Troubleshooting a BBS02 e bike

BrianK

Well-Known Member
Region
USA
City
NOVA
Hi folks,
Due to serious health troubles, I parked my Rambo e bike with a BBS02 system in the garage at the beginning of September. I finally pulled it out this week, dusted it off, charged the battery overnight and tried to go for a ride the next day.

The first thing I noticed when I charged the battery was that the charger had a green led light on it both before and after I plugged in the battery. I would have sworn the charger had a red led before when I started charging that switched to green when it was fully charged, but I’m not certain.

When I put the battery on the bike and tried to turn it on, there was nothing whatsoever from the control panel. I tried removing it and reinstalling it, turned the battery itself on and off and tried to turn the bike on with both battery settings, etc.

Nothing.

So how does one troubleshoot a Bafang powered e bike? I suspect it may be as simple as a failure of the factory battery, but frankly I’m not sure how to test it with four terminals with two positive and two negative connections.

I’m a mediocre bike mechanic but I have ZERO experience with electrical or electronic systems.

Any help would be IMMENSELY appreciated!
 

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Hi Brian... Long time... I hope you've been well.
You can test across any one negative and one positive terminal as each pole is in parallel. Place your black probe on the first negative and then the red probe on the first positive and then the second. Then repeat with the black probe on the second negative. The readings should be equal across all four tests.
Also test your charger to be sure it has output.
Question.. What SOC (state of charge) (battery %) did you leave the battery at back in September?
Post a pic of your charging port, battery switch and charger.
 
Hi Brian... Long time... I hope you've been well.
You can test across any one negative and one positive terminal as each pole is in parallel. Place your black probe on the first negative and then the red probe on the first positive and then the second. Then repeat with the black probe on the second negative. The readings should be equal across all four tests.
Also test your charger to be sure it has output.
Question.. What SOC (state of charge) (battery %) did you leave the battery at back in September?
Post a pic of your charging port, battery switch and charger.
Thanks. I figured out the battery is completely dead and won't take a charge. I checked it and the charger with the voltmeter. The charger is putting out 54v but the battery only has four volts after charging overnight.

So I just needed to figure out how to replace the battery. It's the older style s039 model mounting plate and it's getting hard to find them.

Ironically, last week I had texted the archery shop where I bought it about the trouble I was having with the e bike and asked if they could help.

He just now texted back. I had put in an order with him for a second battery from Rambo but a couple months later it still was on back order, so I told him to cancel the order. He forgot to cancel it, so he just texted me in reply:
1B3D0977-B20A-43EE-A3C2-60D0C0149FB8.jpeg
 
He’s going to sell me the replacement battery for $200. It’s just a 48v 10.4ah battery but that’s not a bad price at all.

Any idea how to troubleshoot the original bricked battery?
 
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He’s going to sell me the replacement battery for $200. It’s just a 48v 10.4ah battery but that’s not a bad price at all.

Any idea how to troubleshoot the original bricked battery?
Sorry to read about your dead battery that's a bummer. As you have demonstrated the pack cannot hold a charge you may have a bad cell that can't hold current or an unbalanced cell, either way tripping the BMS to shut off the battery.

As you are in Harrisburg, PA, I'd try contacting a couple of local businesses that rebuild battery packs to get a quote on diagnosing and recelling the pack, they may or may not want to just replace the one cell but all the cells in the pack, provided the BMS is not damaged that should return it to a condition where it can hold a charge. Googling around there appear to be a number of businesses near you including Matt Bzura bicyclemotorworks.com in Bethlehem, PA, MTO Battery mtobattery.com in Red Lion, PA, or Vicious Cycle Battery viciouscyclebattery.com in Philly.
 
He’s going to sell me the replacement battery for $200. It’s just a 48v 10.4ah battery but that’s not a bad price at all.

Any idea how to troubleshoot the original bricked battery?
In theory there is a method that can be attempted to revive the battery. It requires measuring the voltage of each cell and then placing any below cutoff voltage unbalanced cells at a low current long charge using a voltage slightly higher then its present voltage. Measuring voltage periodically and checking temperature as well (temperature rise above a degree or two is not good) see if the cell is absorbing any voltage and measures higher.. if so slightly increase the voltage and continue. If you can get all the cells equal and above the low voltage cutoff, it should then take a charge as normal.
This would require a bit of technical skill and a bench top power supply that could be finely tuned to charge. Additionally there is no guarantee that it would be a permanent fix and trying to do this with an assembled pack can be dangerous as it really is hard to know if a cell is damaged internally or what safety measures have been implemented by the manufacturer.
Personally, I doubt that I would attempt this unless it was minimally below cutoff and I was able to set up a safe fireproof environment.
Even then I think I would do a bit more research and seek out someone with greater experience for advice before moving forward.

