Microsoft

Check out the health of your device with the Windows 8 Battery Report

A new feature in Windows 8 will produce a detailed report on your system's battery usage.

If you are using Windows 8 on a laptop or Windows RT on a tablet, you'll be interested to know that Windows 8 has a new feature that allows the operating system to produce a detailed report on the system's battery usage. This new feature can come in handy as a troubleshooting tool when you are encountering problems with your battery maintaining a charge or as a general information tool if you just want to keep tabs on your battery usage. The Battery Report is generated by Windows 8's Power Configuration Utility, which you run from the command line with a special switch.

In this edition of the Windows Desktop Report, I'll take a look at Windows 8's Battery Report.

This blog post is also available as a TechRepublic Screenshot Gallery.

Getting started

Launching the Power Configuration Utility and running the Battery Report is easy, once you know how. To begin, use the [Windows] + Q keystroke to access the Search Apps page. Then, type cmd in the text box and click Command Prompt, as shown in Figure A.

Figure A

Accessing the Command Prompt from the Start screen is easy

In a moment, you'll see the Command Prompt window appear. Type the following command and press [Enter].

powercfg /batteryreport

When you do, the Power Configuration Utility immediately compiles the report and displays a message to that effect, as shown in Figure B.

Figure B

It only takes a moment for the Power Configuration Utility to compile the Battery Report.

Now, launch File Explorer, navigate to the specified folder, locate the battery-report.html file, and double click it. When the Battery Report page loads in your browser, you'll have to scroll down to see the entire report. As you'll see, the report contains six sections plus the header. To make it easier to look at the report in this article, I have divided my screen shot of the report down into seven images corresponding to each of the sections. Let's take a closer look.

Header

At the top of the report, as shown in Figure C, is some general information about the computer that includes the name assigned to the system, the brand and model of the device, the BIOS version and date, and the operating system build number. It will then list an item called Platform Role, which as you can see is identified as Mobile for this laptop. The next item in this section is called Connected Standby and you can see that for this particular laptop it is listed as Not Supported. This is followed by the date and time that the report was run.

Figure C

At the top of the report you'll find some general information about the computer.

When you run the Battery Report on a Surface RT or similar device, you'll see that the Platform Role is listed as a Slate. You'll also see that Connected Standby is listed as Supported.

One of the big benefits ARM-based devices is that they can last days or weeks on a single battery charge. When Microsoft was creating Windows RT they wanted it to have the best possible battery usage for a WOA (Windows On ARM) and developed a new power mode technology called Connected Standby.

Essentially, Connected Standby allows a Windows RT device to conserve battery power by entering a very low power mode when the device is not in use, but remain connected to the network. The goal is to allow the system to conserve battery power while still allowing a Live Tile on the Start Screen to maintain connectivity to its source. For example, a news or weather app can maintain its connection such that when you wake up a Windows RT device, the information displayed in the Live Tile will be as current as if the system was always on.

Installed batteries

In the Installed batteries section, shown in Figure D, you'll find detailed information about the battery including the name, serial number, and manufacturer. While the particular battery shown in this screen shot doesn't list the name or serial number, many actually do.

Figure D

In the Installed batteries section, you'll find detailed information about the battery.

The Chemistry is listed as LION which indicates that this is a Lithium Ion battery. As you can see, the next item in this section is Design Capacity and represents the amount of a charge that the battery was designed to hold. The value is represented as mWh, which stands for milliwatt hours. (Laptop batteries have a voltage rating (V) and milli-Amp hours (mAH) rating and these two ratings are multiplied together to come up with the milliwatt hours capacity.)

The next item is called Full charge capacity and represents the amount of charge that the battery will actually hold. As you can see, in the case of my example system, the full charge capacity is actually larger than the design capacity. I suppose that this has something to do with this being a brand new system. However, on most of the battery reports that I have seen so far, both the design capacity and the full charge capacity have been equal or the full charge capacity has been less than the design capacity.

