Hyena said:
I've done away with charging mistakes by using andersons in the above configured method and not charging on the bike. The bike has an 8 pin series discharge lead hanging off it and the charger has an 8 pin parallel plug. Using the d sub plug is supposed to stop the problems of getting your balance taps mixed up, but only if you remove the discharge lead first! (which is now impossible to stuff up for me because I remove the batteries from the bike to charge)
What Methods says is right though, if I was starting over I'd hunt around for a suitable power supply, or better still pay a few bucks extra and get one of the neat metal case bmsbattery chargers ($53 for a 400w charger set to what ever voltage you need)
The problem arises when you include the balance taps in with the swapping. Ideally you want to always parallel packs at the cell level, both for charging and for discharging. That way each group of paralleled cells act like one big cell because as soon as they are connected, the voltages will equalize to the same level. Stronger cells will "help" the weaker ones and slight variances tend to average out. They will stay balanced better this way as well.
If you must use an integrated RC charger/balancer, like the 1010B, you really need to use a connection system that puts all the balance taps in the same connector as the main power leads. That way, when you swap connectors around, to turn a 20s2p setup into a single 10s4p configuration for charging, there's no chance of screwing up by leaving the balance plugs connected one way, and the main pack leads the other.
A still better solution, in my opinion, is to simply leave the packs in the discharge configuration all the time and then use an external supply, or supplies, to charge the whole pack. With a 1010B set for 10s, it can only manage about 5A of charge current so to do a 10s4p pack it will take over four hours to fully recharge the whole setup. With a hundred dollars worth of external supplies, you could cut that time down by at least 2/3.
I purposely did the balancers so that they are self-contained and completely independent from the charger/supply setup. Each balancer plugs into a single balancer pigtail coming from the LVC/parallel adapter board. There's no order they have to be in and it doesn't matter if you leave the main pack leads connected in series, or re-connect them in parallel, as long as you have a balancer for each 6s (or 5s...) block. Here's an illustration of what I mean:
View attachment 24s2p Discharge-12s4p Charge Setup.png
This arrangement lets you discharge the four 6s2p groups all in series, in a 24s2p 88V/10Ah configuration, but charge it as a 12s4p 44V/20Ah arrangement. This is done with a simple set of four Andersons. The trick is you need four balancers, if you are going to balance them at the same time as when you charge the packs. If the packs are reasonably well balanced, you could charge them all at once, as shown, but then hook the balancer(s) up after they've been charged. In this case, the LEDs will all lit up green and the shunts will be fully on. They will drain off to where the shunt cuts off and the LED turns red. At that point every cell will be at about 4.11V. That way you could actually get away with using a single balancer, but it will take awhile to do all four 6s2p groups.
The point is is you don't need to worry about paralleling the balance plug leads for charging/balancing, like you do with trying to use a single RC charger to charge a 20s or 24s pack setup as 10s or 12s.
I finally got my four MeanWell S-350-24 CC/CV supplies. I will test one in a bit, to see what the voltage adjustment range is for this model.
-- Gary
) but it would work.
