ECO-WORTHY PowerMega 314
A low-cost 16 kWh floor battery for off-grid and backup builders who want big capacity with few modules. Permitted grid-tied installs may need a model with UL 9540A.
Amazon $2,499.99 ECO-WORTHY $2,339.99$2,339.99
4.2/5
A tough 5 kWh module for off-grid cabins, boats and small systems that need an outdoor-rated case. Larger inverters need three or more to run at full power.
- 5.4 kWhCapacity
- 60 AOutput
- 8,000Cycles
- YesUL 9540A
- 10 yearsWarranty
Check price at Current Connected$1,449
Price checked October 24, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- IP65 aluminum case can go outdoors or in a boat or RV bay
- Wall, floor or 19-inch rack mounting fits almost any space
- Talks to most major 48 V inverters, including Schneider, Victron and Sol-Ark
- Draws only about 2 W at idle, which matters off-grid
Cons
- Recommended continuous output is only 3 kW per module, so bigger inverters need several
- Heater is an extra kit
- Cannot be mixed with the original eFlex in one bank
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its case. How we rank explains each one.
Specifications
| Model number | eFlex MAX 5.4 |
|---|---|
| Capacity | |
| Case | Wall or floor mount |
| Nominal voltage | 51.2 V |
| Capacity | 105 Ah |
| Energy | 5.4 kWh |
| Chemistry | LiFePO4 |
| Cycle life | 8,000 at 80% depth |
| Power | |
| Continuous discharge | 60 A |
| Peak discharge | 130 A |
| Max charge current | 100 A |
| Modules in parallel | Up to 16 |
| Safety and communication | |
| UL 1973 | Yes |
| UL 9540A | Yes |
| UL 9540 | Yes |
| Communication | CAN, Modbus, Wi-Fi |
| Works with inverters | Fortress Envy, Schneider, Sol-Ark, Midnite Solar, OutBack, Morningstar, Phocos, Victron, Growatt |
| Self-heating | No |
| App | Yes |
| Build | |
| Display | No |
| Enclosure | IP65 |
| Dimensions | 17.5 x 7.2 x 24.2 in (446 x 184 x 616 mm) |
| Weight | 112 lb |
| Warranty | 10 years |
| Released | 2024-05 |
Alternatives in this case
Discover Helios ESS 16kWh
For homeowners who want a single large, heated, outdoor-rated battery that passes inspection. Its UL 9540 listing and direct inverter communication make it an easy choice for permitted grid-tied and off-grid builds.
NAZ Solar Electric $3,550$3,550
ECO-WORTHY Wallbank S100
An inexpensive wall-hung 5 kWh battery for indoor off-grid or backup systems. Pick the UL-listed Cubix100 if you need a permit.
ECO-WORTHY $869.99$869.99
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