but sometimes you need to wait several minutes to be able to restart it.

I have connected a digital multimeter in the charge port (in parallel to battery output) to check what happens, and have verified the problem is the voltage drops suddenly to around 5volts, and obviously, the bike can't be started. After some time (can be seconds, can be minutes), the voltage starts going up, and in few seconds it shows back to be at nominal voltage (36 to 40 V depending on the level of charge at that moment), only at that time the bike can be restarted.

It is not a false contact issue (otherwise the voltage would go to zero, not 5-6V). My interpretation is the BMS is finding some issue and disconnects the battery.

The bike is out of warranty, so BH won't take care of it at their cost.

I have asked BH dealer and they told me this is clearly a battery fault, they won't repair and I need to purchase a new one, costing 850Eur (970USD).

I have taken it to a couple of local business who rebuild ebike batteries, and they don't want to take care of it because they found BH batteries to be very special. They say replacing cells require re-setting the BMS and there are no known procedures/tools to do so, and even worst in the case of a bad BMS, since there is no way to purchase a spare BMS.

I bought the bike at outlet price for 1450Eur, so being an old, rather outdated bike, I don't think is a wise thing to spend 60% of original cost to bring it back to life, although the truth is the rest of bike works flawlessly.

Anyone has experience on repairing Easy Motion battery packs??

Thanks in advance!
 

MarkF

Active Member
It doesn't matter what you paid for the bike. The battery cost what it cost. A new pack today will certainly have better cells than your 2015 pack. So if your bike is still in good shape, you will save money buying a new battery and not a new bike. I would make sure you can't find someone to replace your old cells before I bought a new pack though.
 

Ebiker01

Active Member
I own a EVO 27.5 from 2015, and after three years and 9000Km, the bike is having a random very annoying behavior: It shuts down completely (without any error) while being pedaling, or being stopped. There is no pattern: can happen at fully charge, almost empty, on effort, idling, under cold weather or not, in bumpy terrain or totally steady...
Once it happens, the bike sometimes can be restarted, but sometimes you need to wait several minutes to be able to restart it.

I have connected a digital multimeter in the charge port (in parallel to battery output) to check what happens, and have verified the problem is the voltage drops suddenly to around 5volts, and obviously, the bike can't be started. After some time (can be seconds, can be minutes), the voltage starts going up, and in few seconds it shows back to be at nominal voltage (36 to 40 V depending on the level of charge at that moment), only at that time the bike can be restarted.

It is not a false contact issue (otherwise the voltage would go to zero, not 5-6V). My interpretation is the BMS is finding some issue and disconnects the battery.

The bike is out of warranty, so BH won't take care of it at their cost.

I have asked BH dealer and they told me this is clearly a battery fault, they won't repair and I need to purchase a new one, costing 850Eur (970USD).

I have taken it to a couple of local business who rebuild ebike batteries, and they don't want to take care of it because they found BH batteries to be very special. They say replacing cells require re-setting the BMS and there are no known procedures/tools to do so, and even worst in the case of a bad BMS, since there is no way to purchase a spare BMS.

I bought the bike at outlet price for 1450Eur, so being an old, rather outdated bike, I don't think is a wise thing to spend 60% of original cost to bring it back to life, although the truth is the rest of bike works flawlessly.

Anyone has experience on repairing Easy Motion battery packs??

Thanks in advance!
Ask the people who rebuild the batteries to only reseat the BMS (unplug it and plug it back). And or check for any loose wires from the cells or around the Bms/ charging port. You can purchase An used battery (100-150$ on eBay/craigslist) and use it’s BMS for parts.
 

Thomas Jaszewski

Well-Known Member
Ask the people who rebuild the batteries to only reseat the BMS (unplug it and plug it back). And or check for any loose wires from the cells or around the Bms/ charging port. You can purchase An used battery (100-150$ on eBay/craigslist) and use it’s BMS for parts.
A BMS is a $12 item. But good advise on looking for an intermittent short and the wiring. Perhaps a bit more research on the brand and its battery build.
 

viper

New Member
Sorry, it took me some time to answer... but I had done some investigation. Comments in line.
There’s quite a bit to check by googling. See comments through YouTube.
You are right. I already had viewed the video, but the comments have some juicy info.

Ask the people who rebuild the batteries to only reseat the BMS (unplug it and plug it back). And or check for any loose wires from the cells or around the Bms/ charging port. You can purchase An used battery (100-150$ on eBay/craigslist) and use it’s BMS for parts.
Unfortunately, according to a comment in the youtube video, at least one person had issues of battery not charging after disconnecting the BMS.
Funny enough, I'm Spanish and you know BH is Spain based. Almost anyone here had at least a BH at some point in their life, but the warranty here covers only two years, and there is no second hand market for spares on these Easy Motion bikes as to purchase a used battery.

On the other hand, I verified whether the bike works just connecting the two power connections (+ and -) by isolating the rest of pins. The result is it doesn't work. The bike powers on, but the battery indicador blinks, the assistance indicator gets set to "No assist", and the controller does not allow to select any assistance level. Walk mode works, but only at 6Km/h.

There are some other suggestion in another thread in this same forum about using another battery. I'll post there and probably would be better to continue there.
Thanks for your suggestions.
 

Thomas Jaszewski

Well-Known Member
Sorry, it took me some time to answer... but I had done some investigation. Comments in line.

You are right. I already had viewed the video, but the comments have some juicy info.


Unfortunately, according to a comment in the youtube video, at least one person had issues of battery not charging after disconnecting the BMS.
Funny enough, I'm Spanish and you know BH is Spain based. Almost anyone here had at least a BH at some point in their life, but the warranty here covers only two years, and there is no second hand market for spares on these Easy Motion bikes as to purchase a used battery.

On the other hand, I verified whether the bike works just connecting the two power connections (+ and -) by isolating the rest of pins. The result is it doesn't work. The bike powers on, but the battery indicador blinks, the assistance indicator gets set to "No assist", and the controller does not allow to select any assistance level. Walk mode works, but only at 6Km/h.

There are some other suggestion in another thread in this same forum about using another battery. I'll post there and probably would be better to continue there.
Thanks for your suggestions.
Without some additional information it’s hard to trouble shoot. Some multimeter reading are a first step.
 

Thomas Jaszewski

Well-Known Member
The biggest problem with repairs is shipping. If I compel you to ship me a battery and there’s an issue in shipping, I bear the responsibility. Legally shipping problem batteries is a slippery slope... I’d look to a custom builder to rebuild or build a new. Likely for far less $$.