A2B 36V Battery Board Fried

[maatsche]

Hello everyone,

I was given an old ebike which didnt work.

After troubleshooting I narrowed down the fault to the battery board which is included in the internal housing of the stock battery.

It would charge but wont provide electricity to the controller.

On the board I found a burned out component. Im not sure how to work on the board because its covered with some transparent sealing material. The cells appear to be fine at the moment.

Do you know if and where I can find any compatiple kind of replacement board?

Would love to start the summer with this amazing bike

Thanks so much in advance.

Best regards,

Marcel



View attachment 2

View attachment 1

 

[fechter]

I didn't see which part burned. Its possible it could be fixed. First be sure all the cells are in the healthy voltage range. One bad cell group with low voltage would cause it to shut off. You can measure on the white connector between adjacent pins.

It will be very hard to find that part. You could try A2B, but I doubt it.

You could most likely find a generic chinese BMS that would do the same job fine, but you would need to do a little rewiring.

 

[RedddieNL]

I have a burned board/BMS on my A2B Shima Battery. It has a keyfob to startup.

(I tried contacting A2B for a new board, but they denied, They said I had to buy a new battery)

It still charges using the original charger, but output voltage is only 5 volts.
Yesterday I tried connecting the 41,5 volts from the battery directly to the bike, bypassing the board/bms.
And it worked, I could start the bike using the keyfob, and also run it.
The only downside is that there is no battery information displayed, the bike thinks the battery is empty.
(One flashing bar is displayed)
Apparently the Canbus system is used to send battery status information to the bike.
I will now order a new bms to replace the old one.

 

[miro13car]

ReddieNL,
you dont want to use Cycle Analist for all those battery info?

 

[fechter]

ReddieNL,
you dont want to use Cycle Analist for all those battery info?

He would still want a new BMS. Bypassing it would defeat all of the protection features.

 

[RedddieNL]

ReddieNL,
you dont want to use Cycle Analist for all those battery info?

He would still want a new BMS. Bypassing it would defeat all of the protection features.

Off course I will install a new BMS, I only bypassed it for testing purpose.
The speedometer, lights and power settings switch works no problem.
I might install a seperate battery status display if needed.
I replaced my old 2200 Samsung cells (which only had 1800 when fully charged) with 3200 Panasonic cells.

 

[maatsche]

Thanks heaps for your reply.

I already located a burned part on the board but have trouble working on the board at it has thick transparent paint/rubber coating

Where would i be able to buy a reasonably priced oem/generic replacement board for the battery (BMS?) ?

Any links/contact details are appreciated.

Thanks in advance!


Best,
Marcel

 

[2WheelsMovesTheSoul]

I think I still have a functional BMS for the original release date A2B Metro some where in a parts bin.

Lemme post a pic tomorrow, if it fits, I'll give it to you for free.

Just cover the postage.

 

[2WheelsMovesTheSoul]

View attachment 3

 

[markz]

Two things

Solder splash by the orange fuse
Something ripped off by the screw near the fuse.

Does that board balance the battery?
The long white connector, looks like some heavier guage wires in there, thats why I question.
Plus bundles of wires off that white connector going to different locations.
I dont know, I think its just a board for the different features of the bike. Speedometer, generic battery level, whatever else you got going on.

That board looks like it has some thickness to it with the plastic underneath. Probably to protect the through hole components from shorting out.

Two black wires by the chip with lots of pins, probably shorting.

Right side fet, looks like a sideways solder peak on the middle pin.

There is something strange about your first pictures you posted, and the second.
The first is much cleaner.
The second is damaged in places, as mentioned.

 

[fechter]

I think it looks fine. They use a funky thick clear conformal coating to waterproof the board. I don't think there's a solder splash.

The balance wires go into a sleeve so it looks like a cable, but they are pretty typical looking balance wires. I have one of the same boards around here somewhere, only for the rear battery so it's slightly different.

 

[2WheelsMovesTheSoul]

Two things

Solder splash by the orange fuse Nope.
Something ripped off by the screw near the fuse. Nope.

Does that board balance the battery?
The long white connector, looks like some heavier guage wires in there, thats why I question.
Plus bundles of wires off that white connector going to different locations.
I dont know, I think its just a board for the different features of the bike. Speedometer, generic battery level, whatever else you got going on. That's correct. You don't even know what you're talking about. Feel free to speculate some more though.

That board looks like it has some thickness to it with the plastic underneath. Probably to protect the through hole components from shorting out. That' called aluminum, and in the biz, we call that a heatsink.

Two black wires by the chip with lots of pins, probably shorting. Nope. Does your DMM work on jpg's? I gotta get me one of those...

Right side fet, looks like a sideways solder peak on the middle pin. Coooool, still works.

There is something strange about your first pictures you posted, and the second.
The first is much cleaner. Its called better lighting.
The second is damaged in places, as mentioned. Nope.

LOL, it's a free working BMS for an A2B. Quit trying to speculate, " I think its just a board for the different features of the bike. Speedometer, generic battery level, whatever else you got going on " you CLEARLY have never owned or worked on an A2B as there was no speedometer on the first model of A2B and the battery level LED's were in the throttle.