Anker A1638 Review: Built-In Retractable Cable & 45W Fast Charging
The Anker A1638 Nano Power Bank combines a 10,000mAh capacity with a convenient built-in retractable USB-C cable and 45W fast charging, making it a standout portable power solution for smartphones and tablets.
By Elvis Dicki
Updated October 21, 2026
In the crowded market of portable power banks, the Anker A1638 Nano Power Bank aims to carve out a niche by addressing a common pain point: cable clutter. This 10,000mAh, 45W-capable portable charger distinguishes itself with a built-in, retractable USB-C cable, promising a streamlined and tangle-free charging experience. Designed for the on-the-go user, from frequent travelers to daily commuters, it targets those who need reliable, fast top-ups for their smartphones and tablets without the hassle of carrying extra cords. The bottom line is that this power bank prioritizes convenience and portability without sacrificing charging speed.
The device’s core proposition lies in its integration of a durable, retractable cable directly into its compact chassis, a feature that directly responds to user feedback seeking simpler solutions. It’s positioned as a go-to accessory for iPhone, Samsung Galaxy, Google Pixel, and iPad users who value a minimalist carry. While not intended for powering laptops due to its capacity, it serves as a robust companion for mobile devices, offering pass-through charging and a smart display for real-time status updates. This review will analyze its specifications, design, performance based on available data, and owner feedback to determine if its unique approach delivers on its promises.
Prime Anker Nano 10000mAh 45W Power Bank
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Anker A1638 at a Glance
| Specification | Detail |
|---|---|
| Model Number | A1638 |
| Battery Capacity | 10,000mAh |
| Max Output Wattage | 45W |
| Built-in Cable | Retractable USB-C |
| Additional Ports | USB-C & USB-A |
| Dimensions | 3.21″ L x 1.99″ W x 1.42″ Th |
| Weight | 8.16 oz (231 g) |
| Key Feature | Pass-Through Charging |
| Safety Certification | Flight-Approved |
| Warranty | 24 Months |
Design and Build
The Anker A1638 is engineered with portability as a primary focus. Its dimensions of 3.21 by 1.99 by 1.42 inches and weight of just over eight ounces make it notably compact, described by the manufacturer as 16% smaller than standard power bank models. This form factor is designed to fit comfortably in a pocket, bag, or even a coat pocket, though some owner reviews note its block-like shape can feel slightly bulky compared to ultra-flat alternatives. The build incorporates a smart display on one face, which shows the remaining battery percentage, input/output wattage, and battery cycle count, providing clear at-a-glance information.
The most distinctive design element is the integrated retractable USB-C cable. Engineered to withstand over 20,000 bends, this feature eliminates the need to carry a separate charging cable, directly addressing the issue of tangled wires and forgotten accessories. The unit also includes a lanyard loop, which owners find useful for retrieving it from bags or for hanging storage. The construction feels durable to users, with a premium aesthetic finish, though there is a noted concern about the vulnerability of the digital display if the device were to be dropped. The available color options, including black and light blue, help with quick identification among other tech gear.
Performance and Features
Charging Speed and Capacity
The Anker A1638 offers a maximum single-port output of 45W, which supports fast charging protocols for compatible devices. Manufacturer data states it can charge an iPhone 16 Pro to 50% in approximately 27 minutes. The 10,000mAh battery capacity provides usable power, though it’s important to note the manufacturer’s clarification on energy conversion: due to circuit losses, a fully charged unit delivers approximately 5,500mAh to 6,500mAh of usable power. This typically translates to about two full charges for a modern smartphone. The power bank itself can be recharged at up to 30W input, reaching a full charge in around two hours.
Connectivity and Ports
Connectivity is a major strength. The built-in retractable USB-C cable is the centerpiece, capable of both output for charging devices and input for recharging the power bank. This dual functionality is highly praised by owners. Additionally, the device features two physical ports: a USB-C port and a USB-A port. This allows for charging up to three devices simultaneously (using the built-in cable and both ports), though the total output is shared and reduced when multiple devices are connected. The wide compatibility covers the iPhone 17/16/15 series, iPad, Samsung Galaxy, Google Pixel, and other USB-C devices.
Key Operational Features
Several features enhance the user experience. Pass-through technology is a significant one, allowing the power bank to charge a connected device while the power bank itself is being recharged. This adds considerable versatility for users at a desk or near an outlet. The smart display provides real-time data on charging status, which aids in planning usage. Advanced battery care and 24/7 protection circuits are included to guard against overheating, overcharging, and short circuits, contributing to the device’s safety and longevity. The unit is also flight-approved for travel.
Setup, Support and Ownership
Setup is straightforward, requiring no technical expertise. Users simply pull out the retractable cable and connect it to their device, or use the additional ports with their own cables. The included welcome guide provides basic instructions. Ownership benefits include a 24-month warranty from Anker, backed by their customer service, which is frequently mentioned positively in the broader context of the brand. There are no firmware updates or software to manage. While the built-in cable reduces the need for accessories, users still have the option to use their own USB-C or USB-A cables with the available ports for different charging scenarios or to connect multiple devices.
Long-term ownership considerations revolve around the durability of the retractable mechanism and the battery’s lifespan. The manufacturer claims the cable is tested for over 20,000 bends. The smart display shows battery cycle count, allowing users to monitor the health of the internal battery over time. As with all power banks, performance will gradually degrade with repeated charge cycles. The compact design and integrated cable mean there are no user-replaceable parts, so the entire unit would need replacement at end-of-life. For more insights on durable tech gear, explore our Tech Gear section.
