How do I change the battery charging threshold on my laptop?
Answer: Laptops are portable machines and therefore most people run their laptops off battery power more often than AC power. That means the laptop battery must be charged on a regular basis. But repeatedly charging the battery can reduce the overall life of that battery. Therefore, some computers allow you to set a "charging threshold" that will only charge the battery once it falls below a certain level.
By default, most laptops charge the battery when the charge falls below 95% or 96%. Therefore, if you leave your laptop plugged in to a power source and don't use it for several days, it may initiate a charge several times to top off the battery at 100%. If you set the charging threshold to something lower, like 80% for example, the laptop would initiate the recharge less often, potentially prolonging the life of your battery.
Setting the battery charging threshold
Since manually setting the battery charging threshold is a rather advanced option, there is no way to configure this setting on many laptops. Your ability to set the charging threshold is actually dependent on the hardware, since the charging is controlled by a hardware component. If your computer supports custom battery charging settings, you can modify the threshold using a control panel or software utility. For example, some Lenovo laptops include a "Power Manager" utility that allows you to change the charging threshold. Sony VAIO machines often include a "VAIO Control Center" that allows you to do the same thing.
If you use Windows and your computer does not have a custom battery management tool, there is no way to modify the battery charging threshold. If you use a Mac, there is also no way to override the default settings. While this may seem like bad news, the good news is that modern batteries last much longer than laptop batteries from only a few years ago. Therefore, custom charging settings are not as important and may have little effect on the life of your battery.