EG4 FlexBOSS21 & OutBack EnergyCell 5 ESS Bundle | 16kW Inverter + 20.48kWh Battery Stack

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$11,178.78

$11,178.78 - $11,178.78

$11,178.78

$9,779.77

$9,779.77 - $9,779.77

$9,779.77

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Description

Energy Storage Bundle | EG4 + OutBack

16kW of FlexBOSS21 Power on a 20.48kWh OutBack Stack

EG4’s FlexBOSS21 hybrid inverter (16kW continuous, 21kW of PV input) paired with OutBack Power’s EnergyCell 5 four-battery stack: 20.48kWh of IP65-rated LiFePO4 storage with the BMS, junction box, base and 4/0 battery cables included. A scalable whole-home ESS that installs indoors or out.

20.48kWh Storage

16kW Continuous Output

IP65 Battery Stack

Secure Checkout

Everything in This Kit

Component	Qty
EG4 FlexBOSS21 Hybrid Inverter	1
OutBack Power EnergyCell 5 Battery (48V)	4
OutBack Power BMS & Junction Box	1
OutBack Power EnergyCell 5 Battery Base	1
4/0 AWG Battery to Inverter Cable Set, 72in (Red + Black)	1

Why Buy It as a Kit

High-Output Hybrid Inverter

The FlexBOSS21 delivers 16kW continuous with 21kW of PV input and 200A grid passthrough, and parallels up to 4 units.

Modular OutBack Storage

The EnergyCell 5 stack identifies and addresses its batteries automatically, with active balancing across the stack.

Indoor or Outdoor

The battery stack is IP65 rated and the FlexBOSS21 is outdoor rated, so the system fits a garage wall or an exterior pad.

Cables Included

The 72in 4/0 AWG battery-to-inverter cable set is in the bundle, not an extra line item.

Kit Specifications

Inverter Output	16,000W continuous, 120/240V split phase (FlexBOSS21)
PV Input	21,000W, 600VDC max
Grid Passthrough	200A
Battery Storage	20.48kWh LiFePO4 (4 x 5.12kWh EnergyCell 5)
Battery Charge / Discharge	5kW continuous
Battery Rating	IP65
Battery Management	Active balancing; voltage, current, temperature monitoring

Documentation & Downloads

FlexBOSS21 OutBack Bundle Spec Sheet (PDF)

Genuine Equipment

Every component is genuine, with full manufacturer warranties.

Kit Support

Our team helps with sizing and setup questions before and after you buy.

Secure Ordering

Order online with confidence, with real people behind every shipment.

Frequently Asked Questions

Are the battery cables included?

Yes. A 72in 4/0 AWG battery-to-inverter cable set (red and black) is included in this bundle.

Can I expand the battery stack later?

Yes. The EnergyCell 5 system supports automatic identification and addressing for multiple batteries, so added units register without manual addressing.

Can the system be installed outdoors?

The EnergyCell 5 stack is IP65 rated and the FlexBOSS21 is outdoor rated; follow each manual for your site conditions.

Is this genuine brand name equipment?

Yes. Every component is genuine manufacturer equipment with its full factory warranty, sourced through authorized distribution.

Do you offer price matching?

Yes. If you find the same item advertised for less by another authorized dealer, reach out to us and we will do our best to match it.

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