Battery mystery in Google Nexus S

Ever since Day 1 with Google Nexus S, I never have the phone fully charged at 100% – the phone always claimed to be fully charged at 94%-97%, and charging the device overnight doesn’t help. Faulty battery?

Nope. Luckily my 1500mAh Lithium-ion battery in Google Nexus S seems to be pretty normal after I did some extensive studies on this phenomena. Not too sure it will occurs in all other Android devices, but apparently fully charged at the battery life of less than 100% in Google Nexus S is not something need to be worried.

In Byron G’s study, he did an extensive study on the charging and discharging conditions on his HTC Droid Incredible and figure out the reason of inconsistent battery drains, especially during a full charge. It’s a lengthy article, which is a pretty interesting one, so if you have about 15 minutes to digest it, do check it out.

As a summary, what I found in the study is that:

1. Modern phones with Lithium-ion battery are using different charging method compared to the older phone to reduce the damage on the battery during charging. Below explained why and how (as quoted in Bryon G’s study):

The time at which the battery stays at [maximum charge] should be as short as possible. Prolonged high voltage promotes corrosion, especially at elevated temperatures. [Source: Battery University]

2. Portable device is best to charge while it is turned off to allow the battery charged at a correct settings. Parasitic load can confuse the charger and hence might degrade the potential of the battery.

3. Even if some of the devices claimed to be fully charged at 100%, but a quick battery power depletion can occurs as the battery gauge is catching up with the reality. If your device is fully charged at less than 100%, but the battery life is depleted in an usual pattern, I would say there is nothing to be worried about.

And before you saying ‘No, my Nexus One doesn’t do this to me, you are definitely wrong!’, here comes the quote I got from xda-developers forum, where a member called swetland (Google Android employee) tells that why Google Nexus S is a little bit different from some other devices:

Yup — once the battery reaches full capacity the charger stops (to avoid undue wear on the battery). The battery will discharge down to ~90% before the charger kicks in again.

On Nexus One we were able to run off of wall power once the battery was charged, significantly reducing the speed at which the battery discharged once full, and improving the chances of it being 99-100% when you took it off the charger. Nexus S has a different charge circuit configuration which does not allow it to operate in this mode. [Source: Xda-Developers]

So, don’t worry if your Google Nexus S (or other devices) doesn’t fully charged at 100%, as it simply shows you the real battery power percentage. However, if your battery power depleted at an unexpected/weird manner, try the 10 tips for saving and improving battery life below (else you might have a bad battery if these tips have no effect).

Source: Byrong via Android Police

Battery Power Saving/Improving Tips

Adjust the screen brightness to the lowest (or acceptable) settings – Unlike Super AMOLED screen, Super LCD is tend to use slightly more battery power since it has a different way to display a pixel from Super AMOLED screen – in short, Super AMOLED screen doesn’t require power to display a black pixel. To squeeze every juice from a fully-charged 1500mAH battery, adjust the screen to the lowest brightness (or auto-brightness if you prefer) can definitely help in long journey. You can do this in the Settings > Display > Brightness or use the Power Control widget pre-installed.

Turn off the window animations – While it is cool to have all the window animations turned on, these animations will somehow use slightly more processing power, which in turn use extra battery power. And by turning it off, it won’t affect the Android experience whatsoever, so no harm done and you gain more battery power. You can turn off the window animations (or partially if you wish to) at Settings > Display > Animations.

Turn off the screen auto-rotation – If you rarely used Nexus S in the horizontal orientation (since there is still no homescreen in horizontal mode), it is recommended to turn this option off. It will not give you a huge extra battery power, but with the accelerometer turned off from detecting the device orientation, which eliminating the chance of accidental screen rotation, turning it off will still be useful. You can un-tick the Auto-rotate screen option at Settings > Display.

Decrease the screen timeout – Admit it, sometimes human tend to forget things – this includes leaving the screen turned on without using it. Unless the screen is intended to be turned on, else leaving it on without any activity with it literally means that it is a waste. Decrease the screen timeout to 2 minutes, in my opinion, having the best balance between usability and power consumption. If you wish to have the screen lit up a little bit longer eg. When using the F1 2011 Live app, you can always easily increase the screen timeout. For adjust the setting, you can navigate to Settings > Display > Screen timeout.

