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
The ECO-WORTHY PowerMega 314 is the better 48V solar battery overall, rated 4.3 to 3.9. The ECO-WORTHY PowerMega 314 leads on value, output and features. The Fortress Power eVault MAX 18.5 wins on safety listing. The ECO-WORTHY PowerMega 314 costs $4,139.01 less ($2,339.99 vs $6,479).
Fortress Power eVault MAX 18.5
One of the largest single 48 V batteries sold, for whole-home or light-commercial systems installed by a dealer. Expect to pay dealer prices and plan for a heavy floor-standing cabinet.
Solamp $6,479$6,479
Prices were last checked October 24, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the ECO-WORTHY PowerMega 314 for value ($146 per rated kWh vs $352 per rated kWh), output (200 A continuous (about 10.2 kW) vs 180 A continuous (about 9.2 kW)) and features (app; no self-heating vs inverter communication; no self-heating).
- Choose the Fortress Power eVault MAX 18.5 for safety listing (UL 1973, UL 9540 listed vs UL 1973 listed).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every wall and floor mount 48V solar battery; a clear win is highlighted. How we rank explains each one.
| Factor weight | ECO-WORTHY PowerMega 314 | Fortress Power eVault MAX 18.5 |
|---|---|---|
| Overall rating | 4.3/5 | 3.9/5 |
| Value 35% | 100 $146 per rated kWh | 55 $352 per rated kWh |
| Output 15% | 48 200 A continuous (about 10.2 kW) | 29 180 A continuous (about 9.2 kW) |
| Warranty 15% | 100 10-year warranty | 100 10-year warranty |
| Safety listing 15% | 50 UL 1973 listed | 100 UL 1973, UL 9540 listed |
| Cycle life 10% | 100 10,000 cycles, maker rating | 100 8,000 cycles at 80% depth, maker rating |
| Features 10% | 50 app; no self-heating | 40 inverter communication; no self-heating |
Specifications
| ECO-WORTHY PowerMega 314 | Fortress Power eVault MAX 18.5 | |
|---|---|---|
| Capacity | ||
| Case | Wall or floor mount | Wall or floor mount |
| Nominal voltage | 51.2 V | 51.2 V |
| Capacity | 314 Ah | 360 Ah |
| Energy | 16.1 kWh | 18.4 kWh |
| Usable energy | 16.1 kWh | - |
| Chemistry | LiFePO4 | LiFePO4 |
| Cycle life | 10,000 | 8,000 at 80% depth |
| Power | ||
| Continuous discharge | 200 A | 180 A |
| Peak discharge | - | 250 A |
| Max charge current | 200 A | 180 A |
| Modules in parallel | Up to 15 | Up to 20 |
| Safety and communication | ||
| UL 1973 | Yes | Yes |
| UL 9540A | No | Yes |
| UL 9540 | No | Yes |
| Communication | CAN, RS485, RS232 | CAN, RS485 |
| Works with inverters | - | Fortress Envy, Fortress Solo |
| Self-heating | No | No |
| App | Yes | No |
| Build | ||
| Display | Yes | Yes |
| Built-in breaker | Yes | Yes |
| Enclosure | - | IP55 |
| Dimensions | 33.13 x 19.69 x 10.24 in | 20.3 x 20.3 x 42.2 in (515 x 515 x 1073 mm) |
| Weight | 280 lb | 520 lb |
| Warranty | 10 years | 10 years |
| Released | 2026-02 | 2021-06 |