Battery logger inspired by James Davenport's, written using AWK. The recorded data is visualized using D3.js.

It logs information about the state of your battery pulled from ioreg and stores it into a CSV file. In particular, the current version stores the following data on each invocation:

• Date (UTC)
• Cycle Count
• Design Capacity
• Max Capacity
• Current Capacity
• External Connected

Scheduled Monitoring with crontab

For regular monitoring, you might set it up using a crontab, which you could edit as follows:

$ crontab -e

and enter this:

* * * * * /path/to/your/repo/log-battery.sh

Scheduled Monitoring with launchd

If you prefer launchd (which Apple would prefer that you use), you could make a file like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.codiform.OSXBatteryLogger</string>
    <key>ProgramArguments</key>
    <array>
        <string>/path/to/repo/log-battery.sh</string>
    </array>
    <key>StartInterval</key>
    <integer>60</integer>
    <key>WorkingDirectory</key>
    <string>/path/to/repo/osx-battery-logger</string>
</dict>
</plist>

Then save it in ~/Library/LaunchAgents/com.codiform.OSXBatteryLogger.plist and run:

$ launchctl load ~/Library/LaunchAgents
$ launchctl start com.codiform.OSXBatteryLogger

For more about launchd and tools to help you manage it, I recommend Nathan Grigg's introduction and the launch man page.

Header

A header for the CSV file is needed such that D3.js. If you create a new file, make sure that the following line is included:

Date (UTC),Cycle Count,Design Capacity,Max Capacity,Current Capacity,External Connected