As for the new battery, whenever you put it away for storage... try to leave it between 45.6v and 48v and then check on it once a month.
I have my typical ride end in this range so it's rarely any extra effort... But then again I'm a boring creature of habit.
 
I suggest you do some Google research on reviving the battery. Many different techniques from as simple as using a second battery to boost the first above the low voltage cutout. I have no personal experience, I just keep an eye on batteries that have set a while. I ride year round, or until it goes below 25 degrees F, so low voltage isn't a major issue for me.
 
I picked up the battery from the archery shop this morning, brought it home, opened it up, and immediately realized the spare battery Rambo sent my archery shop for my e bike last summer is the wrong style battery.

This is my original s039 type battery and mounting plate:
13CB502D-381E-4399-95F6-0A55114EDF3E.jpeg
F3138913-EBAF-4297-8125-B0E95F2818C9.jpeg


This is the battery I just picked up. It’s a r049-2 (or YW 5 pin) type and obviously won’t fit my current mounting plate.
AADFCB32-C94D-470D-A3A1-4406475C528D.jpeg

Neither did it include the correct r049-2 type mounting plate, which looks like this:
7C2A6593-DBAD-4EAC-8668-F50B3E021CF8.jpeg

The batteries are the exact same external dimensions.

How hard would it be to swap the internals of the new battery into the original battery case so it would work with my current mounting plate?
 
I picked up the battery from the archery shop this morning, brought it home, opened it up, and immediately realized the spare battery Rambo sent my archery shop for my e bike last summer is the wrong style battery.

This is my original s039 type battery and mounting plate:View attachment 91044View attachment 91045

This is the battery I just picked up. It’s a r049-2 (or YW 5 pin) type and obviously won’t fit my current mounting plate. View attachment 91046
Neither did it include the correct r049-2 type mounting plate, which looks like this:View attachment 91047
The batteries are the exact same external dimensions.

How hard would it be to swap the internals of the new battery into the original battery case so it would work with my current mounting plate?
Much harder than buying the correct mounting plate 🙃
 
How hard would it be to swap the internals of the new battery into the original battery case so it would work with my current mounting plate?
Then I could try to revive the old battery inards later.
 
Much harder than buying the correct mounting plate 🙃
Yeah, I finally found the correct mounting plate on eBay. Of course I could also buy that spare battery I’ve been talking about and it will come with the correct mounting plate
 
Then I could try to revive the old battery Ibarra later.
All is possible.. at least to try.
But I'd get a new mounting plate way before I tried to swap battery internals. If you ever opened one up, everything is neatly and tightly packed in there.
 
I am not telling you to do this. I am asking that you skim the article and if it looks applicable then do some more research. I have successfully jumped many batteries. If you could save the old one because it went into safety mode, that would be cool.
 
I am not telling you to do this. I am asking that you skim the article and if it looks applicable then do some more research. I have successfully jumped many batteries. If you could save the old one because it went into safety mode, that would be cool.
Luna had serious issues with early batteries. The BMS needed to be flashed. The BMS was identical to the UPP batteries. I suspect that was their source. CRAPTASTIC!
 
I am not telling you to do this. I am asking that you skim the article and if it looks applicable then do some more research. I have successfully jumped many batteries. If you could save the old one because it went into safety mode, that would be cool.
I did try this as I don’t think I had anything to lose, but it didn’t work unfortunately.
 
I did try this as I don’t think I had anything to lose, but it didn’t work unfortunately.
I have heard of people trying something similar with tool batteries with some success, but I've never found myself in a situation to try it.
I had a friend with 2 year old battery chainsaw that was purchased and never taken out of the box... and when he finally did it wouldn't take a charge. I told him to bring it by and we'd open it up and take a look but that never happened either.
He's good for the economy i guess 🙃
 
I did try this as I don’t think I had anything to lose, but it didn’t work unfortunately.
I have heard of people trying something similar with tool batteries with some success, but I've never found myself in a situation to try it.
I had a friend with 2 year old battery chainsaw that was purchased and never taken out of the box... and when he finally did, it wouldn't take a charge. I told him to bring it by and we'd open it up and take a look but that never happened either.
He's good for the economy i guess 🙃
 
There are so many pitfalls for beginners. I’m somewhat experienced but am giving up and selling my welders and related gear. Just to many ways to go wrong.
 
There are so many pitfalls for beginners. I’m somewhat experienced but am giving up and selling my welders and related gear. Just to many ways to go wrong.
I don't think I'd ever want to weld up a pack, or replace bad cells... Too much to match up.. capacity/age/internal resistance.
Replace a BMS or nurse shut down cells... I think I'd give it a go
 
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