[GUIDE] To Maximize Galaxy Nexus Battery

Search This thread

SrTapir

Senior Member
Jun 12, 2007
222
288
Barcelona
guiasapple.com
This guide is not meant to be as a whole and is not meant to be followed from beginning to end. There are several recommendations based on my own experience, some of them will give you big battery savings, some of them minor ones; I tried to recopile every config that helps to save battery, but every config is not suitable for everyone. (I´ll point it at the beginning of every section in bold blue).

You'll need a Rooted Galaxy Nexus, with a custom ROM and a custom Kernel.

The custom ROM will give you the ability to make a deep configuration of the device in terms of options. I'm actually using Liquidsmooth v1.25, but AOKP, CM9 and SlimICS have the same options (if not more) than my actual.

Some custom Kernels will give you the ability to change the CPU frequency and voltage, kernels are the main reason of some drainings or fantastic battery life, choose wise. :p

The normal Galaxy Nexus battery life is about 4 hours screen time. If you are not achieving this, the main reasons could be:

1. Some apps are draining your battery due to a continuous use (no deep sleep or continuous wake ups).
2. Screen too bright.
3. Bad kernels with draining problems.
4. Weak signal connections.

This guide is wrote by me, a simple user that is sharing his own experience of the last 4 and a half months with the device. Some statements may be wrong. I'll appreciate any positive recommendations in order to improve the guide and help the rest of the community to achieve the best battery life the device can give us.

I'm using actually Liquidsmooth v1.25 and PopcornKernel, in a GSM GNex with standrad battery (1700mAh), and I'm getting this results:

6929665280_40c34bfeff.jpg
6929665324_46c999617b.jpg
6929665376_2170980683.jpg
7075740719_27631fed51.jpg


SCREEN

Due to the big screen, this is one of the elements of the device that affects in a major way to the battery live. (Great Savings)

It has been checked that black themes have a great impact on the battery due to the fact that one black pixel does not consume any battery.

Some apps have a black theme option on them, if you choose it you will save some battery.

6929914768_16cc56ceb8.jpg
7075991409_33bab942d6.jpg
7075991915_f25d604d9f.jpg


On the other hand the brightness is the other part in the screen that has a big impact on the battery. In a logic way, less the brightness more the battery life. (Greatest Savings)

Now the latest ROM's have a new amazing feature, we can change the interval the sensor works to achieve the ambient light, reduce the brightness minimum value (that's by defect way too high in low light conditions), and customize your prefered light levels (that are too way too high in default configuration).

By reducing the sample interval sensor a bit and reducing the minimum value a lot we can achieved abetter battery life in a great manner.

7075992309_e6d4fb3a72.jpg
6929915858_857881832b.jpg
6929914864_3d26ee5092.jpg


Also adjusting the light sensor levels to a more reliable one's that are by far lower than the default one's we'll achieved a more optimize system that consumes less battery.

7095332465_3601a282b7.jpg
7095332753_1c405b7e3d.jpg
6949261896_cbbeee2aab.jpg


Note: This are my actual, after 2 weeks of adjust, values but I'm still working on them, they are no 100% reliable.

CPU

The CPU is a great beast. In terms of battery is well adjusted, by as always, we can achieve a personal optimized system (this is Android, yeah!) that will balance performance and battery life. (Great Savings Underclock and Undervolt combo).

A very good speed and fluidness can be achieved with a very good optimized and well balanced performance-battery friendly system.. and yes, with the last advances in kernels and ROMs, we can have a perfectly smooth system with a top speed of 1000Mhz.

In the other hand Undervolt will help us to achieve a cooler system with some battery gain. With Undervolt we´ll limit the max. value of the Voltage for the specified frequency, if we have a kernel with Smartflex, this one we´ll allow lower voltages depending on the power need of the CPU.

Two important things:
1. It has been tested that the 700Mhz frequency is prefereable over the 300Mhz one, due to the drops on frequency signal of the phone.
2. Undervolt values are not the same for everyone, it can oscillate depending on the individual CPU. When I UV I always test my system with an Stability Test app.


6949261750_804a236691.jpg
6929916566_0cdc76a98e.jpg


Connections

GNex is a phone...also.. well, it's a super computer with phone capabilities. Due to the "always connected" philosophy the optimal baseband will save a lot of battery. An optimal Baseband and Radio (region optimized) will require less power and time to connect to the antennas and will have better connection always (less power irradiated). (Medium savings).

