The OUPES Mega 5 is the largest unit in the Mega lineup, designed for heavy-duty home backup and professional-grade off-grid use. With a massive 5040Wh LiFePO₄ battery, 4000W continuous output, and expandable storage up to 15.12kWh, it delivers reliable long-duration power. This guide explores its performance, battery life, charging methods, and ideal users.
Product Overview Table
| Feature | Specification |
|---|---|
| Battery Capacity | 5040Wh |
| Inverter Power | 4000W (pure sine) / 8000W surge |
| Battery Type | LiFePO₄ (>3,500 cycles to 80%) |
| Weight | 116 lbs |
| Charging Methods | AC (1800W fast / 900W slow), Solar (1200W MPPT), Car, AC+Solar up to 3000W |
| Expandability | Up to 15.12kWh with 2× B5 batteries |
| UPS/EPS | <20 ms switchover |
| Ports | 6× AC outlets, 2× USB-C (100W PD), 4× USB-A, 2× DC5521, 1× Car port |
| Dimensions | 19.5 × 12.2 × 14.9 in |
| App Control | Wi-Fi + Bluetooth (OUPES App) |
| Protection | IP21, 5-year warranty (+1 year with registration) |
Performance
With 4000W continuous output and 8000W surge capacity, the Mega 5 can power nearly anything: large refrigerators, ovens, HVAC systems, and jobsite equipment. The <20 ms UPS function ensures seamless backup, keeping critical devices like servers or medical gear online.
Battery & Specs
- Base capacity: 5040Wh
- Expandable: Add two B5 batteries for a massive 15.12kWh storage
- Cycle life: >3,500 cycles to 80%
- BMS: Comprehensive protection against over-current, heat, and short circuits
This makes it a long-term backup solution with the durability of LiFePO₄ chemistry.
Portability & Design
At 116 lbs, the Mega 5 is best considered semi-portable. Its robust design includes large handles, and an optional roll cart is available for easier mobility. Despite its size, the footprint (19.5 × 12.2 × 14.9 in) is compact compared to other 5kWh-class stations. A large LCD and app connectivity simplify monitoring and control.
Charging Options
The Mega 5 supports high-speed recharging and hybrid input:
- AC (Fast Mode): 1800W (~3 hrs)
- AC (Slow Mode): 900W (~6 hrs)
- Solar: 1200W MPPT (12–150V), ~5 hrs in peak sun
- AC + Solar Hybrid: up to 3000W (~2 hrs)
- Car Input: slower charging for travel
Price & Value
The OUPES Mega 5 sits at the high end of the portable power market but provides exceptional storage and expandability. For those who want to replace small gas generators with a clean, quiet system, its long lifespan and modular growth potential add strong value.
Ideal Use Cases
- Whole-Home Backup: Runs large appliances and multiple devices for extended outages.
- Off-Grid Cabins: Provides reliable long-term power with solar expansion.
- Professional Job Sites: Supplies energy for heavy-duty tools and equipment.
- Emergency Preparedness: Expandable to 15.12kWh for days of backup without fuel.
Pros and Cons
Pros:
- 4000W continuous / 8000W surge output
- Huge 5040Wh base capacity
- Expandable up to 15.12kWh
- 3000W hybrid charging (AC+solar)
- App control for monitoring and settings
Cons:
- Heavy at 116 lbs (requires cart for easy movement)
- IP21 rating (indoor/covered use only)
- Higher upfront cost than smaller models
Final Verdict
The OUPES Mega 5 is built for households and professionals needing serious backup power. With 5040Wh of LiFePO₄ storage, 4000W output, and the ability to triple its capacity, it’s ideal for replacing gas generators or powering entire homes off-grid.
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FAQs
Can the OUPES Mega 5 power an entire house?
It can handle most household appliances but does not support 240V split-phase. For whole-home backup, pair it with transfer switches or specific circuits.
How expandable is it?
It supports up to two B5 batteries, increasing capacity to 15.12kWh.
How fast does it recharge?
With AC + solar, it can reach a full charge in ~2 hours under optimal conditions.
Is it portable?
At 116 lbs, it’s best treated as a stationary unit, though a roll cart is available for easier movement.
Last update on 2026-02-08 / Affiliate links / Images from Amazon Product Advertising API