• BigBattery ETHOS 20.48kWh + FlexBOSS18 Kit — complete kit product view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
  • BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view

BigBattery

BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter

BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter

SKU: K0232

$7,821.99
$9,365.00
$7,821.99
Save $1,543.01 (16%)

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For in-stock orders placed today. Standard Lower 48 delivery; availability and carrier scheduling may affect arrival.

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Solar Storage & Home Backup

Store your solar, cover essential loads and stay ready for the next outage.

This clearly defined kit pairs 20.48kWh of nominal storage in 4 modular ETHOS batteries with the EG4 FlexBOSS18. It gives homeowners and installers a practical foundation for solar self-consumption, backup planning and permitted grid interaction—without forcing the buyer to decode the battery and inverter quantities.

20.48kWh
Nominal battery storage
10kW battery / up to 13kW with PV
AC output capability
18kW recommended PV
Solar input planning
12 years
Battery warranty term
BigBattery ETHOS 20.48kWh + FlexBOSS18 Kit — complete kit product view
BigBattery ETHOS 20.48kWh + FlexBOSS18 Kit — complete kit product view

Why it earns a closer look

Useful capability, explained in buying language.

Storage sized to the project

20.48kWh of nominal capacity gives the installer a concrete starting point for load and runtime planning.

AC output capability

10kW battery / up to 13kW with PV from the EG4 FlexBOSS18, with operating limits stated separately from battery capacity.

Modular storage that stays organized

ETHOS modules, a control box and the manufacturer-listed stack hardware create a purpose-built battery bank rather than a loose collection of parts.

Use solar on your terms

Compatible hybrid operation can prioritize self-consumption, backup and permitted grid interaction after commissioning.

BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view
BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter — product detail view

Where it fits

  • Residential solar self-consumption and time-of-use planning
  • Whole-home or essential-load backup designed by a qualified installer
  • New or retrofit hybrid systems using the exact documented battery and inverter models

System-fit guidance

The configured battery-bank continuous rating meets or exceeds the combined inverter battery-powered rating; final conductor, protection and surge design still requires engineering review. Grid-tied, hybrid or off-grid operation when configured and permitted correctly

What’s included

  • 4 × BigBattery ETHOS Batteries
  • 1 × EG4 FlexBOSS18 Hybrid Inverter
  • 1 × ETHOS control box
  • 2 × ETHOS bases
  • Manufacturer-listed ETHOS communications, parallel and final positive/negative cable set for this stack size
  • Manufacturer-listed second-stack connection cables

Typically still required

  • Solar panels and array racking
  • Permitting, utility interconnection and installation labor
  • Site-specific conductors, conduit, disconnects, overcurrent protection and grounding unless itemized in a written order confirmation

Frequently asked questions

What exactly comes in this kit?
The currently verified core package is 4 ETHOS Batteries and 1 EG4 FlexBOSS18 Hybrid Inverter. ETHOS grounding cable is not listed as included and must be planned separately. Confirm the final written packing list for SKU K0232 before fulfillment.
Are solar panels included?
No. Solar panels, array racking and site-specific balance-of-system materials are not part of the verified package. They must be selected for the roof or ground array, climate, code and inverter input limits.
How long will 20.48kWh run my loads?
Runtime depends on the loads, reserve setting, temperature and conversion losses. As a simple planning example, 20.48kWh of nominal energy represents about 20.48 hours at a constant 1kW load before losses and reserve; real usable runtime will be lower.
Can this system sell power back to the grid?
EG4 FlexBOSS18 supports grid-tied and hybrid operating modes, but export requires the correct design, utility approval, commissioning settings and local permits. Do not assume permission to sell power back simply because the inverter is capable.
Is the complete kit UL 9540 certified?
Component listings and system certificates are configuration-specific. The exact battery model, inverter model, quantity, firmware and installation must match the certificate accepted by the authority having jurisdiction; this page does not make a blanket UL 9540 claim.
What warranty applies?
BigBattery lists a 12-year limited battery warranty. For the EG4 FlexBOSS18, the current manufacturer materials state: 10-year limited warranty; current written terms control. Eligibility, registration, operating conditions and remedy are governed by the current written manufacturer terms.

Know what arrives—and what the installation still needs.

Send Torven Power your loads, existing equipment and project goals for pre-purchase fit guidance.

Specifications, images and package contents can change by hardware revision. The delivered model label, current manual, written warranty and permitted design control.

BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter BigBattery BigBattery ETHOS 20.48kWh Grid-Tied Battery & Inverter Kit — 4 ETHOS Batteries + 1 EG4 FlexBOSS18 Hybrid Inverter

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