EG4 Wallmount 280Ah Indoor Battery & FlexBoss18 Hybrid Inverter (ESS) | 14.3-57.2kWh | UL9540 | Grid-Tied Home Solar System (18kW-36kW PV)

EG4 Wallmount 280Ah Indoor Battery & FlexBoss18 Hybrid Inverter (ESS) | 14.3-57.2kWh | UL9540 | Grid-Tied Home Solar System (18kW-36kW PV) - Image 2

Product Summary:

This EG4 energy storage kit combines the FlexBOSS18 Hybrid Inverter with the 14.3kWh WallMount Indoor Battery to deliver a powerful, scalable solution for residential and commercial systems. The WallMount provides UL-certified LiFePO₄ storage, 8,000+ cycles at 80% DoD, self-heating, emergency stop capability, and RS485/CANBus integration for seamless communication.The FlexBOSS18 handles up to 18,000W PV input with dual MPPTs, 90A grid feed-through, and integration with the GridBOSS MID gateway for advanced load management, AC coupling, and generator support. Featuring rapid shutdown, ground and arc fault protection, and full remote monitoring, this kit ensures efficient, safe, and reliable energy performance for both grid-tied and off-grid applications.

EG4 Wallmount 280Ah Indoor Battery & FlexBoss18 Hybrid Inverter (ESS) | 14.3-57.2kWh | UL9540 | Grid-Tied Home Solar System (18kW-36kW PV)

$6,725.00

SKU# K0108

Battery Selected

1× EG4 280Ah Indoor

Total Capacity

14.3 kWh

Inverter Selected

1× EG4 FlexBOSS18

Input / Output

18 kW / 13 kW

Choose Your Inverter Option*

EG4 12kPV EG4 18kPV EG4 FlexBOSS18 EG4 FlexBOSS21 None

Choose Your Battery Option*

BigBattery ETHOS EG4 280Ah All Weather EG4 280Ah Indoor EG4 314Ah Indoor None

Choose Your Inverter Option*

EG4 6000XP EG4 12000XP VICTRON MP II 3000 VICTRON MP II 5000

Choose Your Battery Option*

BigBattery NEXUS BigBattery ETHOS BigBattery HUSKY2 INV EG4 280Ah All Weather EG4 280Ah Indoor

Choose Your ESS Configuration*

1x Inverter

Standard

2x Inverter

Large

SKU: K0108-V Category: UL Grid-Tied

Quantity:

Battery QTY

Inverter QTY

Clear

Compatible Accessories & Additional Add-ons

EG4 GridBOSS 200A MID

+ $1,798.11 ~~$2,399.95~~

Simple System Expansion
EG4 FlexBoss18 + Indoor ESS

EG4 FlexBoss18 + Indoor ESS
Power that never sleeps at night

See More On YouTube

Battery Downloads

SKU#:K0108

Spec Sheet:

Quick Start Guide:

UL9540A Certificate:

UL1973 Certificate:

Connection Guide:

Monitoring & Settings Guide:

DOWNLOAD

Maintenance Guide:

DOWNLOAD

Firmware Update Guide:

DOWNLOAD

CEC Listing- EG4 WallMount Indoor:

GO TO LINK

Battery Specifications

System Voltage:48V

Nominal Voltage:51.2V

Chemistry:LiFePO4

kWh Capacity:14.3kWh

Ah Capacity:280Ah

BMS Charging Voltage (Bulk/Absorb):56V (±0.8V)

Rec. Charging Voltage (Bulk/Absorb):56.2V (±0.2V)

Rec. Float Setting:54V (±0.2V)

Rec. SoC Cutoff Setting:20%

Max. Continuous Charge/Discharge Current:200A

Rec. Charge Current:60 – 160A

Rec. Discharge Current:160A

Max Continuous Discharge Rate:10240W

Voltage:56V

Power Consumption:224W

Internal Temperature Cutoffs:≤32ºF (On) | ≥41ºF (Off)

