DIY High Cell Count Balance Charger for Cheap

[docware]

I find it hard to believe that your cells are within 1.5% after repeated use and charging cycles.

It´s no problem to have cells within 0,1 % (3 - 4 mV) after 2 years running the pack without any balancing. But those are gently utilized true original Sanyo 18650 cells, not heavily used Lipo. Battery has simple BMS. Charging usually to 4 V max, seldom 4,1 – 4,15 V.
Voltmeter need to have 0,1 mV resolution if you want to measure real cells voltage. In my opinion, there are probably lot of innacurate measurements leading to wrong conclusions, thanks to non suitable measuring equipment.
By the way, Cellog8 accuracy is also not compliant. Inaccuracy is 8 – 12 mV, moreover Cellog is supplied from some cells, this further increases inaccuracy.

 

[elhnad]

Create standalone 10S half-packs,

Connect the two in series for 20S usage.

I like this idea, but i'm kinda newish to this so i can't picture how or what size connector and guage wire you would need for something like this. is there some link to a video tutorial or "instructable"

i don't think i'll go above 14s so maybe 2x 8s hobby chargers would work, but with less series and less voltage, i'm needing thicker cables.

 

[SaabGuy]

youd need to make a harness to connect the two packs for use in the bike. for series youd connect the + of one pack to the - of the other and then the remaining + and - are your overall pack leads. just use whatever gauge the leads on the batteries are, or one step larger (smaller #)

for charging, just remove your harness and connect the 8s batteries and balance cables separately to their own chargers.