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How to find battery consuming part in application

I have a hybrid android application which using different features like vibration, WIFI,bluetooth etc. Recently i have made changes into WIFI locks which i need to keep available event phone goes into sleep mode as i want to do a streaming in background as well.
Currently i am facing a problem as phone battery started drain very quickly. I want to figure out how i can find out which part of application is very so long or taking too much CPU. I have tried DDMS tool to and use method profiling but result not showing anything interested here. I also tried battery historian but have no clue why my application consuming battery very quickly. Can someone tell me is there any other tool which i can used to figure out this problem?

How to detect which thing is causing battery drain in my android app?

Recently I have developed an android app . The app is ok . But the user is complaining that app causing battery drain . Even some battery optimizer app (Like Battery Doctor) suggesting my app to force stop as it is causing battery draining too fast . There are a lot of service (like sync service , socket service) and broadcast receiver is used in this app and alarm manager is used in the app. How can I detect actually which is responsible for battery draining ?

I addressed the major contributors to battery drain in another of my posts.
If I understand correctly, you want to identify which section of code (including libraries) of your app is the culprit.
Here's my suggestion:
Confirm that there is a problem: Get as identical a phone configuration as possible, say by having the user send a dump of all processes running on their phone, and confirm there is a problem.
Confirm that it's your app: run tests with your app running and without. Make sure you take several measurements.
(A) If you have a profiler, use it to profile your application and identify potential issues. (B) If you don't have a profiler, create some dummy input, and start exercising your app while cutting out different functionality. Measure the battery drain.
NOTE: If the drain is small, detection becomes an issue. It's the old signal to noise ratio thing. The smaller the drain, the more measurements you have to take to determine what it is. Of course, the smaller the drain, the less of an issue it is.

Android app not listed in Battery Usage

I was given a question and I have a hard time finding the correct answer.
Let's say that I have an app called MyApp and when this app is installed it drains the battery life really fast, I know that because when I uninstall the app the battery life is significantly improved.
When the app is installed I can't see it in the Android Build-in Battery Usage Stats in settings app which means that it's not the app that's draining the battery life.
What could be the problem?
I thought that the problem is that maybe the app is activating background services of Android, but was told that when I activate a service from an app, it is registered under the app's name and it should be listed in the battery usage.
I can't seem to find any information describing the problem I was given.
Any ideas guys?

Explicitly Managing WiFi Power Consumption in Android

Background
I'm developing a research application that runs on Android phones. In short, the application runs so long as the phone is on and periodically takes information from many components and sensors on the phone. The application is to disturb the user as little as possible. That being said, it's draining the battery far too quickly and forces the user to recharge every day. This simply won't do.
To try and figure out how to improve the situation, a colleague also working on the application let the application run for a long period of time and noticed that the biggest battery hog is WiFi. My current idea is to manually shut off WiFi when it's not in use in an attempt to save power. AFAIK, Android uses PSM for WiFi to accomplish this to some end, but it doesn't seem to be enough.
Problem
Is there a way to "ramp up" Android's PSM? Or, if there is not as this question suggests, is there any way that I can safely turn WiFi on and off without adversely affecting the user? I.e., is there a way to tell which applications are using WiFi and turn it off when none are? Do standard applications - such as the web browser and email clients - use WiFi locks to prevent WiFi from being turned off when they are working?
Any advice on where to start in solving this problem are greatly appreciated. Information on how Android's PSM works, how long it takes for it to take effect, or any information relevant to the problem are very welcome.
Thanks for your time!

