OHZHAO 960mAh TL284443 Battery, 2025 Upgraded High Capacity Li-Polymer Replacement Battery for Nest Learning Thermostat 2nd 3rd Generation, T3007ES, T3008US, T4000ES, A0013 with Repair Tools

Perfect fit. Perfect performance. Saved my expensive thermostat. Instructions would have helped.

I bought this to replace my failing battery. I installed the new one and there appeared to be no charge. So I plugged it in using the same usb cord I using to recharge my current battery and after 24hrs, nothing. I pulled it out, reinstalled it to make sure I did not make an error, same thing. I reconnected my current/original battery and my thermostat booted up.It was great that it came with everything you need to remove the old and install the new, but was a waste of money since it never would charge.

As original battery in unit gets older ofen you can’t access thermostat over wifi.This 3.7V battery fits great and has a higher Amperage.

Battery was not charged and not charging

Before you buy this make sure you watch YouTube video on how to replace the battery. It is not that difficult as in your IPhone or IPad, but it is not as easy as in your TV remote either. If you do not feel comfortable of working with the modern micro-electronics devices with all these tiny screws and electrical connectors - think twice before you attempt to do so.Other than that - it is a proper replacement part with upgrades higher capacity. The set comes with necessary tools to open and close the unit. And the price is better than OEM.