The Radio should be updated and region optimized, there's a magnificent post made by josteink that explains all the details concerning the Radios with links to every one available.(GSM)

[Radio] (GSM) Galaxy Nexus I9250 Baseband dumps collection & discussion

European Radio Recommended: XXKK6 (XXLA2 is giving too high "Phone Idle", resulting in drain problems)

For the CDMA version there is another magnificent post by ready5 with a compilation of every RADIO for the CDMA version of the GNex.

(CDMA) [RADIOS/HYBRIDS]*UPDATED* 4.0.4 FULL 2/6/2012 PLUS FRIED RADIO Halp!

In the GSM version on the other part the 3G, HSPDA consumes great great great battery juice. If you are not in WIFI and are not using the data connection, a great way to save battery life is changing from HSPDA or 3G to 2G networks (this is really noticeable if you travel a lot by car or train, cause you are continuing connecting a reconnecting from different radio antennas).

There's some ROMs as Liquidsmooth that allows when you are not on WIFI and after an specified delay, to change to 2G automatically (or low consuming) networks when you have the screen off. This is a great way to save battery when you are not at home, reducing the standby drain of the phone outdoors.

6930022404_caffa3af3b.jpg
.
ibvnJPgSbMGp0v.gif

The automatic 2G when sleep is a main function of Juice defender. Thanks to a1exus for recommendation.

In the CDMA version the LTE consumes also great great great battery juice. If you are not in WIFI and are not using the data connection, a great way to save battery life is changing from LTE to 4G networks (this is really noticeable if you travel a lot by car or train, cause you are continuing connecting a reconnecting from different radio antennas).

iURDNcSyxeYuq.gif

Thanks to thenickisme for this!

WIFI

Wifi has a crazy history on the GNex. After talking and talking, posting and posting, it has been tested that WIFI always on while sleep is the best way to achieve a longer battery life. (Medium savings).

iboaVtpFxNiwTU.gif


Also the new ROM's have amazing feature that change the WIFI interval (we normally stay at the same WIFI always), increasing the value will save batterty life reducing the continues scans that produce the WIFI Always ON requirement.

6929916302_0f560e0f47.jpg
6929916820_e7d77ec545.jpg
7075991537_7a40b48db3.jpg


Services and Apps

The best thing of Android is that we can configure anything, one of the best and underestimated feature is the Freeze or Service Uninstall. We did it before in Windows and we can do it now. Through the Apps section in Preferences or the mythic Titanium Backup we can disable or uninstall an internal function of the systems that is normally used, giving more resources to the system and in some cases, saving some battery. (Low to Minimum Savings).

There are some ICS functions that no everyone uses. For example, I don't use any Bluetooth, NFC, Google Voice, Google Search or Speech function of the system, freezing or uninstalling them will optimize our system giving some battery juice.

6929917548_ae837e78af.jpg
7075993573_8b1e8d5f02.jpg


Note: This is a dangerous thing if you don't understand what you're doing. Make always a Nandroid before Freezing or Uninstalling an essential function, just to be cautious.

According to the Apps we have to take in account the Background Syncing or Sync Interval, most of the time the apps don't need to be synced every 5 minutes, like weather, if we make longer updates we'll achieve a good saving battery related. (Great Savings if many apps with many connections).

6930263364_eb69f3503d.jpg
6930263474_66a7c85bc3.jpg


Widgets, 5 homescreens full of widgets updating in real time could be detrimental to the battery live, take care when adding widgets and as said in the previous paragraph, change every widget preferences to update in longer times than usually they have by default. (Great Savings if many apps with many connections).

Bad Apps are the one's that not allow our device to deep sleep or wake up continuously our GNex. There are several on the market, Readability for example is a new one that wake up continuously our device attempting to download new articles, on the other part, some time ago Widgetlocker had some problems not letting deep sleep the GNexus (don't know now). (Great Savings if there is an apps giving deep sleep or wake ups problems).

Pointing on this, the best way to know if any app is not behaving well in the system is through 2 apps:

- BetterBatteryStats, that will look for any wake up of the device while sleep.
- CPU Spy, that will tell us if the device is deep sleeping ok or not.

Other things

There are other things that will help us in a great or minor manner to save battery life.

