Hello, we have a small RV with which the radio is connected to Dauerplus. As a result the radio can also be used on the place. However, the battery seems to discharge relatively quickly. After 3 to 4 weeks the battery voltage has already dropped to a low level. I think that the current will not be all too large. Therefore, I could imagine that a small solar panel is optimal for maintaining the charge. There is also the possibility, since Perhaps someone has already gained experience and can recommend something to me.