Sizing
How to Size a Home Battery for Solar
Calculate daily kWh, backup days, and inverter compatibility before you buy a LiFePO4 home battery.
8 min read · Beginner
Start with your daily energy use
Add up the kWh you use on a typical day (or use 24h of critical loads for backup-only systems). Multiply by backup days (1–3 for outages) to get a rough storage target. Add 20% for inverter losses and depth-of-discharge limits.
Match voltage to your inverter
Most whole-home LiFePO4 packs are 48V or 51.2V. Confirm your hybrid inverter or charge controller supports the battery BMS protocol before ordering.
Use our calculator
Our free battery calculator estimates pack count from daily kWh and budget. Then compare models in the shop filtered by capacity and Energy Score.
Related manuals & docs
Manufacturer PDFs that pair with this topic.
- OpenmanualEG4
EG4 WallMount All-Weather — User Manual
Full install, paralleling, conduit box, and BMS setup for outdoor WallMount packs.
- Openquick startEG4
EG4 WallMount All-Weather — Quick Start
Fast mounting overview with 18kPV / FlexBOSS bracket notes.
- OpenmanualEG4
EG4 18kPV Hybrid Inverter — User Manual
Wiring, grid/gen ports, battery protocols, and commissioning for the 18kPV.
- OpenmanualEG4
EG4 FlexBOSS18 Hybrid Inverter — User Manual
Specs, mounting, battery terminals, and GridBOSS pairing notes.
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- Best Home Batteries in 2026: How We Rank Them
Our Energy Score methodology — efficiency, warranty, compatibility, and value — explained.
- EG4 WallMount Buyer’s Guide
Indoor vs All-Weather, 280Ah vs 314Ah, and which hybrid inverter pairs cleanly with EG4 WallMount packs.