Sync Data usage (Google services like contacts, bookmarks, etc..) consumes battery, if you limit this usage, you´ll gain some juice. The new ROM's in the Powersaver tag will allow you to limit this sync usage. (Low Savings).

7075991627_34b6c93b3c.jpg
7075992659_992e1651d9.jpg


The Dial Pad Touch Tones and Vibration affects battery also (yepp it's true, and in a great way!), disabling this features will give you some extra battery juice. (Low to Medium Savings with combo sound plus vibration).

6929916948_4013378d14.jpg


The Google Location services and Backup&Reset Data consumes great battery also, limiting this services will gave you some extra juice. (Medium Savings).

6929917048_af1c4d9527.jpg
7075993311_4d5b1f4c3e.jpg


The last little thing that will help you save batt life will be the Automatic Date&Time option, disabling it will give you some extra juice also. (Lowest Savings, practical minimum).

6929917290_7fe93e36b9.jpg


Live Wallpapers, they are very nice but will drain your battery quickly. Static Wallpapers are preferred, and if posible, dark ones. (Medium to Great Savings).

Experimental

This are new tweaks that normally appear in new/advanced kernels, his use according to battery save is still not really tested or can have a detrimental on the physical conditions of the device/battery. Use them with caution or if you really know what you are doing.

[MOD][KERNEL]Battery Life eXtender (BLX), this is a tweak created by the popular Ezekeel and in his owns words: "Older types of rechargable batteries exhibited a 'memory effect' which made it neccessary to completely charge/discharge the battery when using to prevent degradation of the capacity. Modern Lithium-Ion batteries like in the Nexus S do not show this problem and thus it is not necessary to use the battery in complete (dis)charge cycles. In fact on the contrary, it is commonly accepted that both very low and very high charge states accelerate the degradation of the battery capacity (that is why you should store Li-Ion batteries at around 40% charge).

While a low charge state can be simply avoided by charging the device more often, the battery in the Nexus S by default is charged to around 95% capacity and I could not find any app or tweak to stop the charging at a lower capacity. Thus the only way was to use the manual override and pull the cable which is annoying since one had to monitor the charge state."
(Unknown Savings).

Galaxy Nexus is charged by default to the 96% of this capacity, with this new tweak you can gain this 4% (don't know for sure if you can get the 101%) of battery life, in 4 hours screen time, more or less 10 minutes, but it can be detrimental on the long way to the battery physical life.

You can found this tweak in the last nightly of Franco's Kernel, and can be activated via his own app.

6934120678_4987c66b12.jpg
6934079422_3365b0af5d.jpg


You can find more information in Ezekeel post here at XDA.

[MOD][KERNEL]Undervolt of IVA and CORE Voltage, new patches let undervolt the IVA (hardware media decoder) and CORE (GPU Voltage), I'vce been playing with this all the day and I've managed to undervolt a 15-20% de original frequencies. (Unknown Savings).

I understand that with this we are limiting the maximum voltage they can use, letting them to use lower ones according to GPU load. I'm not sure at this (GPU uses smartflex also ¿?) but with a descent of 20% on the voltage could result in longer battery life while playing games or seeing movies.

I'll try further undervolts, but this are my actuals on a stable system.

6949261248_e706bf914d.jpg
7095332909_143ebafa90.jpg


You can play with this voltages via the last nightly of Franco's Kernel, and via his own app.

Take care playing with this, could result in system instabilities, reboots, freezes, etc.
 
Last edited:

SrTapir

Senior Member
Jun 12, 2007
222
288
Barcelona
guiasapple.com
Links of interest

- BetterBatteryStats, A high battery drain is often a limiting factor for a great user experience.
With BetterBatteryStats you can analyse the behavior of your phone, find applications causing the phone to drain battery while it is supposed to be asleep and measure the effect of corrective action.

- CPU Spy, This is a simple app to display the time the CPU spends in each frequency state. This can be a useful tool in diagnosing battery problems or tweaking your over-clock settings.
It also displays the current kernel information.

- StabilityTest, StabilityTest is a stress-testing tool for android devices with error reporting.
StabilityTest is a CPU, GPU, RAM/memory stress-testing tool for your device, whether stock and unrooted (limited functionality) or rooted and overclocked with SetCPU, SetVsel or similar tools.


Extended Battery

At the end, the best way to extend the battery life is with an Extended Battery, they are not very expensive and only increase a little bit the thickness of the device. They can be bought at several places through the typical places as Ebay, Expansys or Amazon.

