BigBattery FETHS-48051-G1-18-Flex18K-03

Name: BigBattery FETHS-48051-G1-18-Flex18K-03
Brand: BigBattery

92.2 kWh · 33.9–39 kW · Lithium Iron Phosphate · direct PV input · 2 configurations

UL 9540UL 1741 SBCEC listed · Apr 13, 2026

Overview

CEC Energy Storage System List

FETHS-48051-G1-18-Flex18K-03: 92.2 kWh nameplate energy; 33.9–39 kW continuous; lithium iron phosphate; accepts solar panels directly (DC-coupled).

CEC Energy Storage System List · 2 listings

Model	Energy	Power	Grid voltage	Round trip	CEC listed
FETHS-48051-G1-18-Flex18K-03 {208V}	92.2 kWh	33.9 kW	208 V	—	Apr 13, 2026
FETHS-48051-G1-18-Flex18K-03 {240V}	92.2 kWh	39 kW	240 V	—	Apr 13, 2026

CEC Energy Storage System List

NLR PVWatts v8 · Cali-Graf calculation · CEC Energy Storage System List

Solar array size that refills the battery from empty in one average day, before the home uses any of it (NLR PVWatts v8, 20° south roof).

CEC Energy Storage System List

UL 9540 certifies the whole storage system; UL 9540A is the fire-propagation test that fire codes ask for indoors and near walls.

CEC Energy Storage System List

How much energy does the BigBattery FETHS-48051-G1-18-Flex18K-03 store?

92.2 kWh nameplate, per the California Energy Commission list.

Is the FETHS-48051-G1-18-Flex18K-03 UL 9540 certified?

Yes — the CEC list shows UL 9540 certification (certified by intertek).

California Energy Commission — Energy Storage System List, data as of Oct 7, 2026. Manufacturer-reported values confirmed by CEC against certificates.
NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Riverside, Santa Clarita, Chula Vista, Huntington Beach.
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).