yes. Where would I look for cell packs that would fit in this case? I could install them myself.
Battery only charging partially
- Thread starter Chris Maluszynski
- Start date
Loads on Aliexpress and a few on Ebay. first you need to measure the space inside the case or measure the previous cell-pack.
Hi, please let me know how old the bike is and where the battery is situated on the bike?
All the best, David
The battery shouldn't work at all if #4 is 0v as this cell bank is dead , the BMS should be sensing a fault and refusing to switch to allowing a charge. Also #1 & #3 are quite low so should trigger lvc much sooner.
I for one would be very cautious of this pack and certainly wouldn't continue charging.
Repeat the first four voltage checks incase there was an error in testing .
What ever occurs now don't persist with this cell pack , take it to your local recyling centre for just that recyling .
I for one would be very cautious of this pack and certainly wouldn't continue charging.
Repeat the first four voltage checks incase there was an error in testing .
What ever occurs now don't persist with this cell pack , take it to your local recyling centre for just that recyling .
I actually left it charging , so you got me a bit worried. What could happen?
Unplug the charger, use the battery for an hour or until it stops working then take it to the recycling station. As it is faulty, don't charge it again.
Scary stuff. And now I'm without a bike which I'm very dependent on (I live on an island with no cars, and need to haul everything for 2km on the bike to the house from the ferry).
I do however have a 54V sharkfin battery. If the cells fit in the Wisper case, maybe I could replace the pack? Or would 54V kill the controller on the Wisper?
I do however have a 54V sharkfin battery. If the cells fit in the Wisper case, maybe I could replace the pack? Or would 54V kill the controller on the Wisper?
Don't panic just yet. Do the tests that Neal suggested. Something doesn't quite add up with the measurements you made, so repeat them first before you decide what to do. Nothing has changed from before, and it didn't blow up the previous times you charged it, but do it in the garden rather than your kitchen, just in case.
Don't use the 48v battery on a 36v kit, it will cause even more trouble than your present problem. You only need a modest but new 36v battery.
What??? Putting a 48v battery and controller would be a good solution for any 36v Wisper bike. If I had any 36v bike that had a failing battery, I'd always upgrade to 48v, except in some fringe situations.
It wwould probably damage the controller, but controllers are cheap and you can use the opportunity to get a better one.
Ok. Maybe i even have a 48v controller somewhere. But it would be so much easier to use the one on the bike as I wouldn’t have to switch displays, brakes etc right?
His commute is modest, he does not need a big battery. Even a tool battery may work for him. If it were me, I would hook up a 10ah or 15ah saddle bag battery and sort out his problem in 5 minutes. A bag battery would usually fit inside behind seat post battery cases.
Another measurement confirms the dead cell bank. I guess this means the BMS is faulty also then?
3.3
7.4
11.0
11.0
15.1
19.1
23.2
27.3
31.3
35.4
3.3
7.4
11.0
11.0
15.1
19.1
23.2
27.3
31.3
35.4
David, could you tell us if the controller on this bike would handle a 48v battery?
Take a voltage reading direct off the battery pack from the cell with the thick Black wire to the cell with the Thick Red wire.
If that cell group is dead then the battery shouldn't work and yes looks like the BMS is faulty if the battery is still usable.
If that cell group is dead then the battery shouldn't work and yes looks like the BMS is faulty if the battery is still usable.
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