Hello dear municipality, I have a transit custom Bj 2014 155 Ps, which is extended to the camping bus with solar system. The starter battery is now over 10 years old and is to be replaced by the existing AGM supply battery, which is then to be replaced by a litium battery. Who knows if my previous battery management is sufficient for this? A MT RE 140 Duo Relay 12 V 140 A with a turn-on threshold 13.3 V and turn-off threshold 12.8 V as well as for the S olar system a so-called sunsaver (see photo). According to my information it could be that with the lithium battery something else is needed here. It is by the way no 230 volt system installed – I don’t need. For technical advice I thank you already in advance. Bernd