Does the battery get used when fully charged ??

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proximiti99

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My Dell used to be on charge almost 90% of the time, and after three odd years the battery power was almost as good as new. Now I leave my HP on at work. I wonder if the battery is active during this period. I mean, one can use the laptop without the battery, while plugged into mains.
Does the battery get used whilst fully charged :rolleyes:
 
Well I just found out that Litium Ion batteries have a lifespan. Irrespective if they get used or not they shall be wacked in x amount of years, mmm. So using the laptop off the mains without the battery is a waste if this is a fact :rolleyes:
 
xeo57 said:
Irrespective if they get used or not they shall be wacked in x amount of years, mmm.
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That does not sound right. The lifespan is what the average user can expect not the time limit till the battery dies like vrot milk.

Afaik its is better to leave it unplugged...but the hassle isn't worth it for many.
 
Well, my source for the above is PC Format current issue. They say that even if you don't use the Li-Ion battery, it shall be wasted when it's time is up ...
 
Do the following with batteries: If you run it off the mains the whole time, discharge the battery to 30% and store it. Otherwise if you occasionally use it, remove it when you run off the mains.
I was told this by the HP guys in the States. My battery was around 14 months old when it suddenly died on me (ie doesn't work anymore). Turned out to be a hardware failure, 2 months out of warranty :(
 
xeo57 said:
Well, my source for the above is PC Format current issue. They say that even if you don't use the Li-Ion battery, it shall be wasted when it's time is up ...
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Still doesn't make sense to me..but I'm using a PC not laptop mostly so it's not an issue for me either way.
 
My thinking on this matter would be that batteries don’t have an indefinite shelf life. That is, if it is made today, after x amount of time it will be useless whether it has been used or not. I would then hazard that the x amount of time must be related to actual battery usage. So if you hardly use it, it should last longer than a battery that is used constantly.

I would also guess that when fully charged and plugged into the laptop that it does get used.

Power ---> Battery ---> Laptop. My guess is that only when there is no battery plugged in do you get Power ---> Laptop. If the power bypassed the battery when it is plugged in, how else would it get charged? I guess those who are electrical types might know of how the circuitry can be designed to bypass the battery when it is full.
 
Li-ion chargers stop charging the battery when detected as full. A Li-ion battery can be dangerous if improperly charged.

All batteries have self-discharge, this is when they are charged up and then left open circuit for a period of time. It varies amongst the different types.
 
milomak said:
My thinking on this matter would be that batteries don’t have an indefinite shelf life. That is, if it is made today, after x amount of time it will be useless whether it has been used or not. I would then hazard that the x amount of time must be related to actual battery usage. So if you hardly use it, it should last longer than a battery that is used constantly.

I would also guess that when fully charged and plugged into the laptop that it does get used.

Power ---> Battery ---> Laptop. My guess is that only when there is no battery plugged in do you get Power ---> Laptop. If the power bypassed the battery when it is plugged in, how else would it get charged? I guess those who are electrical types might know of how the circuitry can be designed to bypass the battery when it is full.
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I hear you, but don't you think that since the laptop can run off the mains directly, the same switchover occurs when the battery is full? I mean, when the battery is fully charged, it shows "On AC Power" instead of "On Charging 75%". Maybe someone here has a definite answer on this?
 
Skeptik said:
During a power cut (we've all been there) does it automatically switch over instantly??
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with the battery plugged in, it would be no different from pulling the mains out yourself? that shouldn't cause the laptop to power down.

so i guess the question is what happens when you pull the battery out while the mains are plugged in?
 
so i guess the question is what happens when you pull the battery out while the mains are plugged in?
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Exactly, I presume the laptop will switch over to mains ? Or not ?
 
took the battery out with mains connected, continued to chug along.
 
From what I understood, Li-Ion lifespans can be prolonged by being stored at around 40% charge at low temperature. But yes, it will decay even if not used at all.

Otherwise it's still a case of the deeper the discharge, the more damage to the structure of the battery. A battery could get 25 20% discharges with that the same damage as 20 40% discharges for instance. A 100% discharge would severely damage the battery, but usually there is circuitry in place to protect against this.
 
what does the above mean? That it is best to remove the battery when it is near empty rather than near full?
 
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