Recently Bought a SunControl board, I have a Raspberry zero W and a LiPo 6600 mAh battery. Used PIN FEMALE JUMPER TO GROVE 4 PIN CONVERSION CABLES to hook suncontrol to pi. As in picture 1. Use AC 5v - 2 A charger to USB connector on SunControl to charge battery (no sunpanels yet) The new battery was origanally charged at ca. 3.7V and it started charging slowly while I had my piZero running on USB. Output suncontrol. I never?/ hardly saw negative Lipo current values! which is a sign battery is charging, isn’t it? Pi zero used around 130 mA. anyhow, battery did charge up to 4.2V. Nothing became hot, no worrying signs whatsoever. the yellow and green charge light were on at the end.
A few times I closed down the zero but let the charger usb be connected. Red charging light/ power always OK. rest of the leds seemed OK all the time. But after 2-3 days, i noticed value battery bus value gradually dropping, stopping , system closed by itself in the end of course Now battery charging Led still on(yellow). Logical that system closed below 3.3 V but the question is: why did it stop charging?
Please the steps to asses the cause of this (pictures can't be inserted. 37 kB. JPEG)!
“Take the battery to full without a load on the USB output.”….this doesn’t work like I said, with nothing on USB out, the battery continues discharging now and I can’t really see realtime because the raspberry is not connected. I measured battery with multimeter, 2 Volts appro. my wiring is as specified in the specification of switchdoc, which can be seen in picture 1.IMG_3537.psd (187.36 KB)
At the moment I can’t control anything since the batteryload is too low and the battery doesn’t charge with charger on input USB. i enclose some pictures of the set up.
It is *possible* you have a bad SunControl board, but I don't know yet.
Please plug your charger into the board and take a picture of the lights on the battery side of the SunControl board. This will help[ me diagnose the problem. Unplug all of the other plugs from the SunContol board in case there is a wiring problem. I like dealing with one problem at a time!
Again... with these connections everything seems to work originally. Battery loaded to 4.2 Volt. All lights were lit and when battery full also the green battery light. So: red led power good (When USB charger connected) yellow light battery charge green light battery charge (when 4.2V) blue led Watchdog blue led USB Only after this the unloading problem started, and then after battery went low, only battery power good red was lit and battery charge yellow. So with no battery I took this photo. same as with battery: red and yellow light. I hope you have a clue
Ok, I’ll summarize the problem: 1. At first, with battery connected, the battery charged (slowly) to 4.2 Volt. I was able to run testcontrol. All the relevant leds functioned. I had the pi zero connected to USB out ( on SCboard) and running most of the time
2. Then, after a day or two, i noticed the battery losing charge to 3.6 volt and lower. even uncoupling the pi didn’t stop this. The led light were still lit except the green charge led.
3. Some time after ( Logically) the battery stopped the pi and only the led charge and power good led were on.
4. tried several things but nothing worked, also difficult to see when pi zero isn’t coupled with usb out of SC.
So this is situation now, i returned battery to have it checked. Would be strange if the (new) battery is damaged. . Nothing special to see there however. No external damage etc.
OK, that's reassuring but one thing I find not logical:
You say the battery will slowly discharge under load (the pi on USB out). 1.Why did it then first load from 3.7 V to 4.2 Volt withthe Pi on USB? In other words "under load"? 2. Why did it then start unloading even with no Pi connected, even not with trickle charge from USB in? Because I let USB in, connected and powered. In my view it should have restarted charging at some point.
your point 3 ("Correct! The hysterisis on the board protects the Pi and the b artery") is sign of good functioning although I did not check if the Pi was closed correctly (via USB control). Maybe it was a "hard stop" because of V<3.2.
Have a new battery Bought a seperate lipo charger, in case of.. all valurs below have a battery connected to Suncontrol of course Values are averages I tested 3 possibilities.
1 SunControl wiring connected to Pi powered by USBOut, no USB charge, Two blue lights … Lipo load 3.96 ( going down rather fast, 0,01 V per 2 minutes) Lipocurrent 870 Solar load 0,43 Solar current 0 Output load 3.65 Output current 133
2. as 1 but with USB charge connected Two blue lights plus red light power plus yellow light charge Lipo load 3.98 (slowly going down, 0,1 V per 10 minutes) Lipocurrent 630 Solar load 0,87 Solar current 0 Output load 3.72 Output current 130
I still noticed a high Lipo battery current, which should be negative in case the battery is charging, isn’t it? I then shut down the Pi Zero and left everything (wiring and charging) connected for the night. Next morning the battery was completely drained, charged around 1 Volt according multimeter. I recharged battery with a charger (to and then continued with 3. The battery was recharged to 4.19 Volt
3. Suncontrol with no wiring connected charger to usb Suncontrol connected red and yellow charge LED and the 2 blue lights. Of course Impossible to check mA and V during proces. I left it for the night. Next morning the Battery was completely drained! Just red and yellow charge LED.
I think 3 proves it’s not a Pi or a wiring problem. What’s your opinion on this?