Charging Temperature Range:32ºF – 113ºF (0ºC – 45ºC)

Discharging Temperature Range:-4ºF – 122ºF (-20ºC – 50ºC)

Storage Temperature Range:-4ºF – 122ºF (-20ºC – 50ºC)

Protection Rating:IP20

Communications:RS485 | CANBus

Weight:282.2 lbs (128 kg)

Depth:9.6 in (245 mm)

Width:18.1 in (460 mm)

Height:36.4 in (925 mm)

Inverter Downloads

SKU#:K0108

Spec Sheet:

DOWNLOAD

User Manual:

DOWNLOAD

UL1741 Certificate:

DOWNLOAD

CEC Listing- EG4 FlexBoss18:

GO TO LINK

Inverter Specifications

Nominal AC Voltage:120/240VAC | 120/208VAC (L1/L2/N required)

Frequency:60 Hz (Default) | 50 Hz

Max. AC Current:54A @ 240V | 54A @ 208V

Max. AC Input Power:13000W

Max. AC Bypass:90A

Operating Voltage Range:180 – 270VAC

Output Voltage:120/240VAC | 120/208VAC (L1/L2/N required)

Max. Output Current:66.7A

Output Frequency:60 Hz (Default) | 50 Hz

Nominal Output Power (without PV):12000W @ 240V | 12000W @ 208V

Nominal Output Power (with PV):16000W @ 240V | 13800kW @ 208V

Power Factor:0.99 (Full Load)

Reactive Power Adjustment Range:-0.8 – 0.8 Leading Adjustable

Total Harmonic Distortion:<5% (Full Load)

Transfer Time:20ms (Default) | 10ms (Configurable) | 20ms (Parallel)

Rated Output Current:50A @ 240V | 57.7A @ 208V

Nominal Output Voltage:120/240VAC | 120/208VAC

Rated Output Power:12000W @ 240VAC | 12000W @ 208VAC

Peak Power:20000W (0.5 sec) | 15000W (1 sec)
12500W (6 min) | 11000W (12 min)

Operating Frequency:60 Hz (Default) | 50 Hz

Total Harmonic Distortion Voltage:<5%

No. of MPPTs:2

Inputs per MPPT:2 (MPPT 1) | 2 (MPPT 2)

Max. Usable Input Current:26A (MPPT 1) | 26A (MPPT 2)

Max. Short Circuit Input Current:31A (MPPT 1) | 31A (MPPT 2)

DC Input Voltage Range:100 – 600VDC

Unit Start-Up Voltage:200VDC

MPPT Operating Voltage Range:120 – 440VDC

Nominal MPPT Voltage:360VDC

Max. Utilized PV Array Power:1818000W

Max. Recommended PV Input:18000W

Max. Efficiency:97.5% (PV to Grid) | 94.5% (PV to Battery) | 94% (Battery to Grid)

Idle Consumption:<65W

Nominal Voltage:48VDC

Voltage Range:40 – 60VDC

Max. Charge / Discharge Power:10000W

Recommended Battery Capacity per Inverter:>300Ah

Operating / Storage Temperature Range:-13ºF – 140ºF (-25ºC – 60ºC)

Operating Altitude:<6,561 ft (2000 m)

Relative Humidity:0 – 100%

Typical Noise Emission:<50dB @ 3 ft

Design Topology:High-Frequency / Transformerless

Protection Rating:IP65 / NEMA 4X

Communications:RS485 / CANBus / WiFi / 4G

Max. Parallel Connections:10

Weight:115 lbs (52 kg)

Depth:11.2 in (287 mm)

Width:22.8 in (567 mm)

Height:30.5 in (775 mm)

Compare Battery & Inverter

FlexBoss18 Inverter: 10-Year EG4 Manufacturer Warranty
WallMount Indoor Battery: 10-Year EG4 Manufacturer Warranty