Marbero M823
- AC delivered · est.
181 Wh. Show source
estimated sourcemarbero.com ↗2026-07-27- output
300 W. Show source
claimed sourcemarbero.com ↗- surge
375 W. Show source
claimed sourcemarbero.com ↗- weight
2.09 kg. Show source
claimed sourcemarbero.com ↗- recharge
360 min. Show source
claimed sourcemarbero.com ↗
Limited
#12 of 14
in the Ultraportable / carry class
Lifted by Portability and Output & versatility; held back by capacity & expansion.
Not enough tracked history for a verdict.
See alternatives to the Marbero M823 →At a glance
Marbero M823 is a ultraportable / carry model best suited to buyers matching its sourced output and capacity. It supplies 300 W of continuous AC output. Its current tracked price is $143.99; there is not enough tracked history for a verdict. BatteryRank scores it 26 out of 100 within its size class.
Capacity truth
The watt-hour number on the box isn't what reaches your devices. Rated on the label vs what actually leaves an outlet.
237 Wh. Show source
claimed sourcemarbero.com ↗2026-07-27The marketing number — total cell capacity.
181 Wh. Show source
estimated sourceestimate = battery-side usable capacity × 85% inverter efficiencyWhat reaches an AC outlet — about 15% is lost turning battery power into household AC. How we estimate.
What it can run
Same sourced device assumptions used by our calculators, applied to this model's usable AC energy. Actual runtime varies with load, temperature, and standby draw.
| Device | Estimated runtime | Sourced assumption |
|---|---|---|
| CPAP (humidifier off) | about 2.5 nights | 9 W · |
| CPAP (heated humidifier on) | about 0.4 nights | 56 W · |
| Refrigerator (full-size) | about 2.9 hours | 180 W × 35% duty cycle · |
| Wi-Fi router + modem | about 10 hours | 18 W · |
| Laptop (65W charger) | about 5.6 hours | 65 W × 50% duty cycle · |
| Phone (one full charge) | about 9 full charges | 20 W · |
How it scores
Four buyer pillars over seven sub-scores — computed from sourced data with a published formula, price-independent by design.
Power
est.Battery-side usable capacity and how much you can run at once.
Usable watt-hours and how far you can grow it with add-on batteries, versus its size class.
Continuous and surge wattage, outlet count, and USB-C fast-charging.
Trust
Owner reputation, safety record, warranty, and build durability.
Owner ratings, brand reputation, recall record, and warranty backing.
Rated cycle life, warranty length, cell chemistry, and weather sealing.
Charging
est.Wall and solar recharge speed.
Wall recharge speed, solar input, and multi-source charging.
Livability
62% dataLightweight, portable, and quiet enough to live with.
Weight, footprint, handle, and wheels, versus its size class.
Fan noise under load — quieter is better for bedrooms and CPAP use.
How this score is computed
The BatteryRank score is computed from sourced data with a published formula — ranked by data, not lab testing. Seven sub-scores blend into a 0–100 composite, grouped into four buyer pillars. Price is deliberately not a scoring input: prices move daily, so value intelligence lives in the price section above, judged against this model's own history.
| Pillar | Built from |
|---|---|
| Power | Capacity & expansion + Output & versatility |
| Trust | Trust & reliability + Durability & longevity |
| Charging | Charging & solar |
| Livability | Portability + Quiet / livability |
Scores are cohort-relative — each model is ranked against others in its size class. Missing inputs renormalize out rather than scoring zero (a model is never penalized for a spec nobody in its class publishes), and any figure resting on a documented estimate is tagged est. A full methodology page is coming.
Full specifications
Manufacturer-claimed unless marked verified (FCC/UL/DOE/lab). Tap or focus a figure to view its source.
Capacity & battery
- Battery chemistry
Lithium-ion. Show source
claimed sourcemarbero.com ↗- Rated capacity
237 Wh. Show source
claimed sourcemarbero.com ↗
The type of battery cell. LiFePO4 (LFP) cells last far more cycles and are more thermally stable than older lithium-ion (NMC) cells.
The battery's nameplate energy capacity — the headline number on the box. Battery-side usable and AC-delivered capacity are shown separately.