Is there a way to "ramp up" Android's PSM?
Not via the Android SDK.
I.e., is there a way to tell which applications are using WiFi and turn it off when none are?
The OS does this already.
Do standard applications - such as the web browser and email clients - use WiFi locks to prevent WiFi from being turned off when they are working?
Some probably do. You are welcome to search the Android source code and find out. Of course, bear in mind that there are no "standard applications" -- I presume you are thinking of the ones that are part of the Android open source project.
Any advice on where to start in solving this problem are greatly appreciated.
Find out where in your own code you are being inefficient, specifically here:
the application runs so long as the phone is on and periodically takes information from many components and sensors on the phone.
If the device behaves fine when your code is not running, and the device does not behave fine when your code is running, then the problem lies in your code. Conversely, if the device does not behave fine even when your code is not running, then something else is afoot (device defect, firmware defect, rogue application, etc.), but it probably has nothing to do with StackOverflow.

How to stop an android device from being charged programmatically?

Is there an Android API for stop charging even though physically the charging is on?

Reading previous answers, it looks like there's no way to do this exclusively in software. However, it should be relatively easy to do it with a little hardware help - i.e. by using any Bluetooth- or WiFi-enabled smart electrical switch with open API. The phone could then switch the charger on or off programmatically whenever it feels like it.

Is there an Android API for stop charging even though physically the charging is on?
AFAIK no.
Justification:
android.intent.action.BATTERY_CHANGED is a protected intent that can only be sent by the system. Therefore you cannot duplicate or override the functionality.

You guys are all missing the point - the purpose of limiting charging is to increase battery lifespan by keeping it away from fully charged conditions (and near empty but that's a different issue). If you anticipate needing a full charge then tell it to charge to 100.
If you can't set a charge limit then the battery would rarely be idle and ideally charged when on the charger. It probably requires device level support though.

https://play.google.com/store/apps/details?id=es.guille.stopcharge uses echo "0" > /sys/class/power_supply/battery/device/charge. It works for me on a nexus 4 (rooted), as long as the device isn't fully charged (in a charging state).
Also relevant: https://android.stackexchange.com/questions/15001/how-can-i-avoid-the-battery-charging-when-connected-via-usb

Contrary to some answers indicating it's not possible, it is, indeed possible with ROOT. You can find some apps on the Play Store that will allow you to do this (with root permission, of course).
The best app that works on every phone I've tried it on is Battery Charge Limit. You can download it from the Play Store or the XDA discussion thread. The app is under active development so, if you find that your phone isn't supported, just submit an issue on its GitHub page.
NB: I am not the developer of this application.

This is unfortunately not possible. Android only have read APIs for battery data.
Battery charging control is internal to the Android kernel and battery IC modules. Manufacturers do change it from time to time, like HTC is having small cycles from 95-100% (a bad idea IMO), Samsung does stop charges as soon as it reaches 100%, but I've never seen a device able to stop charging before 100% to reduce battery aging :(.
At best if we're lucky, a sysfs interface might help do that, but it requires root and will differ from device to device.

Just to add to this. Samsung phones do not stop charging after 100%. As far as I'm aware they "trickle" charge past this point however they recommend you do not charge your phone past 100% for over 1 hour. Battery manufacturers like Anker also state the same so the idea of stopping the charge at 100% would be really useful. The risks of leaving the phone on charge are battery bloat and eventually cell rupture. I wasn't aware of this to start off with an killed my samsung battery within 3 months of owning the phone.
To expand on the original question. I've noticed some kernels allow fast charging. If they are able to alter the charge rate up could we alter the charge rate down (trickle) to meet a desired finish time (when your morning alarm goes off)??

I have installed a timer on the AC receptacle where I plug my Moto E's charger into. After guestimating how much time the battery needs to charge to about 85%, I set the timer. This is not my idea of a solution, but at least it keeps my phone from being charged to 100%, as I usually err on the short side when setting the timer.

I dont think there would be such an api. If it does exist it needs to be supported by the device manufacture as its not a pure OS lever feature. The same reason would make it a bad idea to use it as not all devices will support it.
That being said it would be a bad idea to use/implement it , mobile devices are not built to directly run from the power supply and a user will not plug in the cable if he/she did not want to actually charge the device.