UGREEN 48,000mAh 300W Power Bank review. It's big, it's heavy, it's not really 48,000mAh

UGREEN's latest large-capacity power bank comes in boasting 300 watts of power output with an advertised capacity of 48,000mAh.

On paper, UGREEN claims that this is enough to charge a Samsung Galaxy S23 Ultra 7.1 times, an iPhone 15 Pro 10.8 times, or a MacBook Air M2 15" 1.1 times. Eagle eyes will notice something odd because, using the S23 Ultra as an example, it has a 4855mAh battery, so technically it should be able to be charged (in an ideal world) nearly 10 times from a power bank that has a 48,000mAh capacity, though this is never really the case due to overheads and efficiency losses.

I put this to the test with my Galaxy S24 Ultra, which has a 5000mAh battery, so a nice even number to test with. More on this later.

The power bank supports USB-PD 3.1 spec, and is PPS compatible, so Samsung devices will see it as a Super Fast Charging 2.0 power source.

It is also compatible with most other widely accepted fast charging standards up to a maximum of 140W output from a single Type-C port.

Specifications

Build quality

Just like UGREEN's other products, the build quality and heft of this power bank is excellent. It feels like a premium bit of kit and looks it, too.

There is a carry handle, which is handy, especially when using the LED lamp on the side, which is perfect for those who trek outdoors or for camping and beyond. It seems to be ideal for emergency situations, even around the house during a power cut or keeping in a workshop or car boot...

Performance

... I mention car boot because the cell chemistry used in this is LiFePO 4, which is different from the usual Lithium-Ion cells found in other power banks. LiFePO 4 offers a longer cycle life, higher tolerance to temperatures and better reliability.

The technology is also known as LFP, and these battery types are typically found within the automotive industry in EVs. Interesting to see it trickle down into gadgets like this.

The longevity of a product like this using this cell chemistry means that the battery recharge cycle count is rated to 3000 cycles instead of the usual 500 before cell health degradation starts to become noticeable.

The downside to these safety and longevity advances in LiFePO 4 is that the energy density is lower than usual Lithium-Ion batteries, so dollar for dollar, you end up getting more usable capacity from a non-LiFePO 4 power bank, but they won't last as long over a longer period. Swings and roundabouts.

Testing with my Galaxy S24 Ultra, I was able to charge from 1% to 100% in a little over an hour. The display reported the full 45W supported by the phone during the core charge cycle until 80% was reached, at which point the power output trickled down for safety, which is perfectly normal. Once the phone was charged, the UGREEN's display reported that it had 84% battery remaining.

This means that 7,680mAh was consumed during this charging session. Remember that the S24 Ultra has a 5000mAh battery, so an extra 2680mAh is being lost to efficiency losses and the nature of the LiFePO 4 cell chemistry being used.

This also means that realistically speaking, I'll be able to recharge my phone a total of 5-6 times maximum, which is a bit short of UGREEN's claim of 7.1 for an S23 Ultra, which has almost the same size battery.

So, 48,000 doesn't really look as appealing as it originally did with this in mind, especially given the very high price tag. Still, as mentioned, this power bank will almost certainly outlast all other power banks due to its chemistry and retain its charge capacity for longer in the process if it is used for special occasions or emergencies.

The LED lantern is very usable too, with 115 hours of continuous runtime on the highest brightness, that's a good few days of emergency lighting.

Charging speeds

Whether mains or battery-powered, chargers with multiple outputs generally slow down when more than one port is in use as they share the rated total power output. For example, I have a 65W Anker mains charger which has two outputs, the moment I plug in another device to the second port the charge rate of 65W going into my laptop halves as the load has to be shared.

On paper, with 300W, UGREEN's power bank should have headroom for all five ports to be connected without drastically slowing down charging speeds to any given device. But if we delve into some of the additional information UGREEN shows on the product page, it becomes clear that output power sharing when certain combinations of ports are in use can drastically affect output power:

Gallery: UGREEN 48,000mAh charge rates

I've had the power bank on test for several weeks and still need to refer to the above diagrams to recall which port combos will give me the best charging output if I am charging multiple devices at the same time. It would have been nice to have this printed on the power bank housing itself.

The fastest charging devices I currently have access to are my phone and laptop, both totaling just over 100 watts. This combo had no issue with fast charging through the power bank.

Charging the power bank is possible up to 140W. At this rate, it takes 1.5 hours to fully charge. Sadly, no mains charger is included in the box, and at the time of writing, a typical charger that outputs USB-PD 140W costs £50 from a third-party brand. UGREEN's own model is up to £99, a rather large additional cost that needs to be considered if fast charging such high capacity is required.

Nevertheless, I was able to charge it using an Anker 45W charger in around 4 hours.

At no point did it generate any excess heat. It gets warm to the touch, but that was about it. For comparison, my phone gets hotter when fast charging. I suspect that if a 140W mains charger were used to charge the power bank, then it would get hotter.

Interesting to note that even at over 90% charged, the 65W/45W mains chargers continued charging at their max capabilities. The charging output typically tails off to single digits in this scenario with most devices. Maybe this is because the cell chemistry is different in this application, and throttling isn't required, or perhaps 65W-45W is the throttled range once full capacity nears. Without a 140W charger to test with, it's impossible to confirm this theory.

Conclusion

Ultimately I think this is what this power bank boils down to, something with a large enough capacity to charge a number of devices quickly all at the same time, and retain capacity for long term storage for use when needed.

The LED lantern strip on the side will no doubt be useful if there's ever a power cut or for those who spend time in the great outdoors, be it camping or something else.

I like some design choices on it, too, such as the rubber anti-slip feet on both the backside and underside, so if you wanted to have the USB ports facing upwards, then that is possible.

The carrying handle has already been mentioned, but again, it is a welcome design inclusion given the heft of this thing.

If there's anything I would have liked to see then it would be more than just one USB-C cable in the box, although cables are available everywhere these days, so I'd be nitpicking here.

I think UGREEN could have clarified the capacity better, though. Plastering 48,000mAh on the side and on the website gives the illusion that you are getting the full capacity in practice.

I also think that some other reviews of this power bank online missed the mark. It got slated for not being at its rated capacity, and I can see the reasoning behind that criticism. However, knowing its target use case and the long-term benefits, it's the kind of thing that will still be kicking many years down the line up to 3000 charge cycles. In contrast, other power banks will have degraded maximum capacity once they reach the usual 500 charge cycle range.

The way I see it, this is a power bank you buy for its long-term benefits and the safety and reliability that comes with it. It's a shame no mains charger is included in the box, at this price range I'd expect more than one cable, and a mains charger of at least 100W output so the power bank can be recharged at a fairly decent speed.