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By dzempel
About 2 years ago I built a weather station based on the Wimp Weather station documented by Nate. To his credit, Nate did a great job detailing the build and I was very successful in building mine and connecting it to my decades old weather instruments. My problem now is that my weather station has recently shutting down at around 2AM and then restarting again when the solar panel starts getting sunlight. To me this sounds like a battery problem as the temperature is about 46 degrees Fahrenheit. Also, the battery voltage is 3.26 volts when I get my last update. As I write this the weather station is up and running and the voltage is 3.35 volts.

So here are my questions; What is the expected lifespan of the PRT-13856 LiPo battery? My weather station is in the SF Bay area and doesn't experience any extreme weather. Has anybody else had to replace their battery this soon?

By jremington
Do you have a battery protection PCB or other circuitry that prevents the battery from being discharged below about 3.2V?

If not, doing so can kill the battery rather quickly.
By dzempel
I'm connecting my battery through the Sparkfun Sunny Buddy - MPPT Solar Charger (PRT-12885) as the build instructions laid out. As I'm just an old retired software person with no electronics background, I've got no idea whether or not this setup includes battery protection. Assuming that it doesn't, is there a circuit that I can easily add in order to insure the battery doesn't discharge below that 3.2 volt threshold?
By jremington
The PRT-13856 LiPo appears to have a protection circuit built in, and should shut off at 2.8V.

So, something else appears to be shutting down at about 3.2V. The Redboard runs at 16 MHz, which is out of spec for 3.2V operation, so it may be failing. You can fix that by using the 8 MHz internal clock rather than the 16 MHz crystal, but you will also need to change the serial port Baud rate and other timing constants to match. This is not a simple task for a beginner.

In any case, if the LiPo voltage drops to 3.2V, it is nearly dead. Either you don't have sufficient sunlight or PV current to keep it charged, or the battery is at end-of-life.