Complete Guide to Recommended Mobile Battery Manufacturers and the Best Models

On the go, you want to quickly charge your smartphone or tablet. That’s where portable batteries come in. However, the market is flooded with numerous products from various brands like CIO, Anker, UGREEN, Elecom, and more. Capacity, charging speed, size—there are so many points to consider that it can be confusing to decide which one to buy.

In this article, we thoroughly test 49 models, including the latest products from popular brands. We compare them from five perspectives: actual capacity, portability, charging speed, device charging speed, and charging time of the battery itself. We carefully select and introduce recommended mobile batteries that are truly usable.

Testing Methods and Key Points

For this comparison, we focused on the following five aspects:

• Accuracy of actual capacity: How closely the listed capacity matches the real usable capacity
• Portability: Measuring thickness and surface area to see if it fits in pockets or bags
• Smartphone charging speed: Maximum output measured in real tests
• Battery charging speed: Time taken to recharge the battery itself
• Wireless charging performance: Charging speed on compatible devices

Tips for Choosing Without Mistakes

When selecting a mobile battery, it’s important to consider not just capacity but also how it fits your daily usage. If you carry it every day, a slim design is essential. For those who travel frequently, fast charging support is a must. For long trips or extended outings, prioritize large capacity. Also, a capacity of over 80% of the listed value is considered excellent.

Carefully Selected Mobile Battery Rankings

1st Place: SMARTCOBY Pro SLIM CABLE (CIO)

Actual capacity 75.98%, slim design perfect for daily use

Score: 4.6 / Price: 5,980 yen

CIO’s SMARTCOBY Pro SLIM CABLE is a compact, cable-integrated mobile battery. Its biggest advantage is the high accuracy of actual capacity. Measured at 75.98%, it reliably delivers the number of charges expected from the catalog specs.

With a thickness of only 1.8cm and a surface area of 63.77cm², it’s remarkably slim. It hardly gets in the way when carried with a smartphone. Fits easily into pockets, making it ideal for daily commuting or school.

It supports fast charging up to 39W for devices and 35W for itself. You can quickly recharge it just before heading out, even if you forget in the morning. Combining usability and compactness, this is a safe choice if you’re unsure which to pick.

2nd Place: SMARTCOBY TRIO (CIO)

Three ports simultaneous charging for smartphones and laptops

Score: 4.59 / Price: 6,970 yen

CIO’s SMARTCOBY TRIO boasts a large capacity of 20,000mAh. It features 3 ports: 2 USB-C and 1 USB-A, allowing multiple devices to be charged at once.

Its actual capacity test showed 75.23%, a good result. The deviation from the listed capacity is small, providing expected charging power. It’s 3.0cm thick, slightly on the thicker side, but with a surface area of 65.68cm², it’s still compact enough to fit in a bag.

Its high maximum output of 71W is notable. It can fast-charge smartphones, tablets, and even laptops. Perfect for those who carry various gadgets on business trips or travel.

3rd Place: SMARTCOBY Pro SLIM (CIO)

10,000mAh capacity, ultra-thin at over 16mm

Score: 4.54 / Price: 4,818 yen

CIO’s SMARTCOBY Pro SLIM is impressively thin at just 16mm. It doesn’t add bulk over a smartphone, making it ideal for those who prioritize portability.

Its actual capacity is 69.47%, slightly modest, but 10,000mAh can fully charge a mid-range smartphone about twice. Supports up to 38W output for fast charging, and recharges at 35W, so even if you forget to charge overnight, you can do it in the morning.

Highly recommended for those who want an ultra-thin battery to carry daily in their pocket.

4th Place: Uno Cable-Included Mobile Battery (UGREEN)

High accuracy with 82.26% actual capacity, display for charging status

Score: 4.53 / Price: Check details

UGREEN’s Uno series is highly rated for capacity accuracy, with an actual capacity of 82.26%. Very reliable compared to the catalog specs.

