should batteries be replaced regularly?

Not at all! Using an appropriate solar batteries coupled to an IMEON inverter and optimally managing their charge and discharge is vital to keeping the storage system in good condition. Some lithium battery manufacturers advertise lifetime of 6000 cycles or more (1 cycle = one complete charge and discharge) at considerable 80% discharge level and announce 10 years guarantee periods. An appropriately sized system cycles once a day, which may prolong the solar batteries lifespan up to 15 years.