Linx Window 10 Tablet

Thanks for the reply. I will have to think about that. That description, however, is not entirely accurate. There is a battery icon on the task bar that indicates the status of the battery. When you click on the battery icon, a small window opens up that gives a larger display of the status of the battery. There is also a slider in the window which you can slide along to the right or left. To the right it is set to “Best performance,” to the left it is set to “Best battery life”. So Windows does have a built-in feature for controlling the status of the battery (screenshot attached). But it doesn't seem to control directly this particular feature that I am now talking about. The screenshot currently shows the battery plugged in and fully charged at 100%. If I leave it plugged in like that for several days, the charge status drops to 99%, then a few days later it drops to 98%, and continues to drop over time as long as it remains plugged in. The lowest I have seen it go is 87%. But it takes quite a while to get there, while it is plugged in. I would like to be able to set that limit manually somehow, if that is possible.

You are right there is a slider for performance how the device acts when connected to ac or running on battery. But the method of control is with processor frequency, gpu frequency & how often the screen refreshed as well dimming the screen back light. More control over selectively suspend manageable devices like usb, serial adapters, wireless adapter & touch controller. More features like quickly turning off the storage devices or gpu also saves power. All of these extend battery life but not the way we want it to achieve.

There is no role of Windows in managing health of the battery. Rather the BMS chip inside of the battery pack does that. After reaching full voltage level the batteries are almost disconnected from the power circuit using Low RDS mosfets. BMS monitor the voltage using only a bridge of resistors. I have checked with the laptop manufacturer it is having a single cell voltage setup of 3.7V Liion battery. May be there are multiple cells, but they are all parallel to each other, so the voltage is 3.7 only. With Full charge the voltage reaches 4.2V & as your PC is always powered through AC the voltage decreases very slowly to 4.1V or hysteresis threshold set by the BMS & resistor bridge. You observed the level reach 100-87 that is seen by the BMS as small change of voltage.

If the PC is run 5 min or more on battery when the battery is at 100 & and may be reaches 95% but the voltage change is beyond the BMS set hysteresis level & it will start charging the battery immediately. You may observe the behavior to check my theory.

There is no such option built in windows that can protect the battery with health charging (60/80% level) facilities.

Hi Tamil, thanks for your reply. But it still doesn't answer the question of how Windows is able to intelligently detect that the charger has been plugged in for a long time, and be able to limit the max charge automatically, without any special app installed on the device. My point is that if it is able to do that automatically, would it be possible for me to set the max charge limit manually; so that even if it gets charged to 100% when the tablet is turned off, when it is switched back on again, and Windows becomes active, it will begin to limit the charge to the value set immediately, instead of waiting for a long time for it to do so automatically—which is how it works at the moment.

Hi CuriosBJ

This is Tamal trying to answer your question.

The battery saving feature you are looking for are generally built in PC BIOS & the battery management system built in with the battery pack. If you let the laptop stay turned off & plugged in then if the BIOS has no such option built in then it will simply charge the battery as its duty to keep the battery charged as there is no communication received from windows power management.

My laptop has the feature to keep battery level at 60/80/100% charge level, but I think your tab does not have such intelligent BMS built in otherwise your Linx PC manufacturer should have bundled a power management app built in where you can tweak the settings.