This system pairs the EG4 WallMount All Weather battery with the EG4 FlexBOSS18 hybrid inverter to build a grid-tied home energy storage system (ESS). Usable capacity scales from 14.3kWh up to 85.8kWh depending on how many battery modules you add, and the inverter is rated to handle 18kW to 54kW of solar PV input. The system carries UL9540 certification, which is the safety standard for energy storage systems installed in and around homes.
Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
What This System Is
The EG4 WallMount All Weather battery is a lithium-based storage unit designed for outdoor and all-weather installation. It works alongside the EG4 FlexBOSS18, a hybrid inverter that manages solar input, battery charge/discharge, and grid interaction. Together they form a scalable ESS: you can size the battery bank from 14.3kWh to 85.8kWh of usable capacity, and the inverter accepts 18kW to 54kW of PV array input. The combination is intended for grid-tied home solar installations, not off-grid-only setups, though exact operating modes should be confirmed against the manufacturer documentation referenced below.
Battery Characteristics
Chemistry: LiFePO4 (Lithium Iron Phosphate) [NEEDS VERIFICATION — confirm cell chemistry against manufacturer documentation, as DATA does not explicitly state chemistry].
System voltage, group size, per-module capacity, cycle life, dimensions, weight, and terminal type are not included in the source data provided for this listing. These fields are flagged below as [NEEDS VERIFICATION] rather than estimated.
Wiring & Configuration Limits (Series/Parallel)
The 14.3kWh to 85.8kWh capacity range indicates this system supports parallel expansion of battery modules to reach higher usable capacity. The exact number of modules required per capacity tier, and any series/parallel wiring limits for the WallMount All Weather battery or FlexBOSS18 inverter, are [NEEDS VERIFICATION]. Do not assume series/parallel limits — confirm the maximum number of parallel battery units and inverter stacking limits against manufacturer documentation before ordering additional modules.
This system is NOT confirmed compatible with battery or inverter brands outside the EG4 WallMount All Weather and EG4 FlexBOSS18 product line. Do not mix battery ages, firmware versions, or chemistries within the same bank.
Pro-Installer Tip
Parallel battery banks are where most warranty claims start. If you add WallMount All Weather units to reach a higher kWh tier at different times, mismatched state-of-charge between old and new modules can cause the BMS in one unit to lock out while others keep cycling — that imbalance shortens the life of the whole bank. Before commissioning any expanded bank, bring every module to the same state of charge and verify balance with a shunt-based battery monitor, not just the inverter's dashboard estimate. As a professional standard, confirm the manufacturer's recommended depth of discharge (DoD) for this LiFePO4 [NEEDS VERIFICATION] chemistry before setting your inverter's cutoff — undercharging or over-discharging outside spec is a common cause of premature capacity loss in lithium ESS banks.
Key Benefits
- Scalable usable capacity from 14.3kWh to 85.8kWh to match household load growth
- Hybrid inverter accepts 18kW to 54kW of PV array input
- UL9540 certification for energy storage system safety
- All-weather rated battery enclosure for outdoor installation
Technical Table
| Spec | Value |
|---|---|
| Voltage | [NEEDS VERIFICATION] |
| Usable Capacity Range | 14.3kWh – 85.8kWh |
| Chemistry | [NEEDS VERIFICATION] |
| Inverter Model | EG4 FlexBOSS18 |
| PV Input Range | 18kW – 54kW |
| Certification | UL9540 |
| Max Continuous Discharge (A) | [NEEDS VERIFICATION] |
| Cycle Life | [NEEDS VERIFICATION] |
| Operating Temp Range | [NEEDS VERIFICATION] |
| Dimensions | [NEEDS VERIFICATION] |
| Weight | [NEEDS VERIFICATION] |
| Terminal Type | [NEEDS VERIFICATION] |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
This listing covers the EG4 WallMount All Weather battery paired with the EG4 FlexBOSS18 hybrid inverter, configured for grid-tied home solar. It is intended for use with compatible EG4 PV input ranging from 18kW to 54kW.
NOT confirmed compatible with third-party inverters or battery modules outside this listed system. NOT confirmed for off-grid-only operation without grid connection — this system is described as grid-tied. Standard lead-acid chargers are NOT applicable to this lithium-based system. Charging requirements, low-temperature charging protection, and BMS charge/discharge limits are [NEEDS VERIFICATION] — confirm against manufacturer documentation before installation, especially for cold-climate sites.
FAQ
What capacity range does this system cover?
Usable capacity scales from 14.3kWh to 85.8kWh depending on how many EG4 WallMount All Weather battery modules are added to the system.
What size solar array can this system handle?
The EG4 FlexBOSS18 hybrid inverter accepts a PV input range of 18kW to 54kW.
Is this system UL certified?
Yes. The system carries UL9540 certification, the safety standard for energy storage systems.
Is this an off-grid system?
No. This is listed as a grid-tied home solar system. Off-grid operating details are not confirmed in the manufacturer data provided; ask us before you order if off-grid operation is required.
Can I mix this battery with other brands or older modules?
No. Do not mix this system with third-party batteries or inverters. Mixing battery ages or chemistries within one bank is not recommended and can cause imbalance or BMS lockout.
Warranty & Support
Warranty terms for the EG4 WallMount All Weather battery and EG4 FlexBOSS18 inverter are not included in the data provided for this listing. Please refer to the "Resources (System Manuals and Warranty)" Tab above for full warranty terms. If you have questions about this system before ordering, ask us — we always reply back.
