The Jitterbug Flip battery lasted in tests over ten hours on a voice call. However, we would venture to say no one talks on the phone that long. The battery remains charged to some degree over several days if unused, and GreatCall recommends charging every day or night, so a low battery is never an issue. Jitterbug Flip’s battery is easy to replace, and you can buy a new one if the battery stops holding a charge. The lithium-ion battery lasts from 18 to 24 months.