Yes, it is true the charging circuit shuts off so the cells cannot be overcharged. It's also true that second to deep discharging, heat is the fastest way to destroy a lithium ion battery - and the heat generated by the system WILL cause it to age faster than it will if it's not subject to that intense heat.
It's true. If you never use the battery power and leave it plugged in all the time, the battery will wear out faster. Good battery practice is to use battery power and recharge regularly. If you are using your laptop as a desktop replacement you can run the battery down to about 60%, remove and store it safely. But it's better to use the battery. Always unplug the adapter from the wall and the computer when you are not using the fully charged laptop.This saves electricity and wear and tear on the battery.
I have a XPS M2010. My manual says:
When the computer is turned off, the AC adapter charges a completely discharged battery to 80 percent in about 90 minutes. Full battery charge time will be longer. Charge time is longer with the computer turned on. You can leave the battery in the computer for as long as you like. The batteries internal circuitry prevents the battery from overcharging.
Nowhere does it say Dell suggests that the laptop not be continually connected to AC.
It does say the main battery should be in the computer at all times for optimal performance and to help preserve BIOS settings.
XPS8300, i7-2600, 12GB DDR3 Ram, AMD HD 6770 Video, ST2420L Monitor, WIN 7 64bit Home Premium
I mean no disrespect by this, so I apologize if this doesn't come out like I intend... but does Dell actually recommend it? I mean, I'm sure it's true because Yahoo has sources and "journalistic requirements" to report accurately, but is there anywhere that Dell actually says to not leave a laptop plugged in while you're using it if it's fully charged?
The warranty on a battery is 12 months (even for Apple's new, vaunted, "5-year" batteries that are not user-replaceable) -- so, no manufacturer is going to care much whether you leave the battery in the system all the time or not. At least when you can (of course Dell now has Apple-style systems with non-removeable batteries like the Vostro 13), you SHOULD remove the battery if the system is run on AC power most or all of the time - while Dell won't care if your battery dies at 15-18 months old, you probably do - and leaving the battery out will prolong its life.
Since this was in The New York Times, I really believe it!!!! This statement makes no sense.
Since the battery circuit shuts charging off (also controls the charging amperage to charge correctly), you do not need to disconnect after a full charge. You will degrade the battery by recharging every several hours. Even if you rarely use the battery, it will probably last longer if left in and plugged in. If you never use the battery, why have a laptop?
My wife's E1705 lasted almost 3 years left in; my M1530 is two years and going strong.
I don't know where the "take the battery out at 80% charge and store it" comes from, but you see it everywhere. I have not seen a single actual study that supports this or any other Li ion battery handling recommendation.
XPS M1530, Windows 8.1 Pro 32-bitInspiron E1705, Windows 8.1 Pro 32-bitDimension 9100, Windows 8.1 Pro 32 bitInspiron 660, Windows 8.1 Home - 64 bitCompaq DX 4370G, Windows 8.1 Home - 64 bitAsus T100 Tablet, Windows 8.1 Home - 32 bit