Product Description

The EG4 WallMount 280Ah All-Weather is a 48V-class (51.2V nominal) LiFePO4 battery that puts 14.3 kWh of home energy storage on the wall instead of the floor. Its IP65-rated enclosure is built for indoor or outdoor installation, it carries a UL1973 certification, and it communicates in closed-loop with EG4 and other compatible 48V inverters. OffGrid Horizon is a family-owned authorized EG4 dealer, and every unit ships with full manufacturer warranty support.

Who This Is For

This battery fits homeowners adding storage to a 48V inverter system where the practical mounting spot is an exterior wall, a garage, or a utility space. Because the enclosure is weather-rated, the battery can be installed beside an outdoor-mounted inverter without building a dedicated battery room. It also suits owners of non-EG4 systems: per EG4, the BMS supports closed-loop communication with EG4, Schneider, Sol-Ark, Victron, Growatt, Luxpower, and Deye inverters over RS485/CAN.

Key Features

  • 14.3 kWh from a single wall-mounted unit — 280Ah at 51.2V nominal
  • IP65 all-weather enclosure rated for indoor or outdoor installation
  • UL1973 certified, with UL9540A fire-safety test data — EG4 lists this model as "UL1973, UL9540A (Passed)"
  • Over 8,000 cycles at 80% depth of discharge per EG4, for up to 82.6 MWh of lifetime energy throughput
  • 140A continuous charge and discharge, with 200A discharge supported for 30 minutes per EG4's spec sheet
  • Integrated self-heating — a 224W internal heater activates at or below 32°F so the pack can accept charge in cold weather
  • LCD touchscreen for on-battery status monitoring
  • Closed-loop RS485/CAN communication with EG4 and other compatible inverters

Why EG4

EG4 Electronics is a Texas-based manufacturer that publishes full spec sheets, test data, and installation manuals for its equipment and backs this battery with a 10-year warranty. Its inverters and batteries are designed to work as one system, so state-of-charge reporting and charge control stay coordinated without third-party configuration work.

Specifications

Nominal voltage 51.2V (48V class)
Capacity 280Ah / 14.3 kWh
Chemistry LiFePO4 (lithium iron phosphate)
Cycle life Over 8,000 cycles at 80% DoD, per EG4
Max continuous charge 140A
Max continuous discharge 140A (200A for 30 minutes, per EG4)
Enclosure rating IP65 — indoor or outdoor installation
Charge temperature 32°F to 122°F
Discharge temperature -4°F to 131°F
Self-heating 224W internal heater, activates at or below 32°F per EG4
Dimensions 36.1 x 22.3 x 9.1 in
Weight 308.6 lb
Communication RS485 / CAN, closed-loop with compatible inverters
Certifications UL1973; UL9540A (Passed), per EG4
Warranty 10 years, per EG4
SKU FEWPP-48143-G1

All-Weather vs Indoor — Which WallMount?

EG4's WallMount line includes three residential models. This 280Ah All-Weather unit delivers 14.3 kWh in an IP65 enclosure. The newer WallMount 314Ah All-Weather steps up to 16 kWh with an IP67 enclosure and a 10,000-cycle rating per EG4. The WallMount 314Ah Indoor offers the same 16 kWh in a lighter IP20 enclosure for garages, basements, and utility rooms. All three include self-heating for cold-weather charging. If your project needs outdoor mounting, choose an All-Weather model; if the battery will live indoors and you want the lightest unit, the Indoor model is the practical pick.

Inverter Compatibility

The battery communicates in closed-loop over RS485/CAN with EG4 inverters, including the EG4 FlexBOSS18 hybrid inverter, so the inverter reads real state-of-charge directly from the BMS. Per EG4, closed-loop profiles are also available for Schneider, Sol-Ark, Victron, Growatt, Luxpower, and Deye inverters. Call us to confirm the correct protocol setting for your inverter before ordering.

Installation

Installation should be performed by a licensed electrician, and residential energy storage is subject to local permitting and inspection. At 308.6 lb, this battery requires mechanical lifting equipment or several people to position, and it must be anchored to structural framing capable of carrying the load. Follow the EG4 installation manual for mounting hardware, torque values, and required clearances, and site outdoor units out of direct afternoon sun where practical.

Warranty & Support

EG4 backs the WallMount 280Ah All-Weather with a 10-year manufacturer warranty. Register the battery with EG4 after purchase and keep your OffGrid Horizon invoice — as an authorized dealer, our sales records document your coverage. If you ever need warranty service, call us at (302) 496-3554 and we will help you work through EG4's process.

Shipping

This battery ships by LTL freight on a pallet within the United States. Delivery is curbside with a liftgate. Please inspect the packaging and unit before signing the delivery receipt, and note any damage with the driver — this preserves your ability to file a freight claim.

Frequently Asked Questions

Can this battery be mounted outdoors?

Yes. The IP65-rated enclosure is designed for indoor or outdoor installation. Keep it within EG4's published operating temperature ranges and out of standing water or direct spray where possible.

Will it charge in freezing weather?

The cells themselves charge from 32°F to 122°F, but the built-in 224W heater activates at or below 32°F per EG4, warming the pack so charging can resume in cold conditions. Discharge is supported from -4°F to 131°F.

Can I parallel multiple units?

Yes — the battery is designed to parallel with additional WallMount units to grow a bank. EG4 does not publish a maximum parallel count on this model's spec sheet, so call us to confirm the supported bank size for your inverter setup.

Which inverters work in closed-loop?

EG4 inverters such as the FlexBOSS series, plus Schneider, Sol-Ark, Victron, Growatt, Luxpower, and Deye models per EG4's published compatibility list.

What does the UL9540A reference mean?

UL9540A is a fire-safety test method, not a product listing. Per EG4, this battery has passed UL9540A testing, and it carries a UL1973 certification. Your local building department can confirm which documentation applies to your permit.

How long will it run my house?

14.3 kWh covers roughly half a day to a full day of essential loads (refrigeration, lighting, communications, a well pump used sparingly) for a typical US household. For whole-home or multi-day coverage, parallel additional units.

Not sure whether the 280Ah or 314Ah WallMount fits your system? Call OffGrid Horizon at (302) 496-3554 — we are a family-owned authorized EG4 dealer and will help you size the bank before you order.

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