Important: Take in account that the CDMA and GSM versions have different batteries and they are not compatible, normally the GSM one is longer and black and the CDMA is wider and blue.

7079119237_9febda8fa3.jpg

Borrowed from Buddy Revell

Calibration

Once a month we´ll have to calibrate our battery so that the information to be shown on screen is accurate and true. The steps are as follows.
1. Charge the Nexus until the indicator shows us is 100%.
2. Disconnect it and let it discharge until it turns off by herself.
3. Then load up fully charged. Note that this state is reached after one hour approx. since it shows that is already loaded.

Note: There are several apps in the Market that help calibrate the battery, although I have heard that in ICS Google has changed the file location does. Log of our battery so many of them may not work well if they are not updated.
 
Last edited:

myrdog

Senior Member
Dec 8, 2010
56
9
London
Awesome. Those custom backlight levels are going to save a good amount of battery. I tried using a filter, but it made using the phone in sunlight impossible.

It's working inside well and based on what I see from the custom levels, it should have no issues once I take it outside.

As for the underclocking, comparing iOS and Android isn't fair. iOS has an advantage with its closed ecosystem. I personally overclock the GNex to achieve the same snappiness I had on my iPhone 4S. Sure the underclocking will save battery, but I might as well be using an older phone if I'm going to underclock.

When it comes down to it, everyone's battery is >50% screen consumption. Your custom levels are going to tremendously increase battery life.
 
  • Like
Reactions: hanifh

SrTapir

Senior Member
Jun 12, 2007
222
288
Barcelona
guiasapple.com
What rom is that? You should state that ...

It's in my signature, Liquidsmooth v1.25.

Awesome. Those custom backlight levels are going to save a good amount of battery. I tried using a filter, but it made using the phone in sunlight impossible.

It's working inside well and based on what I see from the custom levels, it should have no issues once I take it outside.

As for the underclocking, comparing iOS and Android isn't fair. iOS has an advantage with its closed ecosystem. I personally overclock the GNex to achieve the same snappiness I had on my iPhone 4S. Sure the underclocking will save battery, but I might as well be using an older phone if I'm going to underclock.

When it comes down to it, everyone's battery is >50% screen consumption. Your custom levels are going to tremendously increase battery life.

Thanks :)

With the iPhone comparison I just tried to emphasize that sometimes underclocking results in the same snappiest system, but yes, is a little unfair though :p (but I can assure that with the latest Kernels and ROMs that have been released, I have a totally fast and smooth system with only 1000Mhz).
 
  • Like
Reactions: gogol

zephiK

Inactive Recognized Developer
Aug 23, 2009
21,655
37,705
New York, NY
Good guide. Rather than seeing multiple thread's about awful battery life its nice to see people talk about how to maximize their battery life

Sent from my Galaxy Nexus using xda premium
 

BinkXDA

Senior Member
Mar 1, 2012
387
137
Good guide—thanks for taking the time to make it—but along with it’s very good parts, it has quite a few inaccuracies, is misleading in some places, doesn’t fully explain the ramification of making many of the changes that are proposed and makes questionable changes for very little gain. Amongst other things, my major issues with it are:
  1. You wrongly assume a device that does not get four hours of screen time is not optimized—this would be incorrect as one can get four hours of screen time with the stock ROM and default configuration.
  2. The stock ROM does not allow you to customize the backlight and CPU—so you should point this out.
  3. It’s condescending to the iPhone (while the GN might be better in many ways, patronizing another device has no place in a “guide”).
 
Last edited:
  • Like
Reactions: Cabal_

SrTapir

Senior Member
Jun 12, 2007
222
288
Barcelona
guiasapple.com
Good guide—thanks for taking the time to make it—but along with it’s very good parts, it has quite a few inaccuracies, is misleading in some places, doesn’t fully explain the ramification of making many of the changes that are proposed and makes questionable changes for very little gain. Amongst other things, my major issues with it are:
  1. You wrongly assume a device that does not get four hours of screen time is not optimized—this would be incorrect as one can get four hours of screen time with the stock ROM and default configuration.
  2. The stock ROM does not allow you to customize the backlight and CPU—so you should point this out.
  3. It’s condescending to the iPhone (while the GN might be better in many ways, patronizing another device has no place in a “guide”).

