Most backpackers are carrying a powerbank on multi-day trips. As the need for additional power for a multitude of electronic devices increases, so does the search for the lightest and most efficient of high capacity ‘bricks’. Three Points of the Compass has a glance at a 20k mAh option from Nitecore.

Engineering and manufacturing company Nitecore were established in 2007. Based in China, they have regional stockists and outlets across the globe. Having built their name with the introduction of innovative torches (flashlights to our cousins across the pond) they diversified and now produce headlamps, chargers and other accessories. Three Points of the Compass has long been a fan of Nitecore products, especially their powerbanks. I used their F1 and F2 battery chargers and 18650 batteries extensively while backpacking and these made for some of the most compact and lightweight powerbanks then available. Nitecore then produced even lighter, smaller or more efficient devices and I looked at four options in 2021. Those were the Nitecore MPB21, Nitecore F21i, Nitecore NB10000 and Nitecore NB20000. I followed up with a review of the second generation of their 10000mAh powerbank, the NB10000 Gen 2, in 2022. Now, a year later, it is a development of their lightest 20000mAh powerbank that is attracting interest from lightweight backpackers wanting to include yet more power on trail for ever hungry electronics.

The Nitecore Carbo 20000 20k mAh powerbank has a lithium-ion polymer battery (Li-Po) rechargeable battery (confirmed to me by Nitecore). These batteries have a higher specific energy than other lithium battery types. Li-Po batteries are lighter, more robust, do not leak, charge quicker, heat less during charging and are more expensive to make than Li-Ion batteries. However, Li-Po batteries have a shorter life than Li-Ion.

Various forms of protection are built in and it is amongst the safest of powerbanks with overcurrent and overcharge protection, short circuit protection, over voltage and discharge protection. It also has thermal protection. If the powerbank gets too hot while discharging, it cuts off until the temperature reduces sufficiently.

Most previous Nitecore lightweight powerbanks have carbon fibre reinforced polymer in a surrounding frame, overlain with carbon fibre sheets. The Carbo 20000 has a different build that reduces weight, makes it stronger and less likely to split at the edges. The Carbo 20000 has a seamless (along eight edges) ‘carbon fiber reinforced polymer’ (CFRP) construction which lacks joins and doesn’t corrode. Despite having what is referred to as a unibody design, it has a front piece inserted into the moulded case. The body is strong enough to survive a 1.5m drop test, though I wouldn’t recommend that.

I much prefer the rounded edges and corners of the Carbo 20000 over the more angular forerunners. It is more comfortable in the hand and less likely to abrade the internal face of my waterproof electronics pouch carried on trail.

The Carbo 20000 weighs 296.1g on my scales. I’ll round this down to 296g. By way of comparison, a 20k Nitecore NB20000 weighs 326g. The smaller capacity Carbo 10000 mAh powerbank weighs 175g, and is heavier than its similar capacity NB10000 Gen 2, which weighs 151g. Two 10k NB10000 (total 20k) weigh 302g, and two 10k NB10000 Gen 2 (total 20k) also weigh 302g. So the Carbo 20000 is easily the lightest 20k mAh option available. It then comes down to connector ports and rated (usable) energy.

The two charge ports on the Carbo 20000 have yellow accents. These do four things- differentiate the powerbank from many previous Nitecore products, are easier to find in the gloom, strengthen an area that had previously developed issues under frequent strain, and finally, look good!

The NB10000 and NB10000 Gen 2 (both 10k mAh powerbanks) can deliver up to 6400mAh (two of either together delivering 12800mAh). A single NB20000 powerbank can deliver up to 13500mAh. A Carbo 20000 powerbank can also deliver up to 13500mAh, so is touted not only as the lightest 20000mAh powerbank in the world option, but also capable of delivering more energy per gram when compared to others in its lightweight stable.

As to the connector ports, the weight of the Carbo 20000 is kept down by keeping it very simple, with a single USB-A output and a single USB-C In/Out. This may not be enough for some. But remember that when using multiple out ports, the overall charge being delivered is split between them, so no extra output is actually attained. If you did want to charge two components with this brick, you will require a splitter cable. The ports have no covers so the powerbank is rated as IPX5, which is ‘weatherproof’ not waterproof as some advertisements imply. An IPX5 rating should mean that circuitry is protected from low pressure water streams from any angle for up to 10-15 minutes. So could, in theory, tolerate light to moderate rain.