With 10,000mAh, it’s only 2.0cm thick and has a surface area of 80.68cm², making it compact. Supports simultaneous charging of three devices, and features a display showing remaining power in numbers. Max output of 35W for quick smartphone charging, and 30W for itself. Great value for money.

5th Place: Zolo Power Bank 10000mAh 30W MagGo (Anker)

Supports MagSafe for iPhone, wired fast charging at 33W

Score: 4.52 / Price: 5,990 yen

Anker’s “Zolo” is a rare wireless charging-capable mobile battery. Compatible with MagSafe, it can attach magnetically to iPhone for charging.

It achieves a high actual capacity of 86.69%. Wired charging output is 33W, sufficient for fast charging, while wireless is 7.5W—slower but convenient for quick top-ups at cafes. Ideal for iPhone users considering wireless charging.

6th Place: Elecom EC-C44LBK Mobile Battery

Three ports, maximum 67W output suitable for laptops

Score: 4.51 / Price: 6,999 yen

Elecom’s EC-C44LBK features 2 USB-C and 1 USB-A port. Actual capacity is 78.20%, ensuring reliable performance even when charging two smartphones simultaneously.

Its high output of 67W supports fast charging for smartphones and laptops. Recharging the battery itself is also quick at 67W, making it suitable for busy mornings. Perfect for charging multiple devices on the go.

7th Place: SMARTCOBY Ex03 SLIM PLUG & CABLE (CIO)

Built-in AC plug, charges both battery and devices simultaneously with a socket

Score: 4.48 / Price: 5,780 yen

CIO’s Ex03 features a foldable AC plug, making it a 3-in-1 device. It includes a USB-C cable, allowing charging of the battery and devices while plugged into an outlet.

High-precision capacity at 82.28%. Slim at 2.2cm thick with a surface area of 73.21cm². Supports fast charging up to 36W. Well-balanced for travel, eliminating the need to carry separate chargers and batteries.

8th Place: MagFlow PB773 (UGREEN)

Qi2 compatible, 25W wireless charging, up to 36W wired charging

Score: 4.48 / Price: 6,825 yen

UGREEN’s MagFlow supports Qi2 wireless charging with 25W output, providing wireless speeds comparable to wired charging.

Wired charging can reach 36W, suitable for quick top-ups. Actual capacity is 73.66%. Size is compact at 2.1cm thick and 77.87cm² surface area. Ideal for those seeking both high performance and portability.

9th Place: Power Bank 10000mAh Fusion Built-In USB-C Cable (Anker)

3-in-1 with AC plug, actual capacity 83.73%

Score: 4.47 / Price: 7,990 yen

Anker’s “Fusion” series combines a USB-C cable and AC plug in one device. Actual capacity is 83.73%, very close to the listed value, ensuring reliable performance.

Outputs up to 35W for fast charging of both device and battery. Thickness is 3.1cm, but with a surface area of 55.34cm², it remains compact enough for bags.

10th Place: Prime Power Bank 9600mAh 65W Fusion (Anker)

Foldable plug, up to 67W output for fast charging

Score: 4.46 / Price: 14,990 yen

Anker’s premium “Prime” model features a foldable AC plug, keeping outlets tidy.

With an actual capacity of 81.31%, it offers high accuracy. Supports up to 67W output, compatible with smartphones, tablets, and laptops. Fast recharging of the battery itself makes it reliable for sudden trips. It’s expensive but offers top performance and multifunctionality.

Which Brand Do We Recommend?

Brands that frequently appear in the rankings include CIO, known for accurate capacity and slim designs—ideal for daily carry. Anker is highly reliable with a wide lineup. UGREEN offers high capacity accuracy and great value, perfect for budget-conscious users. Elecom provides peace of mind as a Japanese manufacturer.

Each brand has its strengths and weaknesses, so choosing based on your usage scenario is key. For daily carry → CIO’s slim model; for travel or business trips → Anker’s large capacity; for cost performance → UGREEN. Matching your needs to the right brand ensures you won’t make a mistake.