1: The Battery Meter Isn’t Entirely Accurate.
Perhaps you’ve noticed this in other devices: Battery meters are rarely very accurate. One minute you could have 40 percent left on your battery, and the next minute you’ll see that percentage cut in half. This isn’t entirely the fault of hardware and software manufacturers, but they could at least come out with a warning. Laptops tend to have this issue the most; since they suck the juice out of the battery quicker, the effect is more obvious. The rate at which a battery drops in charge depends on its chemistry. In most lithium-ion (Li-Ion) batteries, the charge falls more rapidly as the battery loses voltage. So, when your battery meter reads below 50 percent, all bets are off.
2: Windows’ Battery Replacement Notifications Aren’t Always Accurate, Either
In the latest iterations of Windows, you get a notification when Windows recommends that you go out and get a new battery. The problem is that this notification isn’t always realistic. Your battery can still have tons of juice left in it and Windows will just pop up and tell you to go dump some cash on a new battery you don’t need. Again, this isn’t entirely the fault of Windows or your hardware. It’s just that batteries can do some very spooky stuff sometimes. Remember, it’s just a container with chemicals in it, not something that can be super-accurately measured. So, now that you are aware of these two things…
What to Do About Inaccurate Battery Replacement Notifications
Calibrate the battery. This involves charging it and discharging it while using your laptop in a precise manner that will make Windows detect how much charge the battery really has left (in terms of Watt hours). To do this:
Fully charge your laptop battery then leave it plugged in for a few hours. Use the laptop lightly, avoiding things like games or any other applications that overwhelm your hardware. This allows the battery to shave off the excess heat from the charging phase. Go to the “Start menu -> Control Panel -> Hardware and Sound -> Power Options -> Edit Plan Settings -> Change advanced power settings”. Once in the advanced settings dialog, scroll down to “Battery” and expand it (click the plus sign next to it). Expand “Critical battery action.” Select “Hibernate” under “On battery.” Expand “Critical battery level” and change both options to “5%.”
Remove the power cable from your computer and allow it to drain the battery normally until it shuts off. After this is done, just leave it alone for about six hours. Charge the laptop fully again.
If you still get a battery replacement message when clicking the battery icon on your task bar, it really is time to get a new battery. This procedure at least will not only make Windows give you replacement recommendations at the right time, but it will also get it to display your laptop’s remaining battery power more accurately. Your mileage may vary for reasons stated above, though.
Still Got Windows Battery Issues?
If you still have questions about how battery power is measured and what you can do to optimize it, leave your question in a comment below. There are thousands of different laptop models out there and the information out there is very limited, so don’t feel ashamed to ask a question when you have no clue what your laptop is doing.
