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EG4 280Ah All Weather + FLEXBOSS21 (ESS)

EG4 280Ah All Weather + FLEXBOSS21 (ESS)

Regular price $7,265.00 USD
Regular price $7,835.00 USD Sale price $7,265.00 USD
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California sales tax added at checkout. No sales tax charged on orders shipped outside California. Shipping calculated at checkout.
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EG4 Wallmount All Weather Battery & FlexBoss21 Hybrid Inverter (ESS) | 14.3-85.8kWh | UL9540 | Grid-Tied Home Solar System (21kW-63kW PV)

Product Summary:

The EG4 280Ah All-Weather Battery + EG4 FlexBOSS21 ESS System is a powerful, all-in-one energy solution designed for both on-grid and off-grid applications. Combining the rugged 14.3kWh EG4 All-Weather LiFePO₄ battery with the high-performance FlexBOSS21 hybrid inverter, this system delivers reliable, scalable, and intelligent energy management for residential and commercial use.

The FlexBOSS21 provides 12kW output and up to 21,000W PV input with 3 MPPTs, enabling maximum solar production and system flexibility. Paired with the durable All-Weather battery – featuring 8,000+ cycle life, integrated self-heating, and advanced safety protections – this system is built to perform in demanding environments.

Designed with UL 9540 certified configurations, advanced battery management, and U.S.-engineered components, this system ensures safe, maintenance-free performance with seamless closed-loop communication between battery and inverter.

Ships From: Texas, USA
Warranty: 10 Years (Battery), 10 Years (Inverter)
Support: Lifetime USA-Based Tech Support

Compatibility

Integrated & Optimized System:

  • EG4 280Ah All-Weather Battery + EG4 FlexBOSS21 Hybrid Inverter

Expandable & Flexible:

  • Add additional batteries for increased storage capacity
  • Supports grid-tied, hybrid, and off-grid installations
  • Compatible with solar + generator input configurations

Key Features

  • Complete ESS Solution – Battery + inverter system designed to work seamlessly together
  • 21,000W PV Input – High solar capacity with 3 MPPTs for maximum efficiency
  • 12kW Output Power – Supports residential and light commercial loads
  • 14.3kWh LiFePO₄ Battery – Durable, high-capacity energy storage
  • 8,000+ Cycle Life – Long-lasting performance at 80% DoD
  • All-Weather Design – Built for reliable operation in indoor and outdoor environments
  • Integrated Self-Heating – Reliable performance in cold climates
  • Advanced BMS & Safety Protections – Includes EMP protection, fire safety features, and system safeguards
  • Smart Energy Management – Supports load control, AC coupling, and generator integration
  • Remote Monitoring & Alerts – Real-time system tracking and control
  • Maintenance-Free Operation – No routine servicing required

A durable, high-performance energy storage system built for flexibility, resilience, and long-term energy independence.

Items Included- Quantity depends on Your ESS Configuration

EG4 WallMount 280Ah All Weather | 48V - 14.3kWh | UL1973 | Home Battery Backup LFPF
EG4 All Weather Conduit Box
EG4 FlexBOSS21 Hybrid Solar Inverter | 21kW PV / 16kW AC | Split-Phase | 4-MPPT | Scalable | Remote Wi-Fi Monitoring
Downloads & Specifications

Battery Specifications

Nominal Voltage:51.2V

Chemistry:Lithium Iron Phosphate (LiFePO4)

kWh Capacity:14.3kWh

Ah Capacity:280Ah

BMS Charging Voltage (Bulk/Absorb):56.0V (±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 Current:140A

Max. Continuous Discharge Current:140A (200A Max. Continuous for 30 min)

Rec. Charge Current:60 – 140A

Rec. Discharge Current:60 – 140A

Max Continuous Discharge Rate:10,240W

Voltage:56V

Power Consumption:224W

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

Charging Temperature Range:32ºF – 122ºF (0ºC – 50ºC)

Discharging Temperature Range:-4ºF – 131ºF (-20ºC – 55ºC)

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

Operating Altitude:<16,404 ft (<5,000 m)

Protection Rating:IP65

Communications:RS485 | CANBus

Weight:308.6 lbs (140 kg)

Depth:9.1 in (232 mm)

Width:22.3 in (566 mm)

Height:36.1 in (916 mm)

FlexBoss21 Hybrid Inverter (ESS)

Inverter Specifications

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

Frequency:60 Hz (Default) | 50 Hz

Max. AC Current:50A @ 240V | 57.7A @ 208V

Max. AC Input Power:12000W

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:24000W (0.5 sec) | 18000W (1 sec)
15000W (6 min) | 13200W (12 min)

Operating Frequency:60 Hz (Default) | 50 Hz

Total Harmonic Distortion Voltage:<5%

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

No. of MPPTs:3

Inputs per MPPT:2 (MPPT 1) | 2 (MPPT 2) | 1 (MPPT 3)

Max. Usable Input Current:26A (MPPT 1) | 26A (MPPT 2) | 15A (MPPT 3)

Max. Short Circuit Input Current:31A (MPPT 1) | 31A (MPPT 2) | 19A (MPPT 3)

DC Input Voltage Range:100 – 600VDC

Unit Start-Up Voltage:100VDC

MPPT Operating Voltage Range:120 – 440VDC

Nominal MPPT Voltage:360VDC

Max. Utilized PV Array Power:21000W

Max. Recommended PV Input:25000W

Max. Efficiency:97% (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:12000W

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

Max. Parallel Connections:16

Weight:88 lbs (40 kg)

Depth:11.3 in (287 mm)

Width:22.3 in (567 mm)

Height:30.5 in (775 mm)

Battery Downloads

SKU#:K0100
Spec Sheet:DownloadDOWNLOAD
User Manual:DownloadDOWNLOAD
UL9540A Certificate:DownloadDOWNLOAD
UL1973 Certificate:DownloadDOWNLOAD
Quick Start Guide:DownloadDOWNLOAD
CEC Listing- EG4 WallMount All Weather:Go to linkGO TO LINK

Inverter Downloads

SKU#:K0100
Spec Sheet:DownloadDOWNLOAD
User Manual:DownloadDOWNLOAD
UL1741 Certificate:DownloadDOWNLOAD
CEC Listing- EG4 FlexBoss21:Go to linkGO TO LINK

Waranty

EG4 FlexBoss21 Inverter: 10-Year EG4 Manufacturer Warranty

EG4 All Weather Battery: 10-Year EG4 Manufacturer Warranty



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