Help UPP 48V 20amp Battery

[Deadhead86]

First post here.

I’ll include a couples pics of the battery since taking it apart. It was running great with a 1000 watt geared motor on a my front wheel. Then I changed it to a ebikeling kit after the front motor had about 8k miles on it and I had some issues with it and wanted to try a rear motor.

Thus I bought a ebikeling kit which ran great for about 1k miles, kit is a 1500 watt 26” rear wheel direct drive motor ebikeling kit and UPP 48v 20amp rear rack battery, No Problems. Then it just stopped holding a charge at all.See the pics of what I found inside.

I’ve since bought a new battery a 52v 20amp triangle uPP and everything works fine.

Any advice on how to fix this old battery bc it should still have plenty of cycles left in it. Why would it read %0?

I did email UPP, which is a freaking nightmare, getting a response is hard and they told me to disconnect this little board, which I thought was a BMS at first but Realized that was totally wrong, then realized after further research it’s some sort of voltage meter, is that correct? Could it being in this condition cause the battery to no longer show it holding a charge? or even that it is charged on my ebikeling 900C lcd screen?

UPP had told me
To cut this meter out and charge it without it and it should charge fine? Is this correct too?

Any and all advice on how I can get this wired back correctly and to hold a charge would be great.

One of the pics is the closest thing I could find. But it’s obviously not the exact one, I’m obviously out of my
Depth here and I know this isn’t something I want to be just “winging it”, so I will not be preceding any further until I’m %100 confident and sure on my course of action.

Thank you all in advance for any and all help.


Edit…. I possibly could of made a rookie mistake one time when I asked my step son to plug it in for me, he said he fplugged the charger into the wall first then the plug into the battery! Could this of caused this sort of burning to this voltage board?

Thank you

 

[MattZ]

That's a step down buck converter that lowers the battery's 48v to 5v for the USB socket. Cutting it out won't cause a problem with the battery itself. The 48v from the battery is also going somewhere else since + and - each have 2 wires tied together on the 'in' side of the converter. They likely go to either the battery charging port or the battery charge level indicator LEDs, possibly both. If you cut out the converter snip off the corners of the board leaving the red and black pairs soldered together.
My guess is the converter is shorted and draining the battery, but I'm not an expert so wait to see if anyone has a better idea before trying anything.

 

[Oli.Hall]

Hi,

The board you have pictured is only there to power the USB port on the side of the battery. It's job is to work as a voltage step-down converter which converts the 48V main battery voltage down to 5V for the USB phone charging port. The battery should function perfectly well with this board disconnected.

As it looks burnt out, it is likely that when it failed, it may have drained the main battery cells all the way down to zero which is why the battery won't register as charged on your bike and also may be why it will no longer charge up.

The first thing you need to do is measure the voltage with a multimeter and see if the cells have any charge left in them. Measure the voltage across the terminals marked "IN" on the voltage converter with a multimeter and report back here.

Be very careful not to short circuit any of the wires or the pads on the circuit board as they will have full battery voltage on them. Tape them up securely when you have finished measuring the board.

Sadly if you measure this voltage and it is lower than around 26V then it is likely that the pack is unrecoverable and not safe to use any more.

thanks,
Oli.

EDIT: Sorry I didn't see matt had already replied before I hit submit! - Best thing is to measure the voltage on the input of the converter before you do anything.

 

[Deadhead86]

Awesome thank you OLI. I’ll get back in touch with you later tonight . Heading to work now. But thank you for the advice.