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Worth noting that your battery (assuming standard auto/marine/deep cycle - which like to be at 100% charge as often as possible) will begin to slow down on what it can accept from any charge source as it gets more full. So say you're running a 25 amp (~300w) 12 volt charger on your generator...

Thanks, been researching since posting and have spent most of my time in that thread and links. Should be doable either with bluetooth or directly monitoring via pins, hard work already done in many githubs. Can get a 30amp 4s BMS for about $40 so total cost would be maybe $50 to be able to...

Anyone ever used one of these BT BMS units? A lot of them seem like junk visually and are often for more than 4S batteries, but I've seen a couple. I write mobile apps (iOS and Android) for a living, mostly Bluetooth LE stuff at this point including firmware for microcontrollers so apps can...

Q1 would depend on...everything Q2: with a new 90 amp hour non lithium battery, you have ~45 amp hours of usable power before you're deeply discharging it which will affect its longevity. My giant fridge/freezer combo (62 quart) consumes 29 amp hours in 24 hours - 36*F both compartments, in...

Never understood the appeal of these portable ground deploy panels all over amazon that always come with some undesirable charge controller affixed to the back of the panel. I've seen youtube videos of people setting their battery boxes behind these units but what a pain in the ass that would...

Thanks John, will stay within those values. BMV is hooked up and configured, calibrated, and finally managed to reset the history from the old battery (had to do it on the actual device) If I had a means of measuring the actual balance current with a meter on the high cell lead, I'd tell you...

So no significant throttling of current happened on the original two cells that were pegging 3.59-6v (the set charge voltage per cell on hobby charger), but did when the other two cells which had previously lagged behind jumped to 3.6v, and at that point current was greatly reduced (down to like...

Charge up and balance finished, all four cells holding 3.46v and 0.002v match. ?

Yeah quite a bit apparently. The cell sitting at 3.6 that was previously one of the low cells, was sitting at 3.56v several minutes after I unplugged the charger. So I'm guessing it's full to the brim, and I would have expected the other two to be full too from sitting at 3.6v for countless...

Thanks, not sure how I'd do that with a max charge of 14 amps - BUT the cells, after a brief rest in parallel from their puny parallel charging, are back in series. All cells have kissed 3.6v at this point, but not simultaneously. A strange thing happened - cells 2 and 3 were the ones that...

The cells have been in parallel for over an hour (since my last post at the end of page 2). I initially set the parallel charge to 10 amps (which was showing 3.5v out @ 35w) but was increased to 14 amps (the max charger can do) 30 minutes ago. The entire time I've had the pack connected in...

Yea, I know the bleeding they do in the home stretch (combined with reducing current) can make it take forever, I was anticipating that last night. But I didn't really have any solid indicator that it was ever getting to that point other than the drop to 10 amps from the set 13 amps, after eons...

Yeah that's the thing, I couldn't get two of the cells to even 3.45v while the other two were 3.55-3.6. They were certainly higher this morning than they were when I went to bed (like 3.41 to 3.43-3.44 or something) but the other two cells were still hanging out practically at 3.6v and the...

Then paralleled to settle down to resting together, since you don't have a 1S input right? If you did, then parallel charge at 3.55V, later up to 3.6V, seeing how they settle to resting after each new plateau. I guess I do, the hobby charger i'm using is 1-6S and can charge without balance leads...

I'll have to check them out when I get home. That'd be exciting if they unfk't themselves. Never knew that was a thing...

Guess I missed that in battery building 101. I thought the only point of paralleling cells destine for a series setup was to get them to match voltage wise, so that they could then be connected in series. Too much deviation for even connecting in parallel, then manually discharge the high cell...

The cells started out at 3.06 - 3.07 out of the shipping box. I forget what they were with a higher precision multimeter, but they were all pretty much equal. So I put them in series and began charging them up as a 12v pack. No BMS in the mix currently, this was being done with a hobby...

Thanks, I was wondering if my charge rate was too low. Summary of what happened since I can't quite wrap my head around it and maybe your quote above tells the tale... Charging went on at a full ~184w (13a) for 9 hours before I went to bed last night. Cell voltages were Cell 1: 3.41, Cell 2...

Thanks for that clarification, do you still stand by 3.4v/13.6 for fluctuating and underpowered solar setups? Saw you post that in another thread recently. Pack is still charging up at 184w and not behaving like I was expecting. My current house battery isn't a good reference point since the...

How are you going to mount those panels? I think everyone on here is going to say flexibles are junk, maybe not as big of an issue if you're only putting them in the sun occasionally. But then you'll have to build some sort of skeleton for each panel that can fold up, not blow away, and resist...