Adding new battery with different installer

We currently have a Gen 1 3.6kW hybrid inverter (with 2.34kWp single string solar array) and two 2.6kWh Gen 1 batteries. I am considering adding a further 5.2kWh (likely also Gen 1) battery to the mix with a different installer.

This is because the original installer (Eon) missold our system as 5kWh usable when it is in fact closer to 4kWh usable, to maximise our self consumption and to give us greater capacity to participate in grid flexibility events - as well as selling more energy to the grid at peak demand times rather than when the sun is highest in the sky.

I have two questions-

• If we make the new battery our master battery will that increase our maximum battery output to 2950 watts (at least when the new fast response firmware comes in) or will we be limited to 2600 watts because of the smaller batteries.

• Will using a local installer to do this work invalidate or in any way affect the warranty on the existing equipment, or are we forced to go back to Eon to do further work (which I would probably then skip).

I think from a GivEnergy perspective your "whole system" is assigned to just one installer, so the new installer would have to take over ownership of the existing installation, and TBH if I were Eon and there were ever a problem they would say it was whatever the new installer had done.

The largest batteries have to be first in the chain so it'll require the existing 2.6's moving to be slaves of the new 5.2. Again Eon would be able to say they can't support it any more. As long as your new installer is happy I don't see this as an issue, your manufacturers warranty still remains with GivEnergy

I think you will still be limited to 2600W as that's a limitation of the 2.6 batteries. Am sure its in the manual but I couldnt find it https://kb.givenergy.cloud/article.php?id=125&oid=1

Do have a look at the cost of the 8.2 or 9.5 batteries, by the time installation costs are included they may not be much more than a 5.2 (which is really a 4.2)

I have a 5.2 1st Gen and a different installer added a 2.6.

The new installers had to accept they are now responsible for both. Not that I would want them back. But that is the way....

The 5.2 is the master and I have 3000w as the setting for export or import into the battery.