Thanks, but the guide tried to be a compilation of many procedures that would give you a longer batt life. Some of the recommendations give you maybe 4-5% more autonomy, some of them 0,5%, don't know because I'm not an engineer and don't have the tools and time to measure the actual rate of discharge of the device, I'm only a user that took some time in share his personal experience in the last 4 and a half months with the device.

1. It was a way of talking, did not tried to assume anything because was not thinking in anithing out of the people that are not having more that 3 hours batt time, was a simple way of selling something (a well/bad introduction depending on the eyes or mentality of the reader)
2. We are at XDA and this is a developer device, I asume a minimal technological base, I was assuming this. But I point this out because I also think that will help some people.
3. Tried to emphasize that while the over sold as an ultra-quick device is only 1Ghz Dual-Core, the GNex can be as fast and reliable as the iPhone 4S with the same speed, and also saving batt (and in addition you have 450 more Megaherzs if you want to use them.. if you root). It’s not condescending cause if I would have liked to buy an iPhone I would bought one as the 99% of the people here.

I am a simple user, as everyone here, trying to help people as people has helped me developing great ROMs and Kernels I like positive and concrete recommendations over vague and negative ones.
 

king23adrianc

Senior Member
hey op,

If we take in account that the Mega-Ultra-Cool-Fashion-Posh and "Ultra Quick" iPhone 4S has a only Dual Core 1Ghz processor, we can assume that with the same speed we can achieved a very good optimized and well balanced performance-battery friendly system.. and yes, with the last advances in kernels and ROMs, we can have a perfectly smooth system with a top speed of 1000Mhz.


i think the iphone is clocked at 800mhz even it has 1ghz
 
Last edited:

myrdog

Senior Member
Dec 8, 2010
56
9
London
First of all thanks to all the people for your comments!

I've updated the first post with your recommendations, and added a couple little things.

The Calibration section is a little confusing. It only takes 1 hour to go from 0% to 100%?

Also, do you know anything about calibration with ROMs that only allow you to charge to 99%?
 

SrTapir

Senior Member
Jun 12, 2007
222
288
Barcelona
guiasapple.com
The Calibration section is a little confusing. It only takes 1 hour to go from 0% to 100%?

Also, do you know anything about calibration with ROMs that only allow you to charge to 99%?

No, it takes 1 hour after the GNex indicates is fully charged. I'll try to change it in order to clarify.

No, sorry, maybe you can "delete battery logs" via recovery. (I never did it, and don't know if can be detrimental).
 

Top Liked Posts

  • There are no posts matching your filters.
  • 87
    This guide is not meant to be as a whole and is not meant to be followed from beginning to end. There are several recommendations based on my own experience, some of them will give you big battery savings, some of them minor ones; I tried to recopile every config that helps to save battery, but every config is not suitable for everyone. (I´ll point it at the beginning of every section in bold blue).

    You'll need a Rooted Galaxy Nexus, with a custom ROM and a custom Kernel.

    The custom ROM will give you the ability to make a deep configuration of the device in terms of options. I'm actually using Liquidsmooth v1.25, but AOKP, CM9 and SlimICS have the same options (if not more) than my actual.

    Some custom Kernels will give you the ability to change the CPU frequency and voltage, kernels are the main reason of some drainings or fantastic battery life, choose wise. :p

    The normal Galaxy Nexus battery life is about 4 hours screen time. If you are not achieving this, the main reasons could be:

    1. Some apps are draining your battery due to a continuous use (no deep sleep or continuous wake ups).
    2. Screen too bright.
    3. Bad kernels with draining problems.
    4. Weak signal connections.

    This guide is wrote by me, a simple user that is sharing his own experience of the last 4 and a half months with the device. Some statements may be wrong. I'll appreciate any positive recommendations in order to improve the guide and help the rest of the community to achieve the best battery life the device can give us.

    I'm using actually Liquidsmooth v1.25 and PopcornKernel, in a GSM GNex with standrad battery (1700mAh), and I'm getting this results:

    6929665280_40c34bfeff.jpg
    6929665324_46c999617b.jpg
    6929665376_2170980683.jpg
    7075740719_27631fed51.jpg


    SCREEN

    Due to the big screen, this is one of the elements of the device that affects in a major way to the battery live. (Great Savings)

    It has been checked that black themes have a great impact on the battery due to the fact that one black pixel does not consume any battery.

