Comment by mikestew
I see that the cheapest Ember is now $130. My first-gen is about six years old, and the battery is about shot. I hesitate to drop another $150-ish on a new mug, but OTOH, is consistently hot coffee worth $25/year? Yeah, it probably is to me, so I'm going to have to suck it up soon.
You can buy only a replacement mug (without coaster/charger). Also, get in contact with customer support mentioning the battery, they usually offer a discount code.