Pendalton e bike battery
- Thread starter Ash123
- Start date
I'm new to this e bike stuff but , I've checked everything on the circuit board and everything appears ok, plus all cells are good, there's even power going to the on off button, it's trying to determine why the battery charger goes from red to green within a few seconds, maybe there's something on the circuit board sending a wrong signal to the charger saying its charged,
27V is horribly low. That might be something to do with it.
You said you had it apart: did you measure the individual cell group voltages? They should all be close to identical.
You said you had it apart: did you measure the individual cell group voltages? They should all be close to identical.
Ok, so balance is good.
It is possible the BMS is refusing to allow charging because it does not like 27V. The workaround, which carries risks and so should only be attempted if you understand them, is to charge directly to the cells rather than through the BMS until above the low voltage cutoff. Say to 33V to be sure.
Then revert to normal way of charging and see if cured.
Be very careful with the pack open to avoid shorting anything out, and do not leave unattended as there is only you to stop the charge. And charge at a very low rate.
That could be the reason so iv got a low trickle charger directly on the cells., checking every 15 mins making sure everything is going well
If all the ten cell groups are all at 2.7v then the BMS won't allow charging, 27v is too low for a 36v battery . Typically 30/ 31v is the lowest one might see.
The BMS is seeing 27v as a fault and below LVC so one needs to manually raise the cell voltages to 31/32v at least, then the BMS should do it job and the charger will turn red to indicate charging.
The BMS is seeing 27v as a fault and below LVC so one needs to manually raise the cell voltages to 31/32v at least, then the BMS should do it job and the charger will turn red to indicate charging.
Thanks for the info, got a trickle charger directly on the cells in hoping it will kick start it back into life again
Cells will take all day for each one with trickle charger .
I use an old 5v phone charger for charging low cell groups via the BMS sense wire white connetor block at approx. 1a , it will take about 20 -40 mins on each cell to get them up to above 3.1v.
Cut the charger jack off and solder an arduino board pin to each wire end and insulate the end leaving about 6mm of pin showing , then in pairs place them in the sense wire connector having identified the cell group being charged.
I use an old 5v phone charger for charging low cell groups via the BMS sense wire white connetor block at approx. 1a , it will take about 20 -40 mins on each cell to get them up to above 3.1v.
Cut the charger jack off and solder an arduino board pin to each wire end and insulate the end leaving about 6mm of pin showing , then in pairs place them in the sense wire connector having identified the cell group being charged.
This is what I'd do, but only if all cells are above 2.5v.
With the battery open, find the black wire that comes from the cell-pack to the BMS. It should be marked "B-". Find the black wire that runs from the BMS to the charge socket. It's position on the BMS is often marked "C-".
Plug in the charger. Bridge the B- to the C- with a spare bit of wire. The charger should go red. Hold it there for a couple of minutes until the charger keeps charging when you remove it.
If the charger doesn't go red, there is an interruption between C- and the charge socket, like a blown fuse in the battery or charger. You can easily find where the break is by following the 42v from the charger jack, through the charge socket and along the path to C-. No need to guess, your meter will show you.
With the battery open, find the black wire that comes from the cell-pack to the BMS. It should be marked "B-". Find the black wire that runs from the BMS to the charge socket. It's position on the BMS is often marked "C-".
Plug in the charger. Bridge the B- to the C- with a spare bit of wire. The charger should go red. Hold it there for a couple of minutes until the charger keeps charging when you remove it.
If the charger doesn't go red, there is an interruption between C- and the charge socket, like a blown fuse in the battery or charger. You can easily find where the break is by following the 42v from the charger jack, through the charge socket and along the path to C-. No need to guess, your meter will show you.
We had a Pendleton that was sold to us cheap with a supposedly 'dead battery'. It wasn't dead at all. The BMS is likely to be just refusing to charge because the cells have been neglected and have gone too low. Ours was easily mended by charging the batteries directly BUT VERY CAREFULLY . It still works great years later. I charged it very carefully directly on the output pins, monitoring the voltage the whole time. Within ten minutes, the voltage was raised so that I was able to charge it in the proper, conventional way. NEVER EVER DO THIS unless you are familiar with the risks, have a multi meter connected and at least have a fairly decent familiarity in working with electrical equipment.
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Hey guys it's worked by jump starting it, battery charger now on red and charging, thanks for all your help
Fantastic! We were in exactly the same position as you. Bought a bike which was five years old but never used. Battery completely dead. The e-bike ”expert” at Halfords faffed about a bit, read the instructions and came to the conclusion that we’d need to fork out £375 for a new one!
I wasn’t convinced so Googled around, stumbled on your post, thought it made perfect sense and had a go last night..
I just plugged a 12v car charger onto the output pins, in parallel with my volt meter for maybe 10 seconds. Saw a flicker on the battery led, disconnected, plugged in the charger and immediately turned to red!
Can’t thank you enough for posting here. As you say, so much for Halfords experts eh?