Can lithium and lead-acid batteries share the same bus?

[can I mix lithium and lead acid batteries · mixed chemistry battery bank] Generally no. Their float voltages, charge acceptance characteristics and recharge behaviour are incompatible, and a single charge regime cannot serve both correctly, the lead-acid will be under-charged or the lithium over-held at full state of charge. During a staged replacement programme, either separate the buses with independent charge control or accept that one chemistry is being operated outside its optimum for the transition period, and plan the transition to be short.