Anker 20,000mAh (built-in cable) review

What it is and who it suits

The A1383 is a brick-shaped power bank with a 20,000 mAh cell and three ways to deliver power: a built-in USB-C cable, a USB-C port and a USB-A port. Anker's specification page lists it at about 6.2 by 2.9 by 1 inch (15.75 by 7.35 by 2.6 centimeters) and roughly 15 ounces (430.91 grams).

It suits a household that wants a charger ready for an outage in one place, such as a kitchen drawer, with a cable that cannot go missing. Ready.gov's outage advice is to plan for a portable charger or power bank. For lighter pocket options, see our power bank comparison.

What the 87W figure means

Anker lists the total output as 87W, made up of 65W and 22W. The built-in cable and the USB-C port can each deliver up to 65W, and the USB-A port up to 22.5W. That total is a ceiling shared across the ports, not a per-port rate.

Anker's user guide also lists lower limits when several ports are used at once, including 24W for the USB-C and USB-A ports combined at 5V. If you plan to run a laptop and a phone together, expect each to get less than its maximum.

How many charges a 20,000 mAh bank delivers

Anker explains that mAh measures charge, not energy. At a 3.7V cell voltage, a 20,000 mAh cell stores about 74 watt-hours, and the circuit converts that to 5V or higher with losses. Anker assumes roughly 80 to 85 percent efficiency in its example, so the usable energy is less than 74 watt-hours.

Anker's FAQ says that is why a 20,000 mAh bank charges a phone only a few times, and that the advertised capacity is not misleading. Treat it as a guide to energy, not a promise of a set number of charges.

Recharging, trickle mode and the built-in cable

You recharge the bank through the built-in cable or the USB-C port. A button press shows the battery level on the display. For earbuds and other low-power gadgets, the user guide says to double-click the button to start trickle-charging mode when using the USB-A port. The USB-C port and cable adjust on their own.

If the built-in cable seems dead, Anker suggests trying it on other devices and plugging both ends of the cable into the bank's own ports for 3 to 5 seconds. A built-in cable is convenient, but if it is damaged you cannot swap it, so keep a spare USB-C cable for the port.

Safety, storage and flying

Anker's safety guide gives an operating and storage range of 32°F to 95°F and says to avoid parked cars and direct sun. For long-term storage, it recommends about 60 percent charge, recharged every three months. It also says not to disassemble the bank, cover it while in use, charge it for long periods on beds or sofas, or store it with keys or other metal objects.

Anker says power banks below 27,027 mAh, or 100 watt-hours, can normally be taken on a flight and must go in carry-on luggage, not checked bags, and to confirm with your airline because rules change. At 20,000 mAh, this one is under that limit. Our power outage checklist covers where a power bank fits at home.

Who should skip it

Skip it if you only want a pocket-sized top-up, since about 15 ounces is a lot to carry every day. Also skip it if you need a bank to run a laptop and a phone at full speed together, or one that can power a small appliance. For that, look at a portable power station.

Is the Anker A1383 allowed on a plane?

Anker says power banks under 27,027 mAh, or 100 watt-hours, can normally be taken on a flight, and that they belong in carry-on luggage, not checked bags. This one has a 20,000 mAh cell, so it falls under that limit, but check with your airline before you fly.

Can it charge a laptop?

Anker lists up to 65W from the built-in cable or the USB-C port, which suits many USB-C laptops. Output is shared, with 87W the total for all ports, so run the laptop alone for best speed. Check your laptop's charger rating before relying on it.

How should I store it between uses?

Anker's safety guide says to keep it between 32°F and 95°F, out of direct sun and parked cars, at about 60 percent charge. It says to top it up every three months, and keep it away from keys and other metal objects.

What if the built-in cable stops working?

Anker suggests testing the cable on other devices and plugging its two ends into the bank's own ports for 3 to 5 seconds. The USB-C and USB-A ports still work for charging devices, and the USB-C port can recharge the bank, so keep a spare cable.