### Sample script to check Battery Health 
### on systems with a single battery 
### Compatible with Windows 7 and later 
### This script is provided As Is 
### Script by Joao Botto 
### Version 0.3 
### Execute this script when you want information 
### about the battery health 
### or regularly as a scheduled task 
### show - Shows current battery health on screen 
### reg - Save information in HKLM:\SOFTWARE\BatteryHealth 
### file - Save information in c:\BatteryHealth 
# Compute battery health in percentage 
# of original possible cycles 
Function Test-BatteryHealth 
    $fullchargecapacity = (Get-WmiObject -Class "BatteryFullChargedCapacity" -Namespace "ROOT\WMI").FullChargedCapacity 
    $designcapacity = (Get-WmiObject -Class "BatteryStaticData" -Namespace "ROOT\WMI").DesignedCapacity 
    if ($fullchargecapacity -eq $designcapacity) { 
        Write-Host "Your system doesn't seem capable of providing accurate battery information`n" -ForegroundColor black -BackgroundColor red 
        Exit 1 
    $batteryhealth = ($fullchargecapacity / $designcapacity* 100 
    if ($batteryhealth -gt 100) {$batteryhealth = 100} 
    return [decimal]::round($batteryhealth)  
# Show battery health on the screen 
Function Show-BatteryHealth 
    if ($batteryhealth -gt 90) { Write-Host "Last full charge was $batteryhealth% of original capacity`n" -ForegroundColor black -BackgroundColor Green } 
    if ($batteryhealth -lt 89 -and $batteryhealth -gt 70) { Write-Host "Last full charge was $batteryhealth% of original capacity`n" -ForegroundColor black -BackgroundColor Yellow } 
    if ($batteryhealth -lt 69) { Write-Host "Last full charge was $batteryhealth% of original capacity`n" -ForegroundColor black -BackgroundColor Red } 
# Write battery health and date 
# to the registry 
Function Add-BatteryRegistry 
    If (!(Test-Path HKLM:\SOFTWARE\BatteryHealth)) { 
        If (!([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")) { 
            Write-Host "Cannot write to registry. This script needs to be run as Administrator`n" -ForegroundColor black -BackgroundColor red 
            Exit 1 
        $null = New-Item -Path HKLM:\SOFTWARE\BatteryHealth 
    Set-ItemProperty -Path HKLM:\SOFTWARE\BatteryHealth -Name EvalDate -Value $date 
    Set-ItemProperty -Path HKLM:\SOFTWARE\BatteryHealth -Name PercentOrigCapacity -Value $batteryhealth 
# Write battery health and date 
# to a file 
Function Add-BatteryFile 
    if (!(Test-Path c:\BatteryHealth)) { 
        $null = New-Item c:\BatteryHealth -type directory 
    Add-Content c:\BatteryHealth\Log.txt "`n Assessed on $date" 
    Add-Content c:\BatteryHealth\Log.txt "`n On the last full charge the battery could hold -- $batteryhealth% -- of its original capacity" 
    Add-Content c:\BatteryHealth\Log.txt "`n" 
# Main 
$date = Get-Date -format d 
$batteryhealth = Test-BatteryHealth 
switch ($action) { 
    "show" {Show-BatteryHealth} 
    "reg" {Add-BatteryRegistry} 
    "file" {Add-BatteryFile} 
    "?" {Write-Host "`n" 
         Write-Host "Available parameters:" 
         Write-Host "show - Shows current battery health on screen" 
         Write-Host "reg - Save information in HKLM:\SOFTWARE\BatteryHealth" 
         Write-Host "file - Save information in c:\BatteryHealth" 
         Write-Host "`n" 
    default { 
        $wshell = New-Object -ComObject Wscript.Shell 
        $continue = $wshell.Popup("You haven't provided a parameter such as show, reg or file. `n`nPress OK to continue and log battery capacity information to file and registry",0,"No Parameter",0x1)  
            if($continue -ne 1) {Exit 1} 
# end 
Exit 0


Have you ever thought that you needed to buy a new battery for your laptop?


And was it really a case of the battery not holding the desired capacity anymore, or was it a case where your new power settings or work habits were consuming the battery faster?


How do you even know if your battery is still healthy?


This is a sample script that collects information about the capacity achieved on the last full charge, and compares it to the design capacity specified by the manufacturer.


The script outputs the percentage of capacity that your battery can still hold, so that you know whether it's time to buy a new battery or change your power settings.

It also has the ability to store the capacity information in a file or registry, so that you can later collect that information through System Center Configuration Manager and report on the battery state of all devices in the organization.


Just pass one of these parameters when running the script:

show - displays battery health on your screen

reg - saves information in HKLM:\Software\BatteryHealth

file - saves information in C:\BatteryHealth


Known issues:

- doesn't work on devices that have multiple batteries

- doesn't work on some HP devices


Also, please note that this script is reading information from the firmware, and therefore the measurements are only as accurate as what the firmware is reporting