I have been having a similar issue with my setup using brick chargers. My 10s pack would only get up to 41.8 or 41.9 and the charger would switch off and the green light would come on. At first I wasn’t sure if it was the BMS limiting the charge or the chargers. So I got a Lab power supply with CC and CV variable output up to 60v and 5a, connected that to the charge port and set it at 42v and 5a and with that I was able to charge my pack to a full 42v. So I have concluded that the brick chargers just can’t do the job completely. Since I am using five 2s Lipos in series and they are easily replaced, I am more concerned about getting maximum performance and range than longevity of the batteries.
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Hmm ok interesting to know. I just find ita bit strange in my case because I’ve never had issues in the past with this charger when charging to 100%
You need to measure the voltage of each individual pack, if one of them has a lower or higher charge than the others then the pack is unbalanced and a regular charger would have a hard time keeping charging constant, you would need a better (more capacity) charger as stated by @Namasaki
The other option would be to manually balance each individual pack, after you do that, you will be able to charge fully 100% 42v with just a regular brick charger
Thanks for the input. I’ll pull the battery apart tonight and test the voltage on each pack. Fingers crossed I’ll just need to manually charge each pack to balance them out again.
Facing the same issues. Charging only to 90%. Which would be an alternative charger, but not ridiculously expensive as a lab power supply 
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Background info. Enertion Space cell 3 and as well the slow as fast charger do this … Other space cell 3 is still charging fine with the same chargers
If you guys take appart your batteries you will see there’s one invidividual pack with more voltage than the others, this was my battery a couple of nights before on my 10S4P with Samsunh 25R and Battery Supports 37V 60A BMS.
Pack 1: 40.1 Pack 2: 40.0 Pack 3: 40.1 Pack 4: 40.1 Pack 5: 39.9 Pack 6: 40.2 Pack 7: 40.0 Pack 8: 41.9
As you can see the last pack has way more charge than the others, I have no idea why this happens, but BMS sees the voltage on everypack and if some of those reach 42V it stops charging, even though the 42V as a full pack hasn’t been reached, in order to protect the higher cells from overcharging.
I left the board on overnight with the charger plugged in and at the next day the board had 100% charge again, when it reached 100% the charger still had the red led indicating it was still working/charging/balancing. This time BMS did it’s job, but I still need to check the voltage of each pack again.
Note that the battery supports BMS has a very low balancing current (less than 100ma) so the balancing process is bound to be very slow.
Some BMS modules like the one from Bestech will keep your cells close to balanced during discharge. I don’t know if the battery supports does but if so, it would be a good reason to not bypass during discharge.
If balancing during charging is good enough, I don’t see a point to balance them during discharge, at least not as importantant as charging
Maybe not as important, and definitely not when using a hobby charger because of their excellent balancing ability. But as we are finding out, onboard BMS circuits do not seem to have as good of a balancing circuit as hobby chargers. At least that has been my experience even when using a quality BMS. IMO, that makes keeping our cells in balance all the time more important.
Then again, when I think about it, how do I know my BMS is keeping my cells balanced during discharge and it’s not just that they’re depleting evenly because they are well matched?
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What BMS do you have @Namasaki? BMSs with discharge balancing are extremely complex as they need a processor to read in all the voltages and open and close switches in order to keep cells balanced. How much did you pay for it?
I think he has the Bestech BMS, pretty good one but not available in USA just China, so shipping/waiting is always a PIA, it’s kinda pricy but a good buy IMHO
This is the one I use. The sales Rep told me that they keep the batteries balanced continually when it’s turned on. I have noticed that when braking down a steep hill on a full battery and watching my voltage meter that the voltage would climb but not go over 42.3 and when I let off the brakes and coast the battery would step back down until it got to 41.9 where it would stay.
http://bestechpower.com/37v10spcmbmspcbforli-ionli-polymerbatterypack/PCM-D223V1.html