As electrician I install PV systems and the Chinese have nice battery+inverter combos. Inverter feeds the battery at 480V@10A DC and then the battery later delivers 3-5 kW back over the inverter. Batteries are modular and can go up to 50 kwh. 10kW rated inverter with ~10 kWp panels fully charges 10 kWh battery in couple hours and produces additional 40-50 kWh on a sunny day (southern Germany). Probably the advantage of these products is high voltage and system integration. Sadly I have no good advice for your setup.