Recently, I had the opportunity to test an extended battery for the Nexus S by Mugen Power (used it on my Sprint version of the Nexus S). The phone (stock) is good but it doesn’t carry the greatest battery life, as you can only get about six hours of hardcore usage (playing music, browsing on 3G or 4G, downloading apps, checking mail, Facebook, Google+, Twitter and so on). When the battery power really becomes an issue for most people is during traveling. The Mugen extended battery helps fix that problem with a Li-Ion, 3.7v with a 3300 mAh capacity, compared to the stock Nexus S battery: Li-Ion, 3.7v 1500mAh.
Mugen’s souped up version delivers battery capacity greater than 2 times of the stock battery. Unfortunately, this butchers the aesthetics of the phone, as the extended battery is almost 2 times as thick. When I tested it, I kept my Nexus out of site because I was just too embarrassed with the size of the phone. And with the curved contours of the handset, the extended battery made it look like a miniature canoe. Okay, with beauty aside, the phone doesn’t feel awkward to hold, as it fits in your palms rather well.
Performance was graded according to my daily routine, which is moderate usage, like occasional auto sync, background data transfer, sync accounts: Google Apps ( Mail, Contacts, Calender), Google Account (Picasa, Google+), Twitter, and Linked In. I’d also run apps in the background, such as Skype, Google Voice, Google Maps, Foursquare, and Gtalk. The way I really consumed power was from obsessively checking up tweets and heading over to the stock news feed or Google Reader. Other than that, I’d view an occasional YouTube video or video podcast. I’m not a hardcore user by any stretch of the imagination.
All in all, with moderate usage on Sprint’s 4G network, I was able to last almost an entire day (24 hours). And even when the battery is tested on WiFi it performs very well, as you can probably get 6-12 hours of intense tethering or streaming. Besides its ugly bulk and thickness, the Mugen Extended Battery is a definite buy at just a shade under a 100 bucks.