I have a solar setup with a Growatt SPH 10000TL3 BH-UP Hybrid Inverter and 3 x 2,56 = 7,68 kWh ARK HV batteries, and I am planning to expand the battery capacity, initially to around 25 kWh. I am looking for a DIY solution, as these ARK HV batteries are fairly pricy.
In that connection I have...