A:Answer Hi there, Laurie. Thanks for your question. The Nest Cam (battery) uses a rechargeable lithium-ion (Li-ion) battery. It comes with a built-in 6 Ah (Ampere-hour) Li-ion battery, which is not user-replaceable. If you have more questions and other concerns, we recommend reaching out to our dedicated team of specialists on the Google Help Center here: https://support.google.com/googlenest/gethelp