Anker Nano Power Bank A1638 Review (2026): No Cable Needed

This Anker Nano Power Bank (10K, 45W, Built-In Retractable USB-C Cable) A1638 review looks at a power bank built around one idea: you should never have to dig for a charging cable. The cable lives inside the body and pulls out when you need it. It is aimed at commuters and travelers who want fast phone charging without carrying extra cords. This review is based on Anker's published specifications and what independent expert reviews report, not on our own hands-on testing.

Design and build: the cable is the headline

The built-in retractable USB-C cable stretches to 2.3 ft. The cable retracts into the body when you are done. Anker rates it for over 20,000 bends.

The bank measures 3.21 × 1.99 × 1.42 in and weighs 0.51 lb. It holds 10,000mAh, a capacity that suits phones and tablets. A common criticism from reviewers is that the body is thick and chunky, so it is less pocketable than slimmer 10K banks. If you carry it in a bag, that matters little. If you want something flat for a jeans pocket, check the depth first.

The cable is also the main design risk. Because it is integrated, a failure would cost you a key function of the product, as reviewers point out. A conventional bank with a separate cable lets you swap in a new cord. The listing shows a 24-month warranty on US retail listings.

Features and what they mean day to day

Smart display

The display shows battery percentage, wattage, battery health and temperature. Reviewers praise it. A percentage readout is useful on any power bank, and live wattage shows whether your phone is drawing a fast charge. The temperature reading matters here too, because heat affects this bank's output (more on that below).

Pass-through charging

Pass-through charging lets you recharge the bank while it charges a device. This helps if you only have one wall outlet at a hotel desk or airport gate. You plug the bank into the wall and your phone into the bank, and both charge. The bank itself accepts up to 30W of input over USB-C, which Anker presents as faster recharging of the bank.

Safety and travel

The bank is flight-approved, and Anker lists 24/7 battery protection under the name ActiveShield 3.0. A 10,000mAh bank is a normal carry-on item, and the protection suits something that lives in a bag and gets used on the move.

Extra ports

Besides the built-in cable, there is one USB-C port and one USB-A port. The USB-A port outputs up to 22.5W. These let you charge a second or third device, such as earbuds or a friend's phone, with a cable of your own.

Charging performance: fast for one device

The USB-C port and the built-in cable both deliver up to 45W. Reviewers say this charges phones and tablets quickly. One detail for iPhone owners: the maximum is 40W for the iPhone 17 series. Samsung Fast Charging 2.0 is also supported for compatible Samsung devices.

The 45W figure applies to single-device charging. When several ports are used at once, the total output falls to 24W max. Charging a phone from the built-in cable and earbuds from the USB-A port is fine. Expecting every device to charge at full speed is not.

A second caveat is heat. Reviewers note that output can throttle under sustained load because of heat. The temperature readout on the display lets you keep an eye on heat.

What experts like and what they criticise

The bank averages 8.1/10 across 4 expert reviews. TechRadar and Trusted Reviews each score it 4/5, G Style Magazine gives it 8.5/10 and DANAMIC gives it 7.8/10. It is also recommended in one independent expert buying guide.

Praise. Reviewers consistently like the cable you never have to carry. They also like the quick USB-C output, the informative display, pass-through charging, and the flight-approved capacity with battery protection.

Criticism. The common complaints are the 24W total when several ports are in use, throttling under sustained load, the thick body, and the loss of a key function if the built-in cable breaks.

Who should buy it

This bank suits people who charge one device at a time on the go. That means commuters, frequent travelers and anyone who has arrived somewhere with a bank but no cable. If you mostly top up a phone or tablet, the built-in cable and the 45W output (40W for the iPhone 17 series) cover most of what you need. The display also suits people who like to see exactly what is happening, including wattage and temperature.

It sits in the mid-range part of the market.

Who should skip it

Skip it if you need to charge a laptop or run several devices at full speed at once. The 24W total across multiple ports rules out the second use. If your pocket space is tight, the thick body may bother you. If you worry about a single point of failure, a bank with a separate, replaceable cable avoids the built-in cable risk.

How it fits in the power bank category

10,000mAh is a popular size for a daily carry bank, large enough for real use and small enough to take everywhere. The A1638's selling points are its retractable cable, smart display and pass-through charging. The trade-offs are size and sustained-load performance. If those fit your habits, it is an easy bank to live with.

Verdict: Anker Nano Power Bank A1638 review summary

The A1638 does what it sets out to do. It gives you fast, cable-free charging for a phone or tablet, with a clear display and sensible travel credentials. Be realistic about the limits: multi-port output drops to 24W, heat can throttle sustained charging, and the built-in cable is a single point of failure. For commuters and travelers who charge one device at a time, it is a strong, convenient choice, and the 8.1/10 expert average reflects that.

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