I first wrote about this utility a few years ago, and with the imminent arrival of Windows 8, I figured it was time for another look.
Much as Windows' power-management capabilities have improved over the years, the OS still doesn't tell you much about your battery.
In fact, from what I can see of Windows 8, Microsoft hasn't changed anything about battery status reporting.
That's why I continue to be a huge fan of BatteryBar, a superb power gauge that's compatible with XP, Vista, and Windows 7. (Presumably the developer will add Windows 8 support as well when the time comes. Alas, Microsoft didn't follow my advice and build BatterBar right into the OS.)
Normally, if you want Windows' read on how much battery life is left, you have to mouse over the tiny System Tray power icon. BatteryBar adds a full-time, at-a-glance gauge to the right side of the taskbar, which I find incredibly handy.
That gauge shows you either a percentage of battery life remaining or the amount of runtime left; clicking it toggles between the two readings. Interestingly, when you're running on AC power, the gauge switches from green to blue and shows how long until you reach a full charge.
But wait, there's more: when you mouse over the gauge, a pop-up window displays a boatload of additional information, such as total battery capacity, charge/discharge rate, AC status, and even a lifetime estimate based on historical charge/discharge data. That's what I'm talking about!
Although BatteryBar is free, there's also a Pro version that adds more features, like a graph of battery profiles, low/critical power warnings, and automatic power-scheme switching that kicks in when you switch between AC and battery power. A lifetime license costs a mere $5 -- well worth it, in my humble opinion.
That said, I suspect most users will be happy enough with the free version.
Whatever version you decide on, don't run a laptop without BatteryBar. Seriously.
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