I built a small 24v system based on Will's plans from a few years ago: 8 100w solar panels, epever solar controller, giandel 2000w inverter and four battle born 12v/100 Ah batteries wired series/parallel to yield 24v. . I'm using it off grid in a small cabin. Here's my problem: even with a very small power draw, the batteries have shut down twice. Battle Born says I have to charge them up individually so that they are balanced. I did that once, but they just shut down again. It appears that the individual battery BMS is shutting down two of the four batteries and I can't get the system to turn back on to charge using solar. Of course I can go charge them again, but it feels as if I need a real BMS to keep the batteries working right. Is there a BMS that would work for 12v batteries like these? Am I missing something? It is possible, but surprising, that the system would shut down due to low sun in these dark winter days. But why do the batteries shut down so that I have to recharge every time there is not enough power?