The usage of Smart phones has grown very rapidly in the past 4-5 years. Now there are smart phones available with different O.S, different hardware, sizes and colors. But the only main problem that people face today with these smart phones is with the battery backup. As the processing power, or the function of a smartphone rises, it drains the battery. Feature phones can be used for days at a stretch basically because there is no high processing power required. But now, the Smartphone is not just used for making calls and texting, its mainly being used as an internet communication device and for running various applications and games. This new trend burns up more battery. The only solution available for people is to increase the size of the battery for their devices. But the manufacturers of these devices very rarely bring out battery alternatives for their phones. The only way out is to use Mugen Powered batteries which come in various sizes and Milli amperes.

Mugen Powered batteries have become popular in the Android world mainly because these devices use loads of battery and Mugen has the solution whether it be a slight increase in mAh without any modification to your device or a heavy weight Mugen battery like this 4000 mAh battery we are reviewing today, which increases the weight and size of your device and the best part is that Mugen also supplies the back cover for these heavyweights. Enough of the introduction, let’s dive into the review now.

Look and feel:

The battery is really huge. It has to be,  considering the power and size of the battery slot on the Galaxy Nexus. The extended battery is a bit heavy and very thick. The battery is around 0.5″ thick and adds more thickness to the device.

The cover looks like a cheap replacement of the original GN back cover (Yup someone found a cheaper material than Samsung’s). The cover texture is just like the original cover and has a thumb sized gap for the camera. The kick stand is a well thought idea for cover but not when it is for a device with a fat 4000 mAh battery. It is very wobbly due to the weight and looks like it will fall down with a simple touch. The battery cover fits right in after the battery is inserted and does not seem to fall off. I got used to the huge size after about 3 days of using the extended battery with my phone. But sometimes you wish that it was more slim.


At first I was using the Mugen battery on Android 4.0.2 which has many battery drain issues and was shocked of the 4000 mAh battery getting drained just under a day. All I did was made about 5-6 calls, played Angry birds Space for 15 minutes, browsed the internet for about 2 hours, watched an episode of House, played some music using PowerAMP for 20 minutes. I had also kept the auto sync on for my 4 Gmail IDs, Twitter and Facebook. Also had the Google reader and Taptu news Widgets set to every hour refresh.

The battery gave me a lot better performance with Android 4.0.4 update where the battery was alive for more than 2 days and I used a lot of google maps and tweeting besides the above mentioned activities on those 2 days. I also carried the extended 4000 mAh battery with me when I was travelling from Mumbai to Kerala which is a 1.5 day train travel, I used my Galaxy nexus to listen to songs, watched a movie, checked some mails, sent some tweets and it was really useful and a life saver. The worked for a few hours even after I reached Kerala.

Another great thing about Mugen is that they also have a battery calibration application for Android where we can set two different calibrations, one for your extended battery and the other for the original one, so when you are switching the battery the app helps the device to calibrate with the battery just inserted.


The 4000 mAh battery is well worth the buy, coupled with the original battery you can get around 3 days worth of juice out of your Galaxy nexus. The only issue I had with this battery is that it made my GN huge and heavy. It is very difficult to use it as a daily driver. The original battery is enough for daily use.

The 4000 mAh battery is best when you are travelling and using too much of Gmaps and internet data. It’s best when  you are going long distance and need your phone to work for a long time for entertainment, checking mails etc. Performance wise this is a great battery to carry with you so that you can switch to it whenever you are in need as you don’t know when you will have to travel. I always have this fully charged 4000 mAh battery in my bag every day. I totally recommend all galaxy nexus owners to get this extended battery which is really really useful. So, if you have a Galaxy Nexus you must go and buy this battery now – you can get yourself one here.

Note: This only works with global unlocked Samsung Galaxy Nexus for other variants please check here.