Independent research, updated August 18, 2026. Some product links are affiliate. No test lab. How we work
Updated August 18, 2026

Powerwall 3 vs EcoFlow Ultra X vs Anker F3800 vs BLUETTI EP900

Same chemistry class (all LFP). Completely different products. A 3.84 kWh portable is not a 13.5 kWh wall appliance with a gateway.

Powerwall 3 EcoFlow Ultra X Anker F3800 BLUETTI EP900
RoleInstalled whole-homeOrderable whole-home stackHigh-output portableHigh-output inverter + modules
Energy (base)13.5 kWh12 kWh (2 packs)3.84 kWh~9.9 kWh (2× B500)
Continuous W11.5 kW12 kW6 kW9 kW
Motor start (published)185 LRAMfr. surge claim up to 45 kWNot published as LRAHigh; confirm kit
ChemistryLFPLFPLFPLFP
SwitchoverSeamless (Tesla gateway)<20 ms with SHP3Manual / transfer kitDepends on panel kit
Buy pathTesla / certified installerEcoFlow.comAnker SOLIX / AmazonBluetti / Amazon
How you buy itInstaller quoteBrand siteBrand site or AmazonBrand site or Amazon
Price snapshotInstalled bid$7,999–$13,999 list bundles$1,799–$2,000Confirm live kit

Real-world fit

Powerwall 3 wins if you want one wall unit, Tesla app / Storm Watch, and you will pay installer pricing. 185 LRA is a concrete motor-start number, which most portables do not publish.

Ultra X wins if you want Powerwall-class watts and you want to order the hardware from EcoFlow, optionally with their install program. Warranty on the current US page is 5 years — shorter than Tesla’s 10. That is a real trade, not a footnote.

F3800 wins as the first purchase: 6 kW, 240 V, price under $2,000 on sale, sit-on-the-floor, returnable. Energy runs out fast (3.84 kWh is about 2–3 hours at 1.5 kW).

EP900 wins when 9 kW continuous matters more than polish — wells, shops, frequent cycling — and you will stack B500s.

If you will buy this month

Start with the cart product that matches watts, then add batteries. Do not start with Tesla if you need hardware in the garage next week.

Find mine Shop-ready