    Some apps have a black theme option on them, if you choose it you will save some battery.

    6929914768_16cc56ceb8.jpg
    7075991409_33bab942d6.jpg
    7075991915_f25d604d9f.jpg


    On the other hand the brightness is the other part in the screen that has a big impact on the battery. In a logic way, less the brightness more the battery life. (Greatest Savings)

    Now the latest ROM's have a new amazing feature, we can change the interval the sensor works to achieve the ambient light, reduce the brightness minimum value (that's by defect way too high in low light conditions), and customize your prefered light levels (that are too way too high in default configuration).

    By reducing the sample interval sensor a bit and reducing the minimum value a lot we can achieved abetter battery life in a great manner.

    7075992309_e6d4fb3a72.jpg
    6929915858_857881832b.jpg
    6929914864_3d26ee5092.jpg


    Also adjusting the light sensor levels to a more reliable one's that are by far lower than the default one's we'll achieved a more optimize system that consumes less battery.

    7095332465_3601a282b7.jpg
    7095332753_1c405b7e3d.jpg
    6949261896_cbbeee2aab.jpg


    Note: This are my actual, after 2 weeks of adjust, values but I'm still working on them, they are no 100% reliable.

    CPU

    The CPU is a great beast. In terms of battery is well adjusted, by as always, we can achieve a personal optimized system (this is Android, yeah!) that will balance performance and battery life. (Great Savings Underclock and Undervolt combo).

    A very good speed and fluidness can be achieved with a very good optimized and well balanced performance-battery friendly system.. and yes, with the last advances in kernels and ROMs, we can have a perfectly smooth system with a top speed of 1000Mhz.

    In the other hand Undervolt will help us to achieve a cooler system with some battery gain. With Undervolt we´ll limit the max. value of the Voltage for the specified frequency, if we have a kernel with Smartflex, this one we´ll allow lower voltages depending on the power need of the CPU.

    Two important things:
    1. It has been tested that the 700Mhz frequency is prefereable over the 300Mhz one, due to the drops on frequency signal of the phone.
    2. Undervolt values are not the same for everyone, it can oscillate depending on the individual CPU. When I UV I always test my system with an Stability Test app.


    6949261750_804a236691.jpg
    6929916566_0cdc76a98e.jpg


    Connections

    GNex is a phone...also.. well, it's a super computer with phone capabilities. Due to the "always connected" philosophy the optimal baseband will save a lot of battery. An optimal Baseband and Radio (region optimized) will require less power and time to connect to the antennas and will have better connection always (less power irradiated). (Medium savings).

    The Radio should be updated and region optimized, there's a magnificent post made by josteink that explains all the details concerning the Radios with links to every one available.(GSM)

    [Radio] (GSM) Galaxy Nexus I9250 Baseband dumps collection & discussion

    European Radio Recommended: XXKK6 (XXLA2 is giving too high "Phone Idle", resulting in drain problems)

    For the CDMA version there is another magnificent post by ready5 with a compilation of every RADIO for the CDMA version of the GNex.

    (CDMA) [RADIOS/HYBRIDS]*UPDATED* 4.0.4 FULL 2/6/2012 PLUS FRIED RADIO Halp!

    In the GSM version on the other part the 3G, HSPDA consumes great great great battery juice. If you are not in WIFI and are not using the data connection, a great way to save battery life is changing from HSPDA or 3G to 2G networks (this is really noticeable if you travel a lot by car or train, cause you are continuing connecting a reconnecting from different radio antennas).

    There's some ROMs as Liquidsmooth that allows when you are not on WIFI and after an specified delay, to change to 2G automatically (or low consuming) networks when you have the screen off. This is a great way to save battery when you are not at home, reducing the standby drain of the phone outdoors.

    6930022404_caffa3af3b.jpg
    .
    ibvnJPgSbMGp0v.gif

    The automatic 2G when sleep is a main function of Juice defender. Thanks to a1exus for recommendation.

    In the CDMA version the LTE consumes also great great great battery juice. If you are not in WIFI and are not using the data connection, a great way to save battery life is changing from LTE to 4G networks (this is really noticeable if you travel a lot by car or train, cause you are continuing connecting a reconnecting from different radio antennas).

    iURDNcSyxeYuq.gif

    Thanks to thenickisme for this!

