eFlex MAX 5.4kWh
Reliable Power - Rain or Shine
eFlex MAX 5.4kWh
Discover the power and flexibility of the eFlex MAX 5.4 LFP Battery, designed to provide you uninterrupted power in the most demanding environments and weather conditions. This top-tier lithium battery combines advanced technology with practical design to meet a wide range of energy needs while ensuring utmost safety and reliability.
8000 cycles guaranteed, 10-year warranty and the highest quality standard, make it perfect for both your home, apartment and condos, off grid cabins, RVs, boats and more.
Key Features
Robust Design with Salt Water-resistant Aluminum Enclosure – designed for both indoor and outdoor use without extra protective structures.
Longest Battery Life Span (8000+ cycles; 10+ year) – The patented 3/4″ aluminum enclosure design regulates the battery’s internal temperature high-power applications, resulting in 3 times greater thermal performance than competitors and extended life span.
99% Efficiency with 2W Idle Power – Enhanced Performance in Off-Grid Systems with 2W consumption, minimizing power loss in standby mode and resulting in cost savings.
Easy to Scale-up Battery Capacity to Match Your Energy Need – included Busbars enable faster installation of multiple units in parallel with fewer errors, handle higher power current than battery cables.
Clean, Streamlined and flexible Installation The waterproof front battery cover eliminates the extra wire management (such as conduits). Both Wall mount and floor mount are available.
Best Bang for Your Buck – Obtain lowest energy cost with best battery technology and product quality, highest performance and affordable price point.
Monitor and control your eFlex MAX Anywhere and Anytime!
✅ Monitor Performance of Each Battery
✅ Update Firmware Over The Air
✅ Participate in Virtual Power Plant Programs
Easy to Pair with Your Favorite Inverters with a simple click
Video Library
Make your home your Fortress with Uninterrupted Clean Power
Solar Energy, Grid Energy, Battery Storage, Generators and More.
Seamlessly integrating with our Fortress Power Envy Inverters, the eFlex MAX 5.4 kWh batteries enhance your system’s performance. Perfect for both home and business. Whether you’re seeking to reduce your environmental impact, energy costs, or rely on a steady power supply during outages, the eFlex MAX is your go-to solution. Make the smart switch to a greener, more efficient energy system today with our innovative battery technology.
For firmware updates and details about firmware releases, please visit our Firmware Support Page
| General | |
| Name | eFlex MAX 5.4 |
| Total Energy(kWh) | 5.4 |
| Max. Charge Current (Continuous) [A] | 100 |
| Max. Discharge Current (Continuous) [A] | 100 |
| Nominal Capacity [Ah] | 105 |
| Voltage Range [V] | 48-55 |
| Charging Temperature [F] | 32 ~ 114 |
| Discharging Temperature [F] | -4 ~ 131 |
| Storage Temperature [F] | 20 ~ 95 |
| Dimension [L x W x H, inch] | 17.5 x 24.2 x 7.2 |
| Weight [lbs] | 108 |
| Life Cycles | 8000 @ 80% DoD |
| Round Trip Efficiency | >98% |
| Part | Description | Qty |
| 1 | eFlex MAX 5.4kWh | 1 |
| 2 | 1¼ -Inch Threaded Conduit Fitting | 1 |
| 3 | Busbar Top Cover | 1 |
| 4 | Top eFlex MAX Cover | 1 |
| 5 | Wall Mount Bracket | 1 Pair |
| 6 | Manual | 1 |
| 7 | Busbar (300A) | 1 Pair |
| 8 | Busbar Bottom Cover | 1 |
| 9 | Wall Mount template | 1 |
| 10 | Floor Mount Bracket | 1 Pair |
| 11 | Back Support | 1 |
| 12 | 2-Way RJ45 Splitter | 1 |
| 13 | ENVY & Sol-Ark Battery-Inverter COMM Cable (2 ft.) | 2 |
| 14 | IP65 Battery-Inverter Comm Cable (9.8ft.) | 1 |
| 15 | IP65 Battery-Battery Comm Cable (1.15ft.) | 1 |
| A | M4 * 8 Stainless Steel Cross Recessed Countersunk Head Screw | 2 |
| B | M4 * 6 Stainless Steel Cross Pan Head Screw | 5+1 |
| C | M8 * 16 Combination Cross Groove Recessed Hexagonal Head Bolt | 4 |
| D | M4*25 Hexagonal Socket Head Cap Screw | 3 |
| E | M6 * 20 European Standard 30, T-bolt & M6 Flange Nut | 6+1extra |
| f | M8*60 Expansion Screw | 4 |
| G | M6*50 Wood Screw | 4 |
Related Products
The Fortress Power eFlex MAX 5.4kWh Battery plays nicely with the following products
Envy True 12 Inverter
True 12kW Whole Home Solar Storage Inverter
Envy 8k / 10k Inverter
8k / 10k Whole Home Solar Storage Inverters
Guardian Monitor
Monitor and Control your Fortress Power System Remotely