Buy the Anker SOLIX C300 if you want a 9.1 lb unit for a night or two of CPAP without the humidifier, laptop work away from outlets, or a small UPS for a router, with three 140 W USB-C ports. Skip it if you need to run anything over 300 W or anything with a motor that starts hard, such as a household fridge, kettle or hair dryer; it can't. It holds 288 Wh of LiFePO4, supplies 300 W through 3 AC outlets and lists a 10 ms UPS switchover.
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Anker SOLIX C300
Laptop work and phone charging on the go, with a 140W two-way USB-C port and 3 AC outlets.
- Capacity
- 288 Wh
- Output
- 300 W
- Weight
- 9.1 lb
- UPS
- 10 ms
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Check price on AmazonQuick verdict
- Good fit
- CPAP travel with the humidifier off; laptops and phones; a router on UPS; a 12 V camping fridge overnight
- Poor fit
- Household fridges; kettles, hair dryers, microwaves; a full outage day
- Weight
- 9.1 lb
- Grow later?
- No expansion battery
- Watch out for
- SurgePad (600 W) is a heater mode, not surge for motors
Key specs
From Anker's US product page. Starred values aren't confirmed on the spec sheet yet.
| Spec | Anker SOLIX C300 |
|---|---|
| Capacity | 288 Wh |
| Continuous output | 300 W |
| Surge | Not published |
| Boost mode (heating loads) | 600 W |
| Battery | LiFePO4, 3,000 cycles to 80% |
| Weight | 9.1 lb |
| AC outlets | 3* |
| USB-C | 3 × up to 140 W |
| 12 V car outlet | Yes |
| Wall charge, 0–100% | Not published |
| Solar input | 100 W, 11-28V, 8.2A (XT60) |
| UPS switchover | ≤10 ms |
| Extra batteries | Not expandable |
| Warranty | 5 years |
* Not stated on the maker's spec sheet, or derived from other official figures.
What will it run, and for how long?
Each device on its own from a full charge, running nonstop (the 12 V fridge cycles as normal). Divide CPAP hours by your hours of sleep to get nights. Includes the battery reserve, conversion losses and standby draw from our published formula.
| Device | Plugged into | Runtime or limit |
|---|---|---|
| CPAP, humidifier off11 W | 12 V outlet | 18–22 h |
| CPAP with heated humidifier and tube45 W | AC outlet | 3.5–4.3 h |
| 12 V portable fridge (45 L)about 0.3 kWh a day | 12 V outlet | 15–18 h |
| Laptop60 W | USB-C | 3.3–4.1 h |
| Wi-Fi router and modem15 W | AC outlet | 8–9.8 h |
| Starlink Mini30 W | AC outlet | 4.9–6 h |
| Electric blanket (queen)110 W, cycles on and off | AC outlet | 2.9–3.6 h |
| Top-freezer fridgeabout 0.99 kWh a day, 1,200 W to start | AC outlet | Won't run: needs about 1,200 W to start, and no surge rating is published |
| Electric kettle1,500 W | AC outlet | Won't run: needs 1,650 W with a safety margin; it supplies 300 W |
Add your own mix in the runtime calculator.
Where the C300 wins, and where it's ruled out
We ran eight common situations through the quiz engine. Rank is among every model that passes the hard limits.
| Situation | Result | Runtime or reason |
|---|---|---|
| Outage overnight: fridge, Wi-Fi and phones (carry it) | Ruled out | No published surge rating, and your start-up load (about 1,215 W) exceeds its continuous output. |
| Outage for a full day, same devices (wheels OK) | Ruled out | No published surge rating, and your start-up load (about 1,235 W) exceeds its continuous output. |
| CPAP for two nights away, one-hand carry | Ruled out | Runs your devices for about 17 h; you asked for 24 h. |
| Weekend car camping: 12 V fridge, lights, phones, with solar | Ruled out | Runs your devices for about 7.9 h; you asked for 24 h. |
| RV day: fan, TV, laptop, phones | Ruled out | Runs your devices for about 4.5 h; you asked for 24 h. |
| Remote work day: Starlink, laptop, phone | Ruled out | Runs your devices for about 2.1 h; you asked for 24 h. |
| Home office on UPS: router, laptop, phone, overnight | Ruled out | Runs your devices for about 4.6 h; you asked for 10 h. |
| Overnight essentials on a budget under $500 | Ruled out | No published surge rating, and your start-up load (about 1,215 W) exceeds its continuous output. |
Every one of those eight situations asks for more than 288 Wh or 300 W: a household fridge it can't start, or a full day of devices it can't cover. That's expected for this size. The situations below are the ones a 300 Wh unit is built for.
Where a 300 Wh unit fits
Smaller loads, run through the same engine across the whole catalog. The C300 is a top pick for one night of CPAP without the humidifier and for an overnight 12 V camping fridge; the other rows show where you need a bigger unit. Open any row in the quiz and change the devices.
CPAP for one night, humidifier off, plus a phone
0.1 kWh/day · 10 h · one-hand carry
Open this in the quiz and change the devices
Engine's pick
EcoFlow RIVER 3 Plus
About 11 h · also Anker SOLIX C300, Bluetti Elite 30 V2
Same night, heated humidifier and tube on
0.4 kWh/day · 10 h
Open this in the quiz and change the devices
Engine's pick
Anker SOLIX C1000 Gen 2
About 16 h · also Anker SOLIX C800X / C800 Plus, EcoFlow RIVER 2 Pro
Overnight car camping: 12 V fridge and two phones
0.4 kWh/day · 10 h
Open this in the quiz and change the devices
Engine's pick
Jackery Explorer 300
About 14 h · also Anker SOLIX C300 DC, Anker SOLIX C300
Overnight outage: Wi-Fi router and two phones
0.4 kWh/day · 10 h
Open this in the quiz and change the devicesJackery512 WhEngine's pick
Jackery Explorer 500 v2
About 14 h · also Anker SOLIX C800X / C800 Plus, Anker SOLIX C1000 Gen 2
A full workday away from outlets: laptop and phone
0.3 kWh/day · 24 h
Open this in the quiz and change the devicesJackery512 WhEngine's pick
Jackery Explorer 500 v2
About 38 h · also Anker SOLIX C800X / C800 Plus, EcoFlow RIVER 3 Max
Picks come from the same engine as the quiz, recalculated whenever our catalog changes.
