Redditor attaches ludicrous 30,000mAh battery to their Samsung Galaxy phone

Technician attaching Samsung battery to smartphone
(Image credit: Shutterstock / sasirin pamai)

Even the very best phones can sometimes leave you wanting when it comes to battery life, with today’s most premium handsets – think the Samsung Galaxy S23 Ultra and iPhone 14 Pro Max – topping out at around a day of heavy usage.

Naturally, bigger batteries come at the expense of portability – but that hasn’t stopped one Reddit user from attempting to answer the question: what would happen if you strapped an enormous power pack to the rear of a cheap smartphone? 

As spotted by 9to5Google, Redditor u/Downtown_Cranberry44 has performed some DIY wizardry to successfully attach a working 30,000mAh battery to their Samsung Galaxy A32 5G. Yes, you read that right – a 30,000mAh battery. For context, that’s six times the size of the Galaxy A32 5G’s original 5,000mAh battery, which already yields around two days of moderate use. 

You do the math: if you’re getting two days of juice from a 5,000mAh battery, a 30,000mAh battery should – on paper, at least – yield almost two weeks’ worth of battery life. There’s a good chance, then, that u/Downtown_Cranberry44 has in their possession the world’s longest-lasting smartphone. Check out some images of the modified device below:

Of course, this isn’t the sort of DIY modification we'd recommend performing yourself at home. For starters, the 30,000mAh battery pack looks to have made this particular Galaxy A32 5G nigh on unusable, adding around a pound (half a kilo) of weight and 3 cm of extra size to an otherwise slim and lightweight smartphone. 

The bigger concern, though, is one of safety. As 9to5Google notes, power packs of this size are more prone to leakage and exterior damage; there’s a reason you can’t board a flight with batteries any larger than 27,000mAh under current US law. 

For now, then, this sort of at-home experimentation is nothing more than that – we don’t expect to see Apple adding a massive batteries to the rear of the iPhone 15, for instance. But experiments like this can help us to appreciate just how much clever engineering goes into the neat packaging of c. 5,000mAh batteries in today’s smartphones.

In terms of the phones that offer the longest-lasting batteries in 2023, you’ll get around 16 hours from the Asus ROG Phone 6, and just over 13 hours from both the recently released Samsung Galaxy S23 Ultra and iPhone 14 Pro Max. 

If you do find yourself frequently left in the lurch with your own phone’s battery, consider checking out our ranking of the best portable chargers

Axel Metz
Phones Editor

Axel is TechRadar's UK-based Phones Editor, reporting on everything from the latest Apple developments to newest AI breakthroughs as part of the site's Mobile Computing vertical. Having previously written for publications including Esquire and FourFourTwo, Axel is well-versed in the applications of technology beyond the desktop, and his coverage extends from general reporting and analysis to in-depth interviews and opinion.  Axel studied for a degree in English Literature at the University of Warwick before joining TechRadar in 2020, where he then earned an NCTJ qualification as part of the company’s inaugural digital training scheme.

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