The last item in this section is called Cycle count and this value indicates the number of times that the battery has used up 100% of its charge. For example, a cycle could be measured each time that the battery has run all the way down and then been recharged. A cycle could also be the result of discharging to 50%, charging to full, then discharging to 50% again. Batteries have a limited amount of cycles to work through before they are considered consumed. Maximum cycle count varies depending on a number of factors, but the battery manufacturer will have a maximum count value listed in the battery's specifications.

Recent usage

In the Recent usage section, shown in Figure E, you'll find a table that lists the power states - Active or Suspended - which the system has gone through over the last 72 hours. As you can see, the table indicates the time that the system started, whether the power source was the battery or AC, as well as the remaining capacity of the battery at the time the entry was made. As you can see, the remaining capacity is shown as a percent as well as the mWh.

Figure E

The Recent usage section, you'll find a table that lists the various power states from the last 72 hours of use.

Battery usage

The Battery usage section features a chart as well as a table that will indicate the date and time for each instance when the battery was drained over the last 72 hours. As you can see in Figure F, after five and half hours of use on April 15, the battery on this laptop was drained 95% and that equated to 52,012 mWh being used.

Figure F

The Battery usage section features a chart.

Usage history

In the Usage history section, shown in Figure G, you'll find a table the shows the history of system usage on both AC and battery power.

Figure G

The Usage history section shows the history of system usage on both AC and battery power.

Battery capacity history

In the Battery capacity history section, shown in Figure H, you'll find the charge capacity history of the system's battery. As you can see, this table shows both the full charge capacity and the design capacity, thus providing you with a way to keep an eye on the health of your battery. For example, if you notice that over time, your battery doesn't hold its charge, this table could reveal that your battery is no longer charging to its full capacity. Again, this example chart is probably skewed because this is a brand new laptop.

Figure H

In the Battery capacity history section you'll find the charge capacity history of the system's battery.

Battery life estimates

At the end of the report is the Battery life estimates section, shown in Figure I. In this section, you'll see a table that will indicate how long you can expect the battery to last at a full charge capacity and at design capacity. These estimates are based on the observed drains. This too will provide you with a good indication of the health of your battery.

Figure I

The Battery life estimates section will indicate how long you can expect the battery to last.

What's your take?

Are you running Windows 8/RT on a laptop or table? Have you run the Battery Report? As always, if you have comments or information to share about this topic, please take a moment to drop by the TechRepublic Community Forums and let us hear from you.

Also read:

About

Greg Shultz is a freelance Technical Writer. Previously, he has worked as Documentation Specialist in the software industry, a Technical Support Specialist in educational industry, and a Technical Journalist in the computer publishing industry.

7 comments
dcoffing
dcoffing

I have the ThinkPad2 that I upgraded to Windows 8.1 and noticed my battery life which had been pretty decent just drop off considerably even though it was in "standby". I ran  powercfg /? to see all the available options and noticed there was another option /sleepstudy. I ran it in Command Prompt (Admin) and the report showed high Connected Standby battery drains. It has a really useful section called Top 5 Offenders and it listed the culprit to be my Sierra Wireless 4G LTE - AT&T being active 100%. The ThinkPad2 came with an installed  AT&T sim card and they are hoping to get you as a Mobile Broadband customer which I won't be because I use my smartphone and tether for my data.  I actually had the 4G LTE Broadband turned off in my wireless settings. Apparently it is still doing something because the SleepStudy report caught it. I am now right clicking and DISABLED the Mobile Broadband network connection to see if that will fix my battery drain issue.

dennis
dennis

It would be nice to have this with a desktop connected to an APC or other brand of USB-connected backup battery

bmwbiker
bmwbiker

Very useful. Good work, Greg. Would it be possible to create a script that would with one click bring up the report in your browser? I wish I had time to work on this.

sarai1313
sarai1313

one more tool to add to the box. thanks

Mark W. Kaelin
Mark W. Kaelin

What does the Windows 8 Battery Report tell you about your devices battery? Is it time to get a new battery?

Greg Shultz
Greg Shultz

...a simple batch file to do the trick. Just create a text file on your desktop containing the commands powercfg /batteryreport battery-report.html and save it as BatteryReport.bat. When you run it, the Power Configuration Utility will create the report and save it on your desktop. Then, your browser will immediately launch and display the battery report.

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