How To Access Google Nest Thermostat 3rd Gen Lithium Ion Battery TL284443
You can get an aftermarket replacement battery on Amazon https://amzn.to/3czamlf or eBay https://ebay.to/3i0cqnC
Unforturently there is no genuine replacement battery available for sale on the market, so you'll have to settle with a reduced capacity (1.41Wh aftermarket vs 2.1Wh genuine) battery as a replacement.
It's still better than a dead battery though.
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