Battery Monitors, what works and doesn't


Why is everyone so hung up on accurately tracking SOC? If a tenth of a percent, or even a few whole numbers off are gonna break your bank then your already pushing it too hard.. I honestly could care less if my BMV is accurate to a thousandth or not, I'm boondocking.. not running a laboratory.. I keep my LFP calibration off intentionally, I dont charge it to 100% SOC but I've got the gauge to reset/calibrate to 100% when its really about 94%.. my low SOC cut off takes this into consideration.. but for my purposes, its 100% charged at 14.4v and its fine.. I get the data I need, power in/out, along with historical comparisons, and a really good idea how much I got left or need to put in.

Coming from the good ole days of 4 separate LED's that read 20%/40%/80%/100% on the control panel I'd say what we got now days is far more than is needed to get the job done, and thats great..
Truly a hell of a lot better than guessing on LEDs. The less I care about mine the better. It doesn't seem to do well at all with my wireless USB/battery(18650) travel router connected via USB (12v->5v step down) and shows a 0w->3-6w->0w drain, value changing every few seconds. I don't really understand it, but if I leave the battery on my work bench not receiving any charge for several days it'll show say..20ah down, when reality is 50ah. I never noticed this in bench testing because I was discharging and then immediately recharging. Guess zero current calibration doesn't work well with whatever pulsing the router is doing. Means nothing when it recharges every day via solar though.