    WIFI

    Wifi has a crazy history on the GNex. After talking and talking, posting and posting, it has been tested that WIFI always on while sleep is the best way to achieve a longer battery life. (Medium savings).

    iboaVtpFxNiwTU.gif


    Also the new ROM's have amazing feature that change the WIFI interval (we normally stay at the same WIFI always), increasing the value will save batterty life reducing the continues scans that produce the WIFI Always ON requirement.

    6929916302_0f560e0f47.jpg
    6929916820_e7d77ec545.jpg
    7075991537_7a40b48db3.jpg


    Services and Apps

    The best thing of Android is that we can configure anything, one of the best and underestimated feature is the Freeze or Service Uninstall. We did it before in Windows and we can do it now. Through the Apps section in Preferences or the mythic Titanium Backup we can disable or uninstall an internal function of the systems that is normally used, giving more resources to the system and in some cases, saving some battery. (Low to Minimum Savings).

    There are some ICS functions that no everyone uses. For example, I don't use any Bluetooth, NFC, Google Voice, Google Search or Speech function of the system, freezing or uninstalling them will optimize our system giving some battery juice.

    6929917548_ae837e78af.jpg
    7075993573_8b1e8d5f02.jpg


    Note: This is a dangerous thing if you don't understand what you're doing. Make always a Nandroid before Freezing or Uninstalling an essential function, just to be cautious.

    According to the Apps we have to take in account the Background Syncing or Sync Interval, most of the time the apps don't need to be synced every 5 minutes, like weather, if we make longer updates we'll achieve a good saving battery related. (Great Savings if many apps with many connections).

    6930263364_eb69f3503d.jpg
    6930263474_66a7c85bc3.jpg


    Widgets, 5 homescreens full of widgets updating in real time could be detrimental to the battery live, take care when adding widgets and as said in the previous paragraph, change every widget preferences to update in longer times than usually they have by default. (Great Savings if many apps with many connections).

    Bad Apps are the one's that not allow our device to deep sleep or wake up continuously our GNex. There are several on the market, Readability for example is a new one that wake up continuously our device attempting to download new articles, on the other part, some time ago Widgetlocker had some problems not letting deep sleep the GNexus (don't know now). (Great Savings if there is an apps giving deep sleep or wake ups problems).

    Pointing on this, the best way to know if any app is not behaving well in the system is through 2 apps:

    - BetterBatteryStats, that will look for any wake up of the device while sleep.
    - CPU Spy, that will tell us if the device is deep sleeping ok or not.

    Other things

    There are other things that will help us in a great or minor manner to save battery life.

    Sync Data usage (Google services like contacts, bookmarks, etc..) consumes battery, if you limit this usage, you´ll gain some juice. The new ROM's in the Powersaver tag will allow you to limit this sync usage. (Low Savings).

    7075991627_34b6c93b3c.jpg
    7075992659_992e1651d9.jpg


    The Dial Pad Touch Tones and Vibration affects battery also (yepp it's true, and in a great way!), disabling this features will give you some extra battery juice. (Low to Medium Savings with combo sound plus vibration).

    6929916948_4013378d14.jpg


    The Google Location services and Backup&Reset Data consumes great battery also, limiting this services will gave you some extra juice. (Medium Savings).

    6929917048_af1c4d9527.jpg
    7075993311_4d5b1f4c3e.jpg


    The last little thing that will help you save batt life will be the Automatic Date&Time option, disabling it will give you some extra juice also. (Lowest Savings, practical minimum).

    6929917290_7fe93e36b9.jpg


    Live Wallpapers, they are very nice but will drain your battery quickly. Static Wallpapers are preferred, and if posible, dark ones. (Medium to Great Savings).

    Experimental

    This are new tweaks that normally appear in new/advanced kernels, his use according to battery save is still not really tested or can have a detrimental on the physical conditions of the device/battery. Use them with caution or if you really know what you are doing.

    [MOD][KERNEL]Battery Life eXtender (BLX), this is a tweak created by the popular Ezekeel and in his owns words: "Older types of rechargable batteries exhibited a 'memory effect' which made it neccessary to completely charge/discharge the battery when using to prevent degradation of the capacity. Modern Lithium-Ion batteries like in the Nexus S do not show this problem and thus it is not necessary to use the battery in complete (dis)charge cycles. In fact on the contrary, it is commonly accepted that both very low and very high charge states accelerate the degradation of the battery capacity (that is why you should store Li-Ion batteries at around 40% charge).

