Anker SOLIX C300
Specs checked
Our take
A small box for small things. It keeps Wi-Fi and phones going for about 7.0 hours. It is not for a fridge.
- 288 Wh
- Watt-hours: how much it holds
- 300 W
- Watts: how fast it gives power
- Checking
- Surge: a short burst for start-ups
- 9.1 lb
- Weight: how heavy to carry
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How long it runs your things
Refrigerator
2.0 h
Wi-Fi router
16 h
Phones
12 h
Lights
6.1 h
CPAP machine
6.1 h
TV
2.4 h
Laptop
3.8 h
Fan
4.9 h
Estimates. Your devices may use more or less. One thing at a time, from a full box. We keep 85% of the watt-hours, because some power is lost on the way out.
What we think
The SOLIX C300 is a small box. It holds 288 watt-hours. Watt-hours are how much power a box holds. It gives up to 300 watts. Watts are how fast something uses power.
What that means in an outage
This is a box for small things, not for a fridge. By our math, counting Wi-Fi at 15 watts and phones at 20:
- Wi-Fi and phones: about 7.0 hours.
- A laptop that uses 65 watts: about 3.8 hours.
- CPAP: about 6.1 hours, by our math, for a CPAP that uses about 40 watts with the humidifier off or low. Check the watts on your own machine. That may not cover a full night.
These are estimates. Your devices may use more or less.
Why not a fridge
A fridge can need a surge of about 1,200 watts. Surge is a short burst some things need to start. Anker's page shows "600W", but its manual says that number is a mode called SurgePad, which works with heating devices. That is not surge. So the surge line says We're checking, and by our math this box does not start a fridge.
Why this one and not the EcoFlow RIVER 3 Plus
Both hold about the same: 288 watt-hours here, 286 there. This box weighs 9.1 pounds; the RIVER 3 Plus weighs 10.4. Its USB-C port gives up to 140 watts for a laptop; the EcoFlow's gives 100. Pick the EcoFlow if you want more watts. It gives 600 watts; this box gives 300.
Moving it and charging it
9.1 pounds is a little more than a gallon of water. Anker says it charges to 80% in 50 minutes from a wall outlet.
The limit
300 watts is the ceiling. That rules out a fridge, a microwave and a space heater. Anker lists no extra battery for it.
Bottom line: a light box that keeps you online and your phones full for one evening.
Good for
Keeping Wi-Fi, phones and a laptop on in a short outage. At 9.1 lb it is easy to carry.
Not for
A fridge, a microwave or a space heater. By our math this box does not start a fridge.
The numbers
Every number comes from the maker’s own page. If we could not confirm one, it says “We’re checking”.
| Watt-hours (how much it holds) | 288 Wh |
|---|---|
| Watts (how fast it gives power) | 300 W |
| Surge (short burst for start-ups) | We're checking |
| Weight | 9.1 lb |
| Battery type | LiFePO4 |
| Battery life | 3,000+ cycles to 80% capacity |
| Time to charge from the wall | 80% in 50 minutes from a wall outlet |
| Most solar it can take | 100 W |
| Wall-style outlets | 3 |
| Fastest USB-C port | 140 W |
| Switch-over time in an outage | 10 ms |
| Can you add batteries? | No. Anker lists no expansion battery for it. |
| Warranty | 5 years |
| Size | 6.5 x 6.3 x 9.5 in |
Specs last checked on October 5, 2026. See the maker’s page →
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