The Carbo 20000 has five LEDs centrally positioned at the ‘business end’ of the powerbank. These are activated by pressing the power button. Four of the LEDs indicating approximately 25%, 50%, 75%, 100% power level. This is an improvement on the three blue LEDs found on the NB1000 Gen 2 10k powerbank, that indicate approximately 30%, 70% and 100% charged. A flashing blue LED indicates that the powerbank is almost depleted. Pressing and holding the mode button enables a safe low current charge for devices such as wireless headphones, headlamps, smart watches etc. This mode is indicated by lighting the fifth, white LED. This mode doesn’t actually decrease the power output. Some power banks may not recognise the low power draw from some devices and switch themselves off, by switching to ‘low power’ mode, all this does is keep the Carbo 20000 turned on and delivering a charge. You should always exit low power mode if you don’t require it as otherwise the power bank will remain switched on and even the low draw LED will eventually drain it. Leaving a phone charging overnight unnecessarily will do the same, a powerbank will continue draining once a phone reached full power.

The design of the power button on Nitecore powerbanks has been improved on earlier incarnations and now doesn’t protrude, meaning there is less chance of it being unintentionally depressed.

A small but important change made with this powerbank is that the technical information included on its side is now legible, unlike the tiny black on black text of previous Nitecore powerbanks.

The powerbank supports two-way Power Delivery (PD) 20W output and 18W input via USB-C and 18W Qualcomm Quick Charge (QC) 3.0 output USB-A. This permits faster, but not fastest, charging of batteries without damaging the internal components. Phone, powerbank and cable must be compatible to enable quick charging and this is becoming increasingly commonplace across most products. Though a very slight improvement of the input over the NB20000, there will be those who were hoping for better things such as a higher input for quicker charging as there is usually less time constraints on charging a device from a powerbank. It will take a long time to charge this high capacity brick. The Nitecore NB20000 can accept a 30W Fast Charge input and 45W output so is capable of charging laptops etc. Something the Carbo 20000 can not do. We shouldn’t be surprised if this is the next upgrade Nitecore make to the Carbo powerbank.

The powerbank is capable of ‘through charging’. It can be charged via the USB-C port whilst simultaneously charging a device via the USB-A port but you will need to carry two cables to achieve that. Alternatively, both outlet ports can be used simultaneously to charge devices but the maximum charge rate is split between the devices so fast charge would not be possible in this configuration (5v-3A maximum).

Specifications:

• lithium-ion polymer
• Dimensions: 124mm x 59m x 21mm
• Weight: 296.1g (quoted 295.5g +/- 5g), 10.42oz
• Capacity: 20000mAh (77W). 260.5mWh/g
• Rated energy: 13500mAh
• Input: USB-C: 5V-2.4A / 9v-2A
• USB-A Output: 5v-3A / 9v-2A / 12v-1.5A
• USB-C Output: 5v-3A / 9v-2.22A / 12v-1.68A

New products come with an 18-month warranty though you need to register the product online to achieve a six month extension on the standard 12 months. There is a unique verification code and an authentication QR code on the box for this.

Final thoughts:

While a powerbank is purchased primarily for the power it can hold and deliver, weight, bulk and additional features are also concerns for backpackers and the Carbo 20000 ticks many boxes. The Carbo 20000 has a relatively low weight when compared to just about all alternatives in addition to its built in protection. The rounded edges to the frame are simply a decent plus point. While a 20k capacity powerbank provides a lot of power, some backpackers want to charge multiple devices on trail. I recently met a chap walking John o’ Groats to Land’s End who relied on 44k mAh, that is a great deal of weight of powerbanks in the pack. Anything that can go some way to reducing such weight is going to be appreciated. That said, I would have preferred to see a higher input capability on this powerbank to reduce the time required in town etc. While many will complain of the reduction in the number of ports in the Carbo 20000, my needs are simple on trail and I prefer exactly what ports I require for charging and no more. With less ports there is less opportunity for moisture ingress and the weight and bulk of a powerbank is further minimised. Three Points of the Compass approves of many of the changes made to this ‘upgraded’ 20k powerbank over those that have preceded it. For longer trips where I am anticipating a great deal of phone/power use, the Carbo 20000 is likely to be a primary choice of powerbank for some years, at least until Nitecore improve both input and output capability.

Nitecore Summit 20000:

There is also a Nitecore Summit 20000 powerbank which at around 303g +/- 5g, is slightly heavier, has a similar capability to the Carbo 20000, with some additional features, such as a heating element, making it suitable for use in sub-zero conditions.

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