    While a low charge state can be simply avoided by charging the device more often, the battery in the Nexus S by default is charged to around 95% capacity and I could not find any app or tweak to stop the charging at a lower capacity. Thus the only way was to use the manual override and pull the cable which is annoying since one had to monitor the charge state."
    (Unknown Savings).

    Galaxy Nexus is charged by default to the 96% of this capacity, with this new tweak you can gain this 4% (don't know for sure if you can get the 101%) of battery life, in 4 hours screen time, more or less 10 minutes, but it can be detrimental on the long way to the battery physical life.

    You can found this tweak in the last nightly of Franco's Kernel, and can be activated via his own app.

    6934120678_4987c66b12.jpg
    6934079422_3365b0af5d.jpg


    You can find more information in Ezekeel post here at XDA.

    [MOD][KERNEL]Undervolt of IVA and CORE Voltage, new patches let undervolt the IVA (hardware media decoder) and CORE (GPU Voltage), I'vce been playing with this all the day and I've managed to undervolt a 15-20% de original frequencies. (Unknown Savings).

    I understand that with this we are limiting the maximum voltage they can use, letting them to use lower ones according to GPU load. I'm not sure at this (GPU uses smartflex also ¿?) but with a descent of 20% on the voltage could result in longer battery life while playing games or seeing movies.

    I'll try further undervolts, but this are my actuals on a stable system.

    6949261248_e706bf914d.jpg
    7095332909_143ebafa90.jpg


    You can play with this voltages via the last nightly of Franco's Kernel, and via his own app.

    Take care playing with this, could result in system instabilities, reboots, freezes, etc.
    29
    Links of interest

    - BetterBatteryStats, A high battery drain is often a limiting factor for a great user experience.
    With BetterBatteryStats you can analyse the behavior of your phone, find applications causing the phone to drain battery while it is supposed to be asleep and measure the effect of corrective action.

    - CPU Spy, This is a simple app to display the time the CPU spends in each frequency state. This can be a useful tool in diagnosing battery problems or tweaking your over-clock settings.
    It also displays the current kernel information.

    - StabilityTest, StabilityTest is a stress-testing tool for android devices with error reporting.
    StabilityTest is a CPU, GPU, RAM/memory stress-testing tool for your device, whether stock and unrooted (limited functionality) or rooted and overclocked with SetCPU, SetVsel or similar tools.


    Extended Battery

    At the end, the best way to extend the battery life is with an Extended Battery, they are not very expensive and only increase a little bit the thickness of the device. They can be bought at several places through the typical places as Ebay, Expansys or Amazon.

    Important: Take in account that the CDMA and GSM versions have different batteries and they are not compatible, normally the GSM one is longer and black and the CDMA is wider and blue.

    7079119237_9febda8fa3.jpg

    Borrowed from Buddy Revell

    Calibration

    Once a month we´ll have to calibrate our battery so that the information to be shown on screen is accurate and true. The steps are as follows.
    1. Charge the Nexus until the indicator shows us is 100%.
    2. Disconnect it and let it discharge until it turns off by herself.
    3. Then load up fully charged. Note that this state is reached after one hour approx. since it shows that is already loaded.

    Note: There are several apps in the Market that help calibrate the battery, although I have heard that in ICS Google has changed the file location does. Log of our battery so many of them may not work well if they are not updated.
    3
    i m getting screen time of 6.30 hours and stand by -16 to 17 hrs :good:

    Must be tiring to lug that car battery around with you all the time, huh?
    2
    ?????

    I am a bit confused about your results. You seem to get roughly 15 hours out of your GNex with all your battery saving tips. I have a Brand new Nexus, Stock Jellybean Stock 1750mAh Batt, and get about 1 day 10 hours on 3G with 15min updating emails - 1hr facebook - 2hr weather with medium use. I never use Wifi when i surf the web/sunc as my HSDPA is unlimited, faster and superior.

    I was expecting 2 days of battery life out of this post. And what is that app in your results thats draining all your battery? some kind of game?

    I will take pictures of my next discharge and post.
    1
    Wanted to say thanks for this thread, saved me a ton of battery. Was having issues getting through a day on my 2000mAh battery, no issues now. I can almost go a full 2 days on a charge with a couple hours on the phone and screen on of about 3 hours.

    Thank you!