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davidfor · 02-24-2013, 07:54 PM

While that video is not exactly wrong, I can't say I like it as advice.

The simplest reason is that there is no reason to leave the laptop off while running the charge part of the calibration. The calibration is simply two or three complete discharge and recharge cycles. It doesn't matter what else happens at that time.

The other problem is the advice to leave the charger on some extra time after the battery reads full. This is useless. When the charger determines a Li-Ion battery is full, it turns off. They cannot be trickle charged. And if someone tries to, it is bad. "Bad" as in damages the cells and could lead to an explosion. For the tiny cell in an ereader, this probably won't be that bad, but for the multiple cell laptop battery, it can be spectacular.

The complete discharge end is also a problem. The suggestion to leave the laptop in sleep for a while is a good idea. For some, a good way to do this is to start the laptop and go into the BIOS and wait for it to run out of power. But, while you are there look and see if the BIOS has a battery calibration function. A lot of laptops do.

For an ereader, it is a bit a harder. Running the battery down takes time. You can't just load a video and leave it running. You need to sit there tapping the screen to use power. Continuously running WiFi syncs would also do it. But using the browser might be the quickest way. That will run the WiFi and will use a lot of CPU downloading and drawing the screen. And if the pages are long and need a lot of scrolling, that should use a lot of power as well.

I'm not sure if calibrating the battery will do anything. I expect the battery level to be simplistic rather than the fuel gauge in a laptop battery. If it is simplistic, it will have a voltages set for the maximum and minimum charge levels and current level will just be the difference expressed as a percentage.

02-24-2013, 07:54 PM	#2
davidfor Grand Sorcerer Posts: 24,905 Karma: 47303824 Join Date: Jul 2011 Location: Sydney, Australia Device: Kobo:Touch,Glo, AuraH2O, GloHD,AuraONE, ClaraHD, Libra H2O; tolinoepos	While that video is not exactly wrong, I can't say I like it as advice. The simplest reason is that there is no reason to leave the laptop off while running the charge part of the calibration. The calibration is simply two or three complete discharge and recharge cycles. It doesn't matter what else happens at that time. The other problem is the advice to leave the charger on some extra time after the battery reads full. This is useless. When the charger determines a Li-Ion battery is full, it turns off. They cannot be trickle charged. And if someone tries to, it is bad. "Bad" as in damages the cells and could lead to an explosion. For the tiny cell in an ereader, this probably won't be that bad, but for the multiple cell laptop battery, it can be spectacular. The complete discharge end is also a problem. The suggestion to leave the laptop in sleep for a while is a good idea. For some, a good way to do this is to start the laptop and go into the BIOS and wait for it to run out of power. But, while you are there look and see if the BIOS has a battery calibration function. A lot of laptops do. For an ereader, it is a bit a harder. Running the battery down takes time. You can't just load a video and leave it running. You need to sit there tapping the screen to use power. Continuously running WiFi syncs would also do it. But using the browser might be the quickest way. That will run the WiFi and will use a lot of CPU downloading and drawing the screen. And if the pages are long and need a lot of scrolling, that should use a lot of power as well. I'm not sure if calibrating the battery will do anything. I expect the battery level to be simplistic rather than the fuel gauge in a laptop battery. If it is simplistic, it will have a voltages set for the maximum and minimum charge levels and current level will just be the difference expressed as a percentage.