Yes, a rechargable battery cell is built in the DiMAGE Xt for date/time backup. However, in case the camera is left for a long period of time, the camera is not able to keep the date/time setting if the dedicated battery NP-200 has been removed before storage. When the date/time is reset, settings in the menu are also reset to default. Date format, Video output, language, file number memory, custom audio signals will be kept.