AC usage when battery is at 100% ? (S7-391)

rAfitiiixxx

Hi everyone!

I've been experiencing the worse tech-support from Acer, i don't have any problems with the ultrabook itself (Acer Aspire S7-391) but i've some doubts about drivers and stuff, that they avoided to respond in many ways. So here is the thing:

Does this ultrabook has any drivers that could make use of the AC power when battery load reaches 100% to avoid battery weathering?

 

The thing is that while i've 100% of the battery and the ultrabook is plugged in to the AC power adaptor it still seems to be draining battery power and re-charging it back to be at 100% all the time.

 

When i ask about drivers, those could or could not be installed, i just need to find out a way to have this feature if possible, and if i can't, i need to know ASAP so i can start unplugging the notebook right after the battery reaches 100%.

 

Thanks in advance.

suniljp

As you mentioned with 2 pin power connector can also disconnect the battery from getting charged. It can disconnect the power source from the battery charging circuit when the battery reaches a particular % charge with the laptop running in AC power source. I do not think your laptop support adjusting the battery charging level to a customised %. Your laptop should have a particular hardware and the BIOS should support that. In some laptops the BIOS has the option to set battery charging level to a particular %. I have read somewhere that windows 8 do not support that feature, older version of windows (Vista) support that feature.

Some write up I found online might help you.

 

Memory Effect

First of all it's necessary to unfold a myth that persists in many peoples head.

The battery memory effect.

In lithium-based batteries this is in fact a myth, it only applies to older Nickle-based batteries. So fully discharging and charging the battery is completely useless and even harmful as we will see below.          

 

The modern lithium battery can be charged regardless of its current percentage, given that it has absolutely no negative effect in its performance.

Should I remove the battery when A/C is plugged in?

Many laptop users have this question and we will answer it right now:

The answer is: YES and NO, it depends on the situation.

Having a battery fully charged and the laptop plugged in is not harmful, because as soon as the charge level reaches 100% the battery stops receiving charging energy and this energy is bypassed directly to the power supply system of the laptop.

However there's a disadvantage in keeping the battery in its socket when the laptop is plugged in, but only if it's currently suffering from excessive heating caused by the laptop hardware.

So:

- In a normal usage, if the laptop doesn't get too hot (CPU and Hard Disk around 40ºC to 50ºC) the battery should remain in the laptop socket;

- In an intensive usage which leads to a large amount of heat produced (i.e. Games, temperatures above 60ºC) the battery should be removed from the socket in order to prevent unwanted heating.

The heat, among the fact that it has 100% of charge, is the great enemy of the lithium battery and not the plug, as many might think so.

Battery discharges

Full battery discharges (until laptop power shutdown, 0%) should be avoided, because this stresses the battery a lot and can even damage it. It's recommended to perform partial discharges to capacity levels of 20~30% and frequent charges, instead of performing a full discharging followed by a full charging.

Laptop batteries contain a capacity gauge that allows us to know the exact amount of energy stored. However, due to the charging/discharging cycles, this sensor tends to be inaccurate overtime.

Some laptops include in their BIOS, tools to recalibrate this battery gauge, which is nothing more than a full discharge followed by a full charge.

So to calibrate the gauge, it should be performed, in every 30 discharge cycles, a full discharge non-stop , followed by a also, non-stop, full charge.

An inaccurate gauge can lead to the fact that the the battery capacity values are are wrong. The battery may report that it still has 10% of capacity when in fact it has a much lower value, and this causes the computer to shutdown unexpectedly.

Discharge (or charge) cycles consist of using all that battery charge (100%) but not necessarily all at once.

For example, you can use the laptop for some minutes in a day, using half its capacity e then fully charge it. If you did the same thing in the next day, it would be counted a discharge cycle and not two, so it may take several days until a full discharge cycle is completed.