Originally Posted by VelvetElvis
Yes, it's a brand new one. At least, it has all the appearances. New, sealed box, protective screen cover, etc.
However, I'm not liking the initial results. WiFi off, fully charged, it's dead in 4 days. I'm hoping it's a battery calibration thing, but I have my doubts. It currently has the same book on it that I read on my Sony with no issues whatsoever.
What I may resort to doing, is having my GF use her old Kobo WiFi. Then I will put the same book/books on both her Touch and Glo, charge them both, put them to sleep, and monitor the results.
I'm wondering if these battery issues are exclusive to sideloaded epubs?
Yay at getting a new one! But...
Oh my, 4 days!! That is horrible! You won't know until you've had a couple of full battery cycles though but still, doesn't look good
As for sideloaded epubs, see below.
Originally Posted by jusmee
I still don't believe battery issues are caused by a data file. I have read no plausible explanations as to how this is possible.
I also still believe you need to have the device power off, not just sleep, to get the long battery life we expect from an e-ink device.
I'm absolutely positive that battery drain can
be caused by a data file. I tested myself, and I know that kepubs are read by loading a full chapter into cache to accommodate fast page turning. So the longer the chapter, the more has to be stored in cache and the more battery charge is used. I have found two badly formatted kepubs so far that had multiple chapters per chapter (so lots of missing chapter marks), causing a lot faster battery drain than expected, and Kobo acknowledged this and also gave me a refund for both books.
The epub version of the kepub drained the battery a lot less fast, so apparently either the epub reader is more efficient or an entire chapter isn't loaded to cache for epubs; I don't know how it works. So VelvetElvis, no, I don't think it's "just" sideloaded epubs that have these battery issues.
(If you'd like to try it out with kepubs: "Absolute Power" by David Baldacci and "Raven Black" by Ann Cleeves both lack a lot of chapter marks in the kobo store.)
And the sleep/off difference: yes, of course you'll get longer battery life if you power off instead of sleeping. But 4 days of battery life in sleep mode is ridiculous. And, comparing with my Touch: it's been on constant sleep mode now for 9.5 days, with a book loaded, and its battery is at 74%. That gives an estimate of 30 days of life in sleep mode.