How to measure health of your Windows 7 Laptop Battery

Windows 7 have many hidden
features and commands in it and
you are unaware of most of them.
There is a little trick available in
Windows 7 by which you can
measure the health of your Laptop’s
battery. To Perform this task, you
are required to plugin your laptop.
This is necessary to check the
battery life as after some time the
lithium Ion battery will start dying
and stops charging full. Thus,
performance of laptop battery starts
degrading. The power backup will
go down from few hours to few
minutes. We can know about
remaining charge time of battery
but to know about the health status
of battery you have follow certain
steps and commands.
There is a command in Windows
Command Processor, powercfg
with a parameter using which you
can easily check the status of your
laptop battery health. Here are the
steps to use this command:
Click Start button and type cmd
in search box.
Right click on it and run cmd as
an Administrator.
Type powercfg –energy in the
command prompt and press
enter.
System will enable a trace for 60
seconds. For these 60 seconds,
the windows would completely
observe and analyze the
performance of the system and
provide the output.
After 60 seconds a report is
prepared which shows errors,
warnings etc. The report will be
generated as a HTML file by
default in the system drive
where your OS is installed.
To see the system report go to
directory and open the file.
There will be lot of information in
that file. So, just scroll down until
you see Battery Information
section.
Battery Information section
provides the information of
battery type, capacity, last full
charge which is the maximum
potential of your battery.
To calculate the percentage of
present charging capacity we
perform a last Last full charge
divided by Design capacity of
the battery multiplied by 100
which gives you the percentage
of usage.
Using these steps you can now
easily find out how the battery
performance has degraded over a
period of time and can guess when
is the right time to replace your
battery.