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Sony Pledges More Accurate Laptop Battery Figures
Slatterz writes "Ever wondered why you never get the 10 hours of battery life advertised with your new ultraportable? Battery life ratings have been a joke for years, so it's interesting to hear that one big vendor is picking up its game. PC Authority says Sony is abandoning the usual (and wildly misleading) JEITA method for coming up with those 10+ hour battery numbers (they're still using JEITA, but not the usual way). Interestingly, the story has links showing the old and new steps Sony takes to come up with those battery predictions. It's good to see the industry coming clean on this issue."
built in the 1980s.
It runs for approx 2 weeks continuously, on 4 AA rechargables, and I just dump my notes as a .txt file to my desktop.
If people made a more sophisticated version, with network capability and OpenOffice formatting, I'd buy it like a shot. Modern batteries would also run it for months.....
If you're going to be pedantic, get it right. Batteries are measured in amp-hours, and if you want to use watts, it would be "watt-hours at X volts", whatever the voltage is that the battery is supplying.
The Lenovo X61 extended battery has 4400 mAh, or 4.4Ah, so if it lasts eight hours at a draw of 9 watts, then it's drawing about 16 volts.
9 watts at 16 volts is 0.55 amperes. 0.55 amperes for 8 hours is 4.4 amp-hours.
It's more fun not having to think this much on a Monday morning.
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This is close, but not quite accurate. Macs enter sleep mode as any other PC does. However, when they enter sleep, they also begin paging everything out so that they can hibernate if the battery gets too low while still sleeping. You can tell whether or not your mac hibernated easily. If it wakes up instantly on a key press it was sleeping. If it needs the power plugged in, and comes back to a greyscale filtered version of what you were working on and a progress bar, then it was hibernating.