Laptop batteries won't, of course, give you two days of usage, so it's not necessarily practical to follow that charge-discharge-recharge pattern exactly, but you can get close. Make sure you regularly use your laptop on battery power. Don't work on it with it always plugged into the mains.
Not a well-tended battery
If you do use the mains as your primary power source - as you might well if the notebook's your main machine - at least make sure you use your laptop on battery power a couple of times a week. This is what we didn't do with the netbook. It has stayed attached to its AC adaptor for most of its life, with the battery barely being used.
The connected battery will charge to 100 per cent and then the battery pack's electronics will ensure the cells receive no further charge. At this point, the biggest threat to the battery is heat from the laptop's internals. Make sure your laptop's vents don't become covered. Beyond the heat generated by its operation, a laptop can safely be left connected to the mains.
There's no harm in removing the battery from a laptop that's going to stay connected to the mains for a while. Just make a note of the optimum battery storage conditions - more on this later - and don't inadvertently yank the power cable. With no battery, there's no back-up for your laptop's memory.
Apple machines are an exception, and others may be too: they auto-underclock the processor when the battery's removed, so despite being connected to the mains, they won't run at full strength. We think that's daft, but that's Apple for you.
When you use your laptop on battery power, make sure its charge drops to at least 80 per cent. But don't let it drop to zero. Depending on which operating system you use and how its power settings are configured, you'll get a low-power warning first and, later, your machine will sleep, hibernate or shut down.
At this point, your battery should still be charged to 5-10 per cent of its capacity, and you should now charge it, whether you want to continue working or not. If you're not going to be able to do so for some time, make sure you've saved your work and your laptop's shut down or hibernating rather than sleeping. These two modes turn the laptop off whereas sleeping just keeps it ticking over, but power is still being drained and you run the risk of emptying the battery.
Completely draining the battery is a no-no. Battery manufacturers and laptop makers say that it's a good idea to drain the battery as far as the laptop will allow every so often and to then charge fully in order to synchronise the various capacity monitors within the power pack and the laptop. That ensures that your capacity read-outs are as accurate as they can be.
There seems to be a consensus that daily-use laptops don't really need this, and certainly not on even a monthly basis. Occasional-use laptops, on the other hand, may benefit.
Eking out the charge while your using your computer on battery power is simply a matter of disabling Bluetooth and Wi-Fi if you don't need them, making sure your system spins down the hard drive when it's not required, and - perhaps best of all - dimming the screen's backlight.
How temperature affects a battery's capacity decline
Battery capacity after one year
Source: Battery University
If running to empty or never discharging at all are to be avoided, high temperatures are right out. Batteries' inevitable capacity decline can be slowed by keeping the battery cool.
According to website Battery University, a battery kept full will see its capacity drop by six per cent after a year if it's kept at freezing point. Kept at 60°C, however, the same battery will lose 40 per cent of its capacity to hold charge after just three months.
High heat kills batteries...
...and is a particular problem if you own an Apple laptop which seem to be made for climates with an average temperate of 15C or assume that everyone will be using their laptop in a (cold) airconditioned office.
I live in the sub-tropics and given Apple's unhealthy obsession with 'thin', there is simply no way to keep their batteries cool, even with a cooling pad, a bit cooler yes, but cool, not possible. In the sub-tropics, these batteries get super-hot.
My oldish 17" Powerbook (1.33GHz G4) will quickly build up so much heat it will freeze or shut down entirely if I don't have it sitting on a cooling pad. Even with the cooling pad it killed a new battery within 6 months.
Just out of curiosity, has anyone else had this problem with this laptop model?
Apple: Time to seek treatment for anorexia nervosa.
23 months old
100% capacity available
I have a 3 and a half year old Compaq R4000 which is a desktop replacement laptop with a full desktop Athlon 4000 cpu in it (no sexy low power mobile CPU here).
It also has the standard 6 cell battery and not the bigger capacity which is available.
I use it on power regularly but I always make sure at least once a week I use it on battery till it hits around 15-17% battery left and then charge it up the next time.
After all this time I still get around an hour battery life. Not bad for its age and power usage.
I will get a new battery some time in the future.
Since when did rapid warming cause condensation?
>Rapid warming could cause condensation, and you don't want moisture forming inside your battery pack or laptop
Since when did rapid warming cause condensation?
You're taking a cold battery from a fridge into a warm and possible humid room.
The moisture in the air will condense on the cold battery. Warming it rapidly will actually reduce the amount of condensation present as the evaporation due to heat will start sooner.
However there is no way of telling how much condensation has formed inside the battery, rapid warming or not. Leaving the battery for a few hours first gives it time to warm up to room temperature and also for the condensation to evaporate.
Now all that's needed is putting it into practice
Fascinating. My first laptop was invariably kept with the battery left in and the notebook used on mains charge. Then I took it away and tried to use it on the battery - it lasted about 5 minutes. And THEN I discovered how much Sony charged for replacement batteries.
Since then I have (i) avoided Sony notebooks (and after other experiences, nearly all Sony products) and (ii) tried to preserve the life of the battery by leaving it out of the laptop except for the occasional need to take it off the mains.
Sounds like that's as bad as leaving it in all the time :(
However, I can't help wondering whether the procedures described in the article don't come under the heading of "more trouble than they're worth." Though, I suppose we should all be doing everything we can to maximise resources, and I do hate the thought of shelling out for a new battery to keep an old laptop running.
There's also the question of how welcome a spare battery would be in the fridge ...