Samsung Galaxy S4: how to double your battery life

Darien Graham-Smith November 14, 2013

DSC_1191-462x346 I love my Samsung Galaxy S4, but I don’t love its battery life. Samsung advertises “up to eight hours” of active use, but when I’m sitting on the tube playing a game, and my phone is constantly searching for a mobile signal that isn’t there, I swear that battery meter ticks down by 1% a minute. Having paid for a premium smartphone, I hate feeling like I have to carefully ration my use of it.

Samsung Galaxy S4: how to double your battery life

I can’t blame Samsung. You won’t do much better with a Nexus 5 or an HTC One. There seems to be an industry-wide consensus that slimness is king. Your phone might run out of juice by sundown, but while it’s spending the evening conked out in your pocket, at least it won’t ruin the line of your trousers.

High-capacity batteries aren’t manufactured or endorsed by Samsung

In fact, the S4 wins out over those rivals, because the battery compartment is easily accessible. This allows you to carry around a spare for emergencies – or, you can swap your everyday battery for a high-capacity replacement.

The idea comes with a few caveats. High-capacity batteries aren’t manufactured or endorsed by Samsung, so if you buy a cheap one and it blows up, your warranty probably won’t cover it.

And it’s not as if the wafer-thin chassis of a Galaxy S4 offers much room for a fatter battery. The beefiest drop-in replacement I’ve seen is rated at 3,300mAh. That’s certainly an improvement over the stock 2,600mAh battery, but – in my view – not quite enough of one to fully alleviate that lingering anxiety over running low.

Making room for a larger battery

Happily, there’s an alternative approach. US-based battery specialist Anker offers a high-capacity power pack that comes with an enlarged replacement back for the S4, enabling it to accommodate a massive 5,200mAh battery. (There’s a version for the S3 too.) I bought mine on Amazon for the bargain price of £18.

When I say an enlarged back, I mean enlarged. Snapping on the replacement cover more than doubles the thickness of the handset from 8mm to 16.5mm. Since the S4 is a big phone to begin with, you’re left with something that towers over Apple’s puny iPhone 5s:

I’ve found the extra bulk less bothersome than you might think, however. The extra depth seems to make the S4 sit more comfortably in the hand, and it’s not so chunky as to be laughable. A few friends have commented on my phone’s unusual thickness, but when I’ve explained that it’s to house an extended battery, most have considered it a jolly good idea.

And there’s no denying that it works. In the week since taking delivery of my 5,200mAh battery, I’ve been using my phone at least as heavily as usual, and I haven’t once come close to exhausting the battery. Even if I forget to charge the thing overnight, it’s no problem. At the time of writing, I’ve been using the phone for more than 30 hours on battery power and it’s still showing a 51% charge. (Update: The battery finally gave out after around 63½ hours away from the mains, having effectively given me three full days of use.)

The only disappointment is the replacement back itself. In shiny black plastic – or white, or blue – it looks and feels cheaper than the original polycarbonate cover. It also replaces the Samsung logo with the word “ANKER” in bold capital letters, which makes me glad I’m no longer at school surrounded by Tipp-Ex-wielding wags.

The worst part is, much of it’s hollow. I had imagined that the extended battery would fill the casing, but nope – there’s nothing but air behind the top and bottom of the back. As a result, when I grip the phone tightly it flexes inward, sometimes making a creaking noise that certainly doesn’t sound like a flagship smartphone.

Still, when the supersized battery inside lets me forget all the caveats and qualifiers that usually attach to the idea of “all-day usage”, I’m willing to put up with a lot. For sure, I’ll take a phone that flexes any day, over one that gives up the ghost on the bus ride home.