I have for a few months been using ESP8266-12E to monitor temperature, humidity, battery voltage and posting the values on ThingSpeak. I have several ESP doing this, some using the 'sleep' command, others just 'delay'. They are directly powered by 3.2V LifePO4 batteries. As a rule, everything works fine for a week to 10 days, then the ESP stops connecting to the web and drops from STA mode to AP mode. The program still runs (as indicated by the blue led flashing that I use as a 'heartbeat' monitor) I then need to re-start the ESP at ip 192.168.4.1 and reset the SETTINGS ssid & password, then everything is ok again!
Any idea why? Suggestions?
Thanks,
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