Power output
- Continuous power output
300 W. Show source
claimed sourcemarbero.com ↗- Surge power output
375 W. Show source
claimed sourcemarbero.com ↗- AC outlets
2 outlets. Show source
claimed sourcemarbero.com ↗- USB-A ports
4 ports. Show source
claimed sourcemarbero.com ↗- USB-C ports
1 ports. Show source
claimed sourcemarbero.com ↗- USB-C max output
18 W. Show source
claimed sourcemarbero.com ↗- DC barrel ports
1 ports. Show source
claimed sourcemarbero.com ↗
The most power you can draw at once, sustained — this has to be higher than the running wattage of whatever you're plugging in.
A brief power spike the unit can absorb when a device first switches on — matters for things with motors or compressors, like fridges.
How many standard wall-style outlets are built in.
How many USB-A ports are built in, for charging older phones, lights, and accessories.
How many USB-C ports are built in — check the per-port wattage below if you need fast charging for a laptop.
The fastest a single USB-C port can charge a device — relevant for laptops and fast-charging phones.
How many round barrel-style DC outputs are built in, used by routers, some lights, and older electronics.
Charging & solar
- AC charge time (0–100%)
360 min. Show source
claimed sourcemarbero.com ↗
How long a full recharge takes from a wall outlet, start to finish.
Size & portability
- Weight
2.09 kg. Show source
claimed sourcemarbero.com ↗
How much the unit weighs on its own, without accessories — relevant for portability and carrying it up stairs during an outage.
What else to consider instead of the Marbero M823
Same or adjacent size class, ordered by the price-independent composite. Every alternative is better than the Marbero M823 at something and worse at something else, so each row states both halves — each one arithmetic on two sourced readings, with a dimension skipped rather than guessed when either side is missing a figure.
- Goal Zero Yeti 300score 71 · same size class
- Why you would switch
- The Goal Zero Yeti 300 delivers 25% more usable AC energy (227 Wh vs 181 Wh).
- What you give up
- The Marbero M823 is $206 cheaper at the prices tracked on 2026-07-28 ($144 vs $350).
- EcoFlow RIVER 3 Plusscore 65 · same size class
- Why you would switch
- The EcoFlow RIVER 3 Plus delivers 34% more usable AC energy (243 Wh vs 181 Wh).
- What you give up
- The Marbero M823 is $155 cheaper at the prices tracked on 2026-07-28 ($144 vs $299).
- Bluetti Elite 30 V2score 63 · same size class
- Why you would switch
- The Bluetti Elite 30 V2 delivers 22% more usable AC energy (220 Wh vs 181 Wh).
- What you give up
- The Marbero M823 is $95 cheaper at the prices tracked on 2026-07-28 ($144 vs $239).
- Anker SOLIX C300score 62 · same size class
- Why you would switch
- The Anker SOLIX C300 delivers 49% more usable AC energy (269 Wh vs 181 Wh).
- What you give up
- The Marbero M823 is $156 cheaper at the prices tracked on 2026-07-28 ($144 vs $300).
- EcoFlow RIVER 3score 55 · same size class
- Why you would switch
- The EcoFlow RIVER 3 delivers 15% more usable AC energy (208 Wh vs 181 Wh).
- What you give up
- The Marbero M823 is $35 cheaper at the prices tracked on 2026-07-28 ($144 vs $179).
Quick answers
Each answer restates a sourced figure from elsewhere on this page — nothing new, nothing guessed.
- How much does the Marbero M823 weigh?
- 2.09 kg (4.6 lb), manufacturer-claimed, without accessories.
- What are the dimensions of the Marbero M823?
- 207 × 148 × 99 mm (8.1 × 5.8 × 3.9 in), length × width × height, manufacturer-claimed.
- How much capacity does the Marbero M823 deliver through an AC outlet?
- About 181 Wh of the rated 237 Wh reaches an AC outlet from a full charge — an estimate after our published 15% inverter-loss constant (marked est. on this page).
- How long does the Marbero M823 take to charge?
- 6 h from a wall outlet, 0 to 100%, manufacturer-claimed. Fast-charge modes and solar input differ — see the charging specs on this page.
- How many watts can the Marbero M823 output?
- 300 W continuous AC output and 375 W surge output, manufacturer-claimed. Appliance startup demand must stay within the relevant limit.