Battery datasheets quote amp-hours; system designs often end in watt-hours. This guide walks through the battery capacity converter (Wh to Ah): energy in Wh, nominal voltage, and the Ah capacity to match on price lists and install quotes.
Benefits
- Rated Ah = Wh ÷ bus voltage.
- Normalize kWh rack specs to 12 V, 24 V, or 48 V Ah shopping lists.
- Compare vendor Wh claims to Ah listings before parallel/series layout.
How it works
- Enter pack or bank energy in watt-hours (or kWh × 1,000).
- Add nominal system voltage your inverter and loads use.
- Read equivalent amp-hour capacity for bank sizing and SKU selection.
FAQ
How does a battery capacity Wh to Ah converter work?
Ah = Wh ÷ V. A 4,800 Wh (4.8 kWh) target at 12 V → 400 Ah bank. The same 4,800 Wh at 24 V → 200 Ah. Capacity in amp-hours always depends on voltage—state both when quoting installs.
Can I convert a 5 kWh home battery spec to Ah?
Yes: 5 kWh = 5,000 Wh. At 48 V nominal → 5,000 ÷ 48 ≈ 104 Ah equivalent. At 12 V that would be ~417 Ah—same energy, very different wiring and BMS. Match voltage to your architecture, not the marketing photo.
Does chemistry affect Wh to Ah conversion?
The formula Ah = Wh ÷ V is chemistry-neutral. LiFePO4, AGM, and NMC differ in usable DoD and cycle life—not in this math. Apply chemistry after rated Ah: LiFePO4 may use 80–90% of rated Wh; lead-acid often 50%.
Technical specifications
- Bank Ah = total_Wh ÷ bus_V.
- kWh → Wh: multiply by 1,000.
- Usable Ah target ≈ (usable_Wh ÷ DoD) ÷ V.
- Related: battery-bank-size, ah-to-wh, battery-cost.