A 20,000 mAh power bank is usually a brick. INIU prints “Smaller” on the box of this one, and it really is small in comparison to other 20,000 mAh power banks.
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I take it into the rooftop tent at night to charge my devices. During the day it goes back in the car, where I recharge it on our big lithium battery.
It’s the third 20,000 mAh power bank we’ve tested, after the VRURC and the Kings 20,000mAh.
What You’re Getting
A 20,000 mAh (74 Wh) power bank from INIU with two USB-C ports, a USB-A port, a percentage display, a built-in torch and a carry cord that doubles as a USB-C cable. It’s available in Black, Beige, Blue, Green and Red.
The good
- Really small for a 20,000 mAh power bank
- Carry cord doubles as a USB-C charging cable
- Feels very solid
- Simple display: just the battery percentage
- Two USB-C ports plus one USB-A
- 4 solid charges of an iPhone 16
The not-so-good
- Only 15 W in total when charging more than one device
Quick Specs
| Spec | Details |
|---|---|
| Brand | INIU |
| Model | P51 |
| Weight | 320 gwith carry cord |
| Dimensions | 10.5 × 7.1 × 2.9 cm |
| Colour options | BlackBeigeBlueGreenRed |
| Capacity | 20,000 mAh / 74 Wh |
| Ports | 2 × USB-C (in and out)1 × USB-A (out) |
| Output | Up to 22.5 W from one port15 W in total with two or three |
| Input | Up to 20 W (USB-C) |
| Display | Charge percentage |
| Warranty | 3 years |
| Extras | LED lightCarry cord with built-in USB-C cable |
Size & Weight
This is where the INIU stands out. It’s really small in comparison to other 20,000 mAh power banks. It measures 10.5 × 7.1 × 2.9 cm and fits in the palm of my hand, and it weighs 320 g on my scale with the carry cord attached. That sits between our other two 20,000 mAh power banks: the VRURC at 255 g and the Kings at 377 g.
The carry cord
I really like the fact that the carry cord doubles as a USB charging cable. It’s a short USB-C cable: one end pulls out of the clasp and plugs into your phone. That means you always have a cable with the power bank, which is the thing that usually gets left behind.
Ports and charging
On the end are two USB-C ports and a USB-A port. Both USB-C ports work as input and output, so either one charges a device or recharges the power bank. Each port gives up to 22.5 W on its own, and that’s fast. I tested it: my iPhone 16 went from 2% to 60% in 27 minutes.
Plug in a second or third device and the total drops to 15 W, shared between them. For charging two phones overnight that’s fine. If you want speed, charge one device at a time.
Two USB-C outputs plus one USB-A is a good mix. Most of my devices are USB-C anyway.
I got 4 solid charges of my iPhone 16 out of it.
The power bank itself takes up to 20 W in. I recharge it during the day on the lithium battery in the back of the car.
Display, light and build
The display is very simple: it just shows the remaining battery percentage. That’s all I need from it. Press the button on the side and the number lights up behind the glossy panel on the front, so I can see at a glance whether it needs to go back on the car battery during the day or still has enough for another night in the tent. A percentage is a lot more useful than the four dots you get on most small power banks, where you never quite know if one dot means 25% or nearly empty.
Between the ports there’s a small LED light, and it’s handy in the rooftop tent at night. It isn’t bright enough to replace a head torch, but since the power bank is already next to the pillow charging a phone, it’s the light closest to hand when I need to find something in the dark.
The power bank feels very solid. The body is matt black with a glossy panel over the display, and it comes in Beige, Blue, Green and Red as well. The carry cord is thick and braided, which fits the solid feel of the rest, and it makes the power bank easy to hang from a hook in the tent or to pull out of a bag.
Conclusion: INIU Power Bank 20,000mAh
The INIU packs 20,000 mAh into a power bank that’s really small for its capacity and feels very solid. The carry cord doubles as a USB-C cable, the display simply shows the percentage, and the small LED light is handy. I got 4 solid phone charges out of it. With more than one device plugged in, the output drops to 15 W in total. I paid $50 for it. If you want a lot of capacity in a small package, it’s a very good choice.
For all the power banks we’ve tested side by side, see our best camping power banks guide.
A really small, solid 20,000 mAh (74 Wh) power bank with a simple percentage display, a carry cord that doubles as a USB-C cable and 4 solid phone charges.
Output drops to 15 W in total with more than one device plugged in. It’s the one to pick if you want a lot of capacity in a small package.
- Campers
- Hikers
- Travellers
Yes. I paid $50, and for that you get 20,000 mAh in a really small, solid power bank with its own cable in the carry cord. The Kings 20,000 mAh cost me about twice as much.
