EG4 WallMount 314Ah All-Weather Battery + FLEXBOSS21

$8,560.00

SKU# K0280-V

Introducing the WallMount 314Ah Batteries!

EG4 is proud to announce the next generation of our WallMount batteries with our 314Ah Indoor and All Weather versions! On top of the capacity improvements over our previous batteries, the WallMount 314Ahs have newly developed B

Choose Your Inverter Option*

APEX-6.5K APEX-10K EG4 6000XP EG4 12000XP None

Choose Your Battery Option*

APEX-6.5K APEX-10K EG4 6000XP EG4 12000XP None

Meet the EG4 WallMount 314Ah AllWeather Battery — a high-capacity, outdoor-ready energy storage unit built for installs where space, weather, and long runtimes all matter. Delivering 16kWh at 51.2V, it’s designed to be a dependable backbone for solar-plus-storage, off-grid power, or whole-home backup setups that need serious capacity with straightforward expandability.

At the core are lithium iron phosphate (LiFePO₄) cells paired with EG4’s smart BMS for stable performance and long service life, plus active cell balancing to help keep the pack operating efficiently over time. The enclosure is purpose-built for exterior placements with an IP67 rating, and internal heaters support reliable operation when temperatures drop. For day-to-day ownership and long-term maintenance, Bluetooth + Wi-Fi connectivity enables live status checks and over-the-air firmware updates through the EG4 app—so the system stays current without hassle.

Why it stands out

  • Big usable capacity: 16kWh (314Ah) for extended runtime and stronger backup coverage
  • True outdoor protection: IP67 enclosure built to handle dust, water, and harsh conditions
  • Smarter control: EG4 smart BMS with active cell balancing for better efficiency and longevity
  • Connected ownership: Bluetooth/Wi-Fi monitoring + OTA updates via the EG4 app
  • Cold-weather confidence: Built-in heaters for reliable performance in colder climates
  • Simplified scaling: Auto-addressing and closed-loop integration with EG4 inverters/batteries

Best-fit applications

A strong choice for residential and light commercial solar storage, outdoor battery banks, off-grid power systems, and backup power where durability, monitoring, and easy expansion are priorities.

Core specifications (at a glance)

Weight: 309 lbs

Nominal Voltage: 51.2V

Energy Capacity: 16kWh

Charge Capacity: 314Ah

Max Parallel (closed-loop): Up to 32 batteries

Certifications: UL 1973; UL 9540 with Flexboss21 & Flexboss18

Design Life: Tested 10,000+ cycles @ 80% DoD

Dimensions: 34.6″ × 21.7″ × 9.3″

https://youtu.be/piXdWAx8aus">https://youtu.be/piXdWAx8aus

 

Battery Downloads

SKU#:K0280, K0281, K0282, K0283, K0284, K0284, K0285
Spec Sheet:DownloadDOWNLOAD
User Manual:DownloadDOWNLOAD
Quick Start Guide:DownloadDOWNLOAD
UL9540 Certificate:DownloadDOWNLOAD
UL9540A Certificate:DownloadDOWNLOAD
UL1973 Certificate:PENDING
UN38.3 Certificate:PENDING

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 Downloads

SKU#:K0280, K0281, K0282, K0283, K0284, K0284, K0285
Spec Sheet:DownloadDOWNLOAD
User Manual:DownloadDOWNLOAD
UL1741 Certificate:DownloadDOWNLOAD
CEC Listing – BigBattery ETHOS + EG4 FlexBOSS21:Go to linkGO TO LINK

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)