What Owners Say
Owner feedback for the Anker A1638 is overwhelmingly positive, reflected in its high average rating. The vast majority of reviews award five stars, with praise concentrated on several key areas. The convenience of the built-in retractable cable is the most frequently highlighted benefit, with owners loving the elimination of a separate cord and the tangle-free storage. The fast charging speed, particularly for recent smartphone models, is also consistently commended, with users noting how quickly it tops up their devices.
Owners appreciate the compact, portable size and the usefulness of the smart display for monitoring power levels. The pass-through charging functionality and the ability to recharge the bank with its own built-in cable are seen as major advantages. Critical feedback is minimal but includes observations that the blocky shape, while compact, isn’t as pocket-friendly as flatter designs, and there is a general caution about potentially damaging the display if dropped. A small percentage of lower ratings mention receiving fewer charges than expected, which aligns with the manufacturer’s notes on energy conversion loss. The sentiment confirms this product successfully solves a specific annoyance for mobile users. For other highly-rated tech accessories, check out our Reviews hub.
Pros and Cons
Pros
- Integrated retractable USB-C cable eliminates cord clutter
- Compact and lightweight design enhances portability
- Supports fast charging up to 45W for quick top-ups
- Pass-through charging allows simultaneous device and bank charging
- Smart display provides clear battery and wattage information
- Robust safety features and flight approval for travel
Cons
- Not recommended for charging laptops due to capacity limits
- Usable capacity is less than 10,000mAh due to conversion loss
- Output is reduced when using multiple ports simultaneously
- Block-style design can be less pocketable than flat banks
- The digital display could be vulnerable if dropped
- Limited to charging smartphones and tablets
Who Should Buy It (and Who Should Skip It)
The Anker A1638 is an ideal purchase for smartphone and tablet users who prioritize convenience and portability. It’s perfectly suited for frequent travelers, daily commuters, students, or anyone tired of managing separate charging cables. Its fast-charging capability makes it excellent for users with compatible iPhone, Samsung, or Pixel devices who need a quick battery boost during the day. The pass-through feature also benefits those who work at a desk and want to keep their device and power bank charged simultaneously without needing two outlets.
This power bank is not the best choice for users whose primary need is to charge a laptop, as the manufacturer explicitly does not recommend this use case due to capacity and thermal limitations. It may also fall short for those who require maximum possible charges from a single power bank cycle, as the conversion loss results in fewer full charges than the raw capacity might suggest. Users who need to charge three or more devices at full speed simultaneously should look for a unit with higher multi-port output. Finally, if your usage demands an ultra-flat, credit-card style power bank for front pants pockets, the blockier form factor of the A1638 might not be the optimal fit. For buyers focused on specialized tech, our AI & Software coverage offers different perspectives.
Final Verdict
The Anker A1638 Nano Power Bank successfully executes a clever concept by integrating a reliable retractable cable into a capable fast-charging power bank. This single design decision transforms the user experience, removing the most common hassle associated with portable power: the separate, often forgotten or tangled cable. When combined with its genuinely compact size, 45W fast charging support, and useful features like pass-through charging and a smart display, it creates a highly compelling package for its target audience. The performance specifications and overwhelmingly positive owner feedback confirm that it delivers on its core promises of convenience and speed.
While it has understandable limitations—it’s not for laptops, and energy conversion means you get less than the stated capacity—these are clearly communicated and are trade-offs for its portable form factor. For anyone seeking a reliable, fast, and supremely convenient power source for smartphones and tablets, the Anker A1638 stands out as a top-tier option. It exemplifies how thoughtful design can solve a real-world problem, making it a recommended choice for most mobile users. Its strengths align perfectly with the needs of modern, on-the-go lifestyles, solidifying its place as a valuable piece of everyday tech gear.
FAQs
How many times can it charge my phone?
Due to energy conversion loss in the battery cells and circuitry, the usable power from a fully charged Anker A1638 is approximately 5,500mAh to 6,500mAh. For a modern smartphone with a battery around 3,000 to 4,000mAh, this typically translates to between one and two full charges. The exact number depends on your specific phone model and its battery health.
Why isn’t my phone charging at 45W?
The power bank supports up to 45W output, but not all phones can accept that much power. Even for compatible phones, the charging speed will intelligently slow down to protect the device’s battery as it heats up or nears full capacity. It is normal for the smart display to show a wattage below 45W during charging. The maximum speed is typically achieved when the phone’s battery is at a low percentage.
Can I use the built-in cable to recharge the power bank?
Yes, a key feature of the built-in retractable USB-C cable is its two-way functionality. You can use it to charge your devices from the power bank, and you can also use it to recharge the power bank itself by plugging the cable into a compatible wall charger. This eliminates the need for a separate cable for recharging the bank.
Is it safe to take on an airplane?
Yes, the Anker A1638 is flight-approved. Its 10,000mAh capacity is well under the typical 100Wh limit enforced by most airlines for carry-on luggage. You should have no issues bringing this power bank on a plane in your carry-on bag. Always check specific airline regulations, but this model is designed to comply with common travel standards.
About the author
Elvis Dicki writes reviews and buying guides for CyberSecLabs.