The EG4 314Ah All-Weather Battery + EG4 FlexBOSS21 ESS System delivers maximum capacity, rugged durability, and advanced hybrid power control for both on-grid and off-grid applications. Combining the 16kWh EG4 WallMount All-Weather LiFePO? battery with the high-performance FlexBOSS21 hybrid inverter, this system provides scalable, reliable energy for residential and light commercial installations.
The FlexBOSS21 delivers 16kW output and up to 21,000W PV input with 3 MPPTs, maximizing solar production and system flexibility. Paired with the EG4 314Ah All-Weather battery – featuring 200A continuous output,8,000+ cycle life, and a smart BMS with active cell balancing – this system ensures stable, efficient energy delivery over the long term.
Designed withUL 9540 certified configurations, advanced battery management, andU.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
CompatibilityIntegrated & Optimized System - EG4 314Ah All-Weather Battery + EG4 FlexBOSS21 Hybrid Inverter
Expandable & Flexible - Cross-compatible with other EG4 battery systems
- Scalable energy storage for growing system needs
- Supports grid-tied, hybrid, and off-grid installations
- Key Features
- Complete ESS Solution – Battery + inverter system designed to work seamlessly together
- 21,000W PV Input / 12kW Output – High-capacity power for residential and commercial systems
- 3 MPPT Inputs – Maximizes solar production across multiple arrays
- 16kWh LiFePO? Battery (314Ah) – High-capacity, durable energy storage
- 200A Continuous Output (~9.6kW) – Supports whole-home and critical loads
- IP67 Outdoor-Rated Design – Built to withstand dust, water, and harsh environments
- 8,000+ Cycle Life – Long-lasting performance at 80% DoD
- Advanced Smart BMS – Active cell balancing for improved efficiency and lifespan
- Self-Heating Function – Reliable operation in cold climates
- Bluetooth & Wi-Fi Monitoring – Real-time tracking and OTA firmware updates
- Closed-Loop Communication – Seamless coordination between battery and inverter
- GridBOSS Integration – Advanced load management, AC coupling, and generator support
- Maintenance-Free Operation – No routine servicing required
A high-capacity, outdoor-ready energy storage system built for durability, intelligent control, and long-term energy independence.Battery Specifications - Product Type: LFP Battery
- Battery Type: Lithium Iron Phosphate (LFP)
- Model Number: WM48314AWXX (XX is a number between 00 – 99)
- Nominal Energy Capacity: 16kWh
- Usable Energy (DOD%): 12.86kWh (80% recommended)
- Voltage Range: 47.5 – 57.6 VDC
- Nominal Voltage: 51.2 VDC
- Capacity: 314Ah
- Charging Voltage Range: 56 – 57 VDC
- Discharging Cut-off Voltage: 47.5 VDC
- Max Continuous Charge Current: 157A
- Max Continuous Discharge Current: 200A
- Continuous Charge/Discharge Power: 8/10.2 kW
- Recommended Charging/Discharging Rate: 0.5C
- Peak Power: 12.8kW (3 sec)
- Round-trip Efficiency: 95%
- Max Parallel Units: 32
- Protection Features: Over/Under Voltage, Over-Current, Short Circuit, High/Low Temp
- Battery Management System (BMS): Integrated, Active Balancing
- Communication Protocols: RS485, CAN
- Battery Breaker: 250A
- Storage Temperature Range**: -4 – 131°F (-20 – 55°C)
- Humidity Range: 5% – 95% RH (non-condensing)
- Altitude: 9843 ft. (<3000 m)
- Cooling Method: Natural Convection
- Dimensions (H × W × D): 34.6 in. × 21.7 in. × 9.3 in. (880 mm × 550 mm × 235 mm)
- Operating Temperature Range: Charge: 32 – 122°F (0 – 50°C); Discharging: -4 – 131°F (-20 – 55°C)
- Recommended DOD Setting Note*: EG4 recommends this value be set no lower than 20% to maintain the recommended 80% Depth of Discharge.
- Storage Temperature Note**: Less than 3 months of storage. If longer than 3 months, recommended storage temperature will be 59°F – 86°F (15°C – 30°C).
- Weight: 309 lbs. (140 kg)
- Enclosure Rating: IP67
- Mounting Options: Wall attatched/Floor mount
- Display/Indicators: LED Status
- Connector Type: Degson quick connector/screw terminal
- UL 1973: Pending
- UL 9540: Pending
- UL 9540A: Pending
- UN 38.3: Pending
- Cycle Life (70% EOL Capacity): 10000 cycles @ 0.5C, 25°C, 80% DOD
- Design Life*: 15 years
- Warranty: 10 years or 10000 cycles
- Application Type: Residential/Commercial/Off-grid/Backup
- Lifetime Energy Throughput: 122.2MWh
- Note: Information subject to change without notice.
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 DownloadsInverter Downloads