FOSSiBOT F2400
#6 in LargeFull review
A low-cost 2kWh station for home backup and RV use when price per watt-hour matters more than charging speed.
Amazon $579 FOSSiBOT $609$579
The FOSSiBOT F2400 and the OUPES Mega 2 Pro are evenly matched, rated 4.2 and 4.1. The OUPES Mega 2 Pro wins on solar input and features. The FOSSiBOT F2400 costs $120 less ($579 vs $699).
OUPES Mega 2 Pro
#8 in LargeFull review
A 2kWh LiFePO4 station with an RV outlet and large expansion for home backup and RV owners on a budget.
OUPES $699$699
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 OUPES Mega 2 Pro for solar input (1,000 W max solar input vs 500 W max solar input) and features (UPS (20 ms), expandable, 140 W USB-C, app vs UPS (8 ms), 100 W USB-C, app).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every large portable power station; a clear win is highlighted. How we rank explains each one.
| Factor weight | FOSSiBOT F2400 | OUPES Mega 2 Pro |
|---|---|---|
| Overall rating | 4.2/5 | 4.1/5 |
| Value 25% | 100 $0.28 per rated Wh | 94 $0.34 per rated Wh |
| Tested capacity 15% | 64 84% of rated capacity delivered (2 tests) | 50 not yet independently tested (neutral score used) |
| Battery life 15% | 100 LiFePO4, 4,000 cycles, 5-year warranty | 100 LiFePO4, 4,000 cycles, 5-year warranty |
| AC output 15% | 54 2,400 W continuous AC | 58 2,500 W continuous AC |
| Charging speed 10% | 63 0-100% on AC in 2 h | 50 full AC charge time not published (neutral score used) |
| Portability 10% | 87 93 Wh per kg (48.5 lb (22 kg)) | 87 93 Wh per kg (48.8 lb (22.1 kg)) |
| Solar input 5% | 11 500 W max solar input | 40 1,000 W max solar input |
| Features 5% | 75 UPS (8 ms), 100 W USB-C, app | 100 UPS (20 ms), expandable, 140 W USB-C, app |
Independent capacity tests
FOSSiBOT F2400
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| techtest.org | 1,781 Wh | 87% | European 230V model, AC outlets at a 1,200W load (from the review’s capacity chart). Other AC runs: 1,717 Wh at 2,000W and 1,512 Wh at 100W. Full AC recharge took about 2 h 45 min at the 1,100W setting. |
| nextpit | 1,659 Wh | 81% | Full discharge of the European 230V model (load not stated); 2,127 Wh from the wall to recharge, about 78% round trip. |
OUPES Mega 2 Pro
No independent test published yet.
Specifications
| FOSSiBOT F2400 | OUPES Mega 2 Pro | |
|---|---|---|
| Battery | ||
| Rated capacity | 2,048 Wh | 2,048 Wh |
| Tested usable capacity | 1,720 Wh (84%) | - |
| Chemistry | LiFePO4 | LiFePO4 |
| Cycle life | 4,000 to 80%; US spec says 4000+, FOSSiBOT's global spec table says 3500 | 4,000 4000+ cycles to 80% |
| Expandable | No | Yes, up to 10,240 Wh |
| Output | ||
| AC output | 2,400 W (4,800 W surge) | 2,500 W |
| Boost mode (resistive loads) | - | 3,600 W |
| AC outlets | 6 total | 5 total |
| 120V 20A outlets (NEMA 5-20R) | 6 | 4 |
| RV 30A outlet (TT-30R) | - | 1 |
| AC waveform | Pure sine wave | - |
| USB-C ports | 4 (up to 100 W each) | 2 (up to 140 W each) |
| USB-A ports | 2 | 2 |
| 12 V car outlet | Yes | Yes |
| DC5521 ports | 2 | 0 |
| UPS / pass-through | Yes (8 ms switchover) | Yes (20 ms switchover) |
| Charging | ||
| AC charging | 1,100 W | 1,800 W |
| Full AC charge time | 2 h (Manufacturer: about 2 hours on AC; 1.5 hours with AC + solar (1600W)) | - |
| Max solar input | 500 W | 1,000 W |
| Solar input voltage | - | 12-80V (MPPT 18-80V, 30A) |
| Car charging | 100 W | 96 W |
| Build | ||
| Weight | 48.5 lb (22 kg) | 48.8 lb (22.1 kg) |
| Dimensions | 15.2 x 11.2 x 12.6 in | 18.8 x 11.6 x 11.6 in |
| App | FOSSiBOT app | OUPES app (Wi-Fi/Bluetooth) |
| Warranty | 5 years | 5 years |
| Released | 2022-11 | 2026-06 |