It’s similar to his design but without the smart features which I didn’t really need.
I’m happy it brought my charging time down to around 100 minutes and has the option of lowering the charging current and putting less stress on my battery. I can also use it as a simple power supply up to 48v and 5 amps.
I bought the parts on amazon and designed and printed the case.
One thing I want to point out with these CC-CV supplies (I use one too), is that they do not follow proper lithium charging protocol. In fact most charge BMS will cut these things short. It’s a good idea to test if yours does this.
Reason: A lithium charger maintains a constant current until it reaches a certain voltage, then drops the charge current accordingly until it goes to net 0… Voltage never exceeds full cell capacity, and the amp taper off starts rather early. These buck supplies do the same thing, except they try to hold on to the CC part way too long. For example if set to 42V 4A, I’ve found quite a few of them will exceed 42V to maintain the 4A current, then start dropping off, but it will still prioritize 4A over voltage, often triggering the BMS to shut the charge down, and often not allow the idle period of balancing to happen either… I have to set my buck supply to 0.4A charge current after BMS kills the charge to restart it and finish balance. Something to think about and look into.
I just watched it closely and it started to reduce the current as it approached 42v (around 41.6v), eventually stopping around 0.060A which is I’m assuming the balancing current because my BMS has a balancing current of 60mah. After a while of that it then went to around 0 A. I think it’s ok but I will have to look into it more. Thanks for the info
I have a small pile of these Ruideng DPS/DPH units and have emphatically not found this to be the case. Is your experience with these particular types of units?
That particular one no, for what it’s worth it’s not much of an issue with packs that does not require much balancing effort. I still charge my boards with em and they come out no problem. I noticed it while diagnosing worn out packs and trying to fix P groups with bigger variation between voltages
Thanks for the link! I’m trying to find a 4A - this shipping is crazy :(. Still waiting on parts for my first build, but want to order a charger soon so I’m not sitting with a deck and no way to juice it up. Those cheap $20 2A chargers cause any harm to a battery pack?
thats a long time, safe to do overnight while i sleep? or should these really be done under supervision? Maybe throw a smart plug to turn it off at the 8 hour mark?
how long we talking here? say with a 12S4P of 40Ts