The benefits of having an extra battery in your phone case include a full charge when your iPhone’s internal battery runs dry plus protection from the usual knocks and bumps. The Dexim XPowerSkin battery case joins the gang of charger cases from the likes of Mophie, Phonesuit and Powerskin. At £70 it’s at the less-expensive end of the category, although we’ve seen the similarly named Powerskin Battery Case on sale online for less. Its battery capacity is rated at 2,000mAh, which should offer a full recharge of a fading iPhone battery. See our test results below to see if the battery case lived up to its potential. There are LED battery level indicators on the back of the case, so you can see how much extra power you have at hand. The button next to the LEDs makes turning on the case’s extra battery power a simple push. You recharge the battery case and the iPhone inside with the supplied Micro USB cable. The Dexim XPowerSkin looks quite cool in black and silver but the case feels more plasticky and fragile than the others we’ve tested. At 75g it’s lightweight, but no more so than most other battery cases. It comes in two parts: the battery back and a band that clips the whole thing together. It’s a little fiddly to snap together and infuriatingly difficult to pull apart again. If you sync your iPhone using a Lightning cable rather than wirelessly it helps if your battery case pulls off with ease. The XPower Skin is not for you if you want to slip your iPhone quickly out of the case. We felt like it or our fingernails might break at any time during the process. As you’d expect there are cutouts for the iPhone’s camera and other controls and switches. We found the Mute and Volume switches a little harder to reach than on the Mophie cases. Dexim claims that the XPowerSkin is “officially licensed by Apple” but this is doubtful as when charging a message pops up that “this may not be a supported device” – usually a sure sign that Apple hasn’t given its seal of approval. That said, it doesn’t stop the case charging your iPhone. Apple requires payment from manufacturers to have its special official accreditation, and non-official products often get the “not supported” message. Dexim claims that “with a 2,000mAh capacity it is able to charge your phone fully twice, and have a bit more left over for good measure”. This is a bold claim as other 2,000mAh battery cases we’ve tested offer around a little over one full charge on a run-down iPhone. Our tests bore our scpeticism out. Indeed it didn’t even give us a full recharge, and that’s poor if this is indeed a 2,00mAh battery. The battery pack will give an iPhone down to 10% charge a boost back to 75% – enough to last you till the next proper battery recharge but nowhere near the manufacturer’s claims. Simon was Editor of Macworld from the dark days of 1995 to the triumphant return of Steve Jobs and the launch of the iPhone. His desk is a test bench for tech accessories, from USB-C and Thunderbolt docks to chargers, batteries, Powerline adaptors and Fitbits.