Google Nest Learning Smart Thermostat (3rd Generation) with WiFi Compatibility in Stainless Steel and Nest Temperature Smart Sensor (2-Pack) in the Smart Thermostats department at Lowes.com
Nest Thermostat Battery — OneHourSmartHome.com
KML Replacement Battery for Nest Learning Thermostat 2nd Generation Learning Thermostat 3rd Generation Learning Thermostat 3rd Gen T3007ES T3008US A0013 TL284443: Amazon.com: Tools & Home Improvement
Nest thermostat says it has a low battery and won't connect to wifi anymore. Checked the technical info and from what I've read, all numerical values check out that it should be
Nest Thermostat E battery replacement - iFixit Repair Guide