Close unnecessary running services/apps – Thanks to the Gingerbread in Nexus S, there is now a better battery power management tool available to the user. Using this tool, Nexus S user can closely monitor the battery power depletion pattern, as well as understand the power consumption for each running apps. If you found some unnecessary apps in the running list, turn them off/force stop them. Even though they don’t seem to be running, but they might cause some significant drop on the battery life. I had once experienced it in my Nexus S with the Facebook official app, even though I am not using it and my internet was turned off, but it still keep draining the battery power for no reason. Therefore, if you know you won’t be using the app anytime soon after the first run, turn it off. You can do this at About phone > Battery use; click on the unwanted apps and click Force stop button.

Turn off the vibration – Although sometimes it is undeniably that vibration can be quite useful, but it is well known for its high power consumption. If you are in a long journey, it is advisable to have vibration mode turned off. Other vibration related option such as haptic feedback, keypress feedback should be also turned off if you wanted to squeeze every juice from the battery. For vibration mode and haptic feedback, you can access the options at Settings > Sound Settings > Vibrate/Haptic feedback. For keypress feedback, access it from the keyboard settings which is located at Settings > Language & keyboard > Android Keyboard (or any keyboard you are currently using) > Vibrate on keypress.

Use 2G Network – It is also well known that the phone tends to drain battery power faster if 3G mode is turned on – no exception for Google Nexus S. If you are in a bad 3G reception area, or you are well aware that you are not going to use the 3G connection, use 2G network instead. It won’t affect your call or text messaging services, but you won’t be able to use 3G services such as the internet. Nevertheless, it is pretty easy to enable the 3G network if it is needed. To use 2G network only, go to Settings > Wireless & networks > Mobile networks > Use only 2G networks.

Use Airplane mode – Airplane mode is an option for the user to disable all the network radios (or wireless connection) in the phone while in the airplane since there will be no signal available for the phone. However, if you are in an area that has a very bad network reception, or you won’t be able to use the calling/text messaging/internet for a period of time (for some reason), Airplane mode is also suitable to be used. Why Airplane mode? If you are in a bad network reception area, chances are your device always tries to seek for a better signal, and such repetitive action can drain the battery power quite dramatically. Airplane mode turns off the network searching, and in turn, saving battery power for better usage. To turn on the Airplane mode, go to Settings > Wireless & networks > Airplane mode, though please be aware that you won’t be able to receive any calls or text messages since your phone is now basically isolated from the cellular network.

Turn Wi-Fi/Bluetooth/NFC/GPS off – Nowadays, there are more and more communication devices equipped in the smart phones. While it is great to have them on board, but there is a trade-off – high battery power consumption. Besides the usual Wi-Fi, Bluetooth and GPS available in most of the Android devices, Google Nexus S is also equipped with NFC, and for the current situation, NFC is still pretty new and lack of practical use, therefore it is advisable to have it turned off to save battery power. Some goes to Wi-Fi, Bluetooth, and GPS, turn them off if they are not going to be used anytime soon. You can turn them on/off at the Power Widget, or at Settings > Wireless & network/Location & security.

Bump Charge – If you really in need of the full capacity from your battery,  bump charging might be the one for you, though I must inform that it will wear your battery faster, and you will need a replacement battery sooner than usual. In Bryon G’s study, he did some experiment on the bump charge and the outcome is positive. If you are interested in the procedure to do bump charge, check out his study, but once again, I must warn you that it will degrade your battery faster, and ONLY do this when you really need it.

Use the device. Charge the device. Whenever you can.

While it will be great if your device can last for few days to one week (which obviously smartphones nowadays can’t achieve this yet), but I like to reemphasize what Bryon G advised to his reader:

Beyond that, the best advice I can offer is to stop paying such close attention to your battery gauge and to just use your phone. Charge it whenever you can, and then stop obsessing over the exact numbers. If you really need more usage time, buy an extended-capacity battery and use it normally.

So, use your Google Nexus S at the full potential if you are able to charge it regularly, as explained in Battery University:

Lithium-ion does not need to be fully charged; a partial charge is better. [Source: Battery University]