What does it do well?
- CPAP travel. With the humidifier off, about 21 h of CPAP on the 12 V outlet, about 2.6 nights of 8 hours, in a 9.1 lb unit.
- Laptop work. 3 USB-C ports at up to 140 W; a typical laptop runs about 3.9 h straight from USB-C, skipping the inverter.
- A small UPS. A listed switchover within 10 ms keeps a router or CPAP running through a blink.
- Charges several ways. Up to 330 W from the wall (0–80% in 50 minutes), through the two-way USB-C port, or up to 100 W of solar at 11-28V, 8.2A (XT60).
- Battery and warranty. LiFePO4 rated for 3,000 cycles to 80%, and a 5-year warranty.
What should you know before you buy?
- 300 W is the hard limit. No surge rating is published, so household fridges, sump pumps and other motor loads are out. SurgePad lets a heating appliance run at reduced power; it isn't extra output.
- A heated humidifier cuts CPAP time hard. About 4.1 h with the humidifier and heated tube on. Use the CPAP maker's approved DC cable, turn off the unit's ECO or auto-off setting so it doesn't cut the AC outlets at a low load, and talk to your doctor and your utility's medical program before relying on any battery.
- The outlet listing has an error. Anker labels the outlets "NEMA 6-20", a 240 V plug; we treat that as a page error for standard 120 V outlets, but check the photos before you buy.
- Check the box contents. One reseller shows the Amazon listing as a C300 plus 60 W solar panel bundle, so confirm what's included.
- No expansion. 288 Wh is all you get; for a full outage day with a fridge, look at a 1 kWh unit.
What are the closest alternatives?
The Jackery Explorer 300 is the lighter option at 7.5 lb with 292 Wh and 300 W, but no published UPS switchover and a single 100 W USB-C port; see Explorer 300 vs C300 and our Explorer 300 guide. The Bluetti Elite 30 V2 holds 288 Wh with 600 W continuous, double the C300's, and a 10 ms switchover at 9.48 lb. For more small options, see the best small power stations.
Jackery Explorer 300
292 Wh and 300 W at 7.5 lb; no published UPS switchover.
- Capacity
- 292 Wh
- Output
- 300 W
- Weight
- 7.5 lb
- UPS
- None
Paid link
Check price on Amazon
Bluetti Elite 30 V2
288 Wh with 600 W continuous and a 10 ms UPS switchover.
- Capacity
- 288 Wh
- Output
- 600 W
- Weight
- 9.5 lb
- UPS
- 10 ms
Paid link
Check price on AmazonWho should buy it, and who shouldn't?
- Buy it for CPAP trips with the humidifier off, for laptop and phone charging on the go, for a 12 V cooler on an overnight trip, or as a small UPS for a router.
- Skip it if you need to run a household fridge, kettle, hair dryer or microwave, a heated CPAP humidifier all night, or a full day of outage backup. The sizing quiz checks your devices against every model.
Related: how long a power station runs an electric blanket, camping picks, or every model in the comparison chart.
What people actually ask
How many nights of CPAP will the Anker C300 run?
With the humidifier off, about 2.6 nights of 8 hours on the CPAP's 12 V DC cable, or about 1.3 nights through the AC outlet and power brick. With a heated humidifier and tube it's about 4.1 h, less than one night. This is power planning, not medical advice: use your CPAP maker's approved DC cable, check its power specs, talk to your doctor, and register with your utility's medical program, which gives notice of outages but doesn't guarantee power.
Can the Anker C300 run a refrigerator?
No. A household fridge needs about 1,200 W to start, and the C300 supplies 300 W with no published surge rating. SurgePad's 600 W is for heating appliances only. A 12 V compressor fridge on the car outlet is a different story: about 17 h for a typical 45 L model.
Does the C300 work as a UPS?
Anker lists a switchover within 10 ms, enough for a router, modem or CPAP to keep running when the power blinks. With 288 Wh, a router and modem alone last about 9.4 h. Turn off any ECO or auto-off setting so the AC outlets don't shut off at a low load.
Can I charge the C300 over USB-C?
Yes. One of the USB-C ports works both ways at up to 140 W, so a laptop charger can refill it. From the wall it charges at up to 330 W, 0–80% in 50 minutes, and it takes up to 100 W of solar through its XT60 input.
What's the difference between the C300 and the C300 DC?
The C300 DC drops the AC outlets entirely and is lighter. If everything you power runs on USB-C or a 12 V car plug, it's worth a look; if you need even one wall plug, get the C300.
The bottom line
The C300 is a 9.1 lb, 288 Wh unit for small, steady loads: about 2.6 nights of CPAP without the humidifier, laptops on 140 W USB-C, and a router on UPS. It can't start a fridge or run anything over 300 W, so for outage backup with a fridge, step up to 1 kWh.
Anker SOLIX C300
Laptop work and phone charging on the go, with a 140W two-way USB-C port and 3 AC outlets.
- Capacity
- 288 Wh
- Output
- 300 W
- Weight
- 9.1 lb
- UPS
- 10 ms
Paid link
Check price on Amazon