u/Legitimate-Dingo-948

I currently have a 6kW system with a Ziewnic Lenox 2.0 inverter and ~5 kWh Ziewnic lithium battery. The system mostly runs off-grid, and grid only kicks in when the battery is low.

In winter, the battery easily lasted the whole night with ~200W load.

Now in summer, my night load has increased to ~300–500W (no AC — AC runs on grid), and the battery drains before morning.

Would adding another identical battery (in parallel) solve this issue, or should I consider other upgrades?