sleep or power off: which is more battery friendly?

[Anjohl]

I can't imagine sleep mode being better, as I get TERRIBLE battery life in sleep, which is odd, since I remember reading that eink screens don't consume much if any battery life once a page is displayed. My Kobo touch gets at most 3 weeks in sleep mode.

[jlg432]

I am retired and access my Kobo Glo many times throughout the day. I would assume that powering up 8+ times would be more of a drain than coming out of sleep on a daily basis. I power off at the end of my day and then power up once the next day on first access. In my opinion I don't consider getting 3 weeks out of one charge "very poor" if you read more than 30 mins a day or do frequent power off/on's.

I believe that most of the manufacture claims of duration between battery charges have a daily reading time cap or so many page turns per charge and that this will decrease as the battery wears down.

[moffattm]

Originally Posted by jlg432

I believe that most of the manufacture claims of duration between battery charges have a daily reading time cap or so many page turns per charge and that this will decrease as the battery wears down.

I agree. Manufacturer battery claims are under ideal situations and for very specific parameters (i.e. x number of page turns, x number of start-ups and shut-downs, etc). They should be considered as the very best you can get out of a battery. So many things can affect battery life, such as room temperature, that it's very difficult to compare batteries.

Also the battery meter is really the device guessing the upper and lower limit of the battery. The battery doesn't tell the device that it's at 90%, the device learns over time what the upper and lower limit of the specific battery is, and from that calculates percentage remaining figures. This is why battery calibration is necessary for most modern devices (mobile phones, laptops, tablets, etc).