Battery Re-Charging Software Controlled

[lulzfish]

If you leave your laptop on the mains at all times, with the battery in, and at 100% charge, you will end up with a battery that takes no charge after a relatively short time. 100% charge plus the heat inside a laptop (compared to a phone or other handheld) degrades the battery quickly.

Really? My laptop's on all the time, plugged in, with the battery in, and the battery still lasts a couple hours even after regularly using it this way .. basically all year.

I'd also like to remind the people who don't read everything that the Pandora will barely get above room temperature (or skin temperature if it's in your pants), so there's no concern of temperature degrading the battery any faster than normal room temperature would.

 

[hobbyman II]

same as Lulzfish, all my lappys have the Battery pack in all the time, our power is so unreliable out here that you need it as a UPS to prevent losing data when the power drops out (1-4 times a month), that's the reason I switched all my main computers to laptops (apart from my Windows XP based desktop that I use for gaming).

 

[Tor]

If you leave your laptop on the mains at all times, with the battery in, and at 100% charge, you will end up with a battery that takes no charge after a relatively short time. 100% charge plus the heat inside a laptop (compared to a phone or other handheld) degrades the battery quickly.

Really? My laptop's on all the time, plugged in, with the battery in, and the battery still lasts a couple hours even after regularly using it this way .. basically all year.

That will depend on the internal temperature of the laptop, and also on the charging level the laptop uses. Here where I work we have lots of laptops everywhere, sitting in offices and meeting rooms, always on the mains. Every single one of them have useless batteries, at least after a year. But the models we use (Fujitsu Siemens, some HPs) get a bit hot. My own old Compaq was the same, after the previous owner's use. I got a replacement battery, and I actually remove the battery when I'm on the mains, or, if I don't bother with that, I run on battery and charge it later when it's off. The battery must be some five years old now, and I can still do 3.5 hours or more of continuous work (hacking code in emacs).

However, some new laptops now have an option to charge to just 80% or less, and that is presicely because they handle temperature degradation better that way.

I'd also like to remind the people who don't read everything that the Pandora will barely get above room temperature (or skin temperature if it's in your pants), so there's no concern of temperature degrading the battery any faster than normal room temperature would.

Indeed, this temperature issue should not be a problem for our Pandoras. And, unlike a laptop, you can just keep using it on battery for very long periods without worrying about a run-down battery. So the usage pattern is different from a laptop, and there's not any temperature problem, or certainly not to the same extent.

 

[Yoyobuae]

My work laptop is pretty old, not sure how much though. It heats up by some amount (the heat is easily felt on the palm of my hands, not uncomfortably hot though). The battery quits at around 50% charge. Tried doing a full charge/discharge cycle to recalibrate the fuel gauge circuit, but it didn't help.

So I assume the continuous heat crippled this one.

 

[Izomiac]

If a battery is kept charged at 100% capacity, then at room temperature it'll lose about 20% of it's total capacity after a year. However, if kept at 40% capacity only 4% of the total capacity is lost.

I can only surmise that marketing (XX hours of battery life!) and simple programming is the only reason most portable devices charge all the way to 100%. I've got a drawer semi-full of old lithium ion powered devices rendered useless by this practice. IMHO the default should be something like 70% charge and provide an "overcharge" option for anyone who needs longer runtimes and doesn't mind replacing the battery after a year or two (i.e. the point that the total battery capacity would have degraded to less than 70% of the original capacity).