In many installations, a battery can be added later, but feasibility and cost depend on the existing equipment. Don’t settle for a general assurance that the system is “battery-ready.”
Ask them to specify which battery models the particular inverter supports, whether an additional software license or equipment is required, and what capacity limits apply. Alternatively, a standalone battery inverter on the AC side may be considered, provided it is suitable for the installation.
From the outset, it’s worth planning for the installation location, cable routes, space in the electrical panel, and the ability to measure consumption accurately. If you want backup power in the future, the loads to be supplied should also be discussed and separated.
Before the upgrade, the applicable connection terms and required procedures should be checked. Today’s technical compatibility does not guarantee that every battery will remain commercially available in the future.
Read also: adding a battery to an existing photovoltaic system.