Forma Just rebooted on its own ?? without touching it for a day

[davidfor]

Originally Posted by jgbout

Seems to go in and out of sleep properly when you do it.

Here's what happened:

Got it home.
Tried it. Put to sleep.
Plugged in. Charging. Stayed sleep.
Took it later in the night to show family.
Put to sleep and plugged back in. Stayed in sleep.
It stayed on the shelf like that all night and next day no problem.
Later the following night I'm watching TV and notice a flashing on the shelf, about 3 times.
I looked and the reader screen was black (no book cover in sleep).
I picked it up while still plugged in.
3 loading dots appeared on the screen for a few seconds.
Then went right back to last book cover in sleep mode.
Left it rest of night and morning.
Just checked and it comes out and goes in sleep mode fine.

That description sounds like a firmware update. There is an daily sync that happens and if there is new firmware available, it will be synced at that time. There is an option that the device should be setting so that it immediately goes to sleep after install and reboot is finished.

The only reason I question that is that the update should have happened when you did the setup. It can get skipped, but, that would have meant the device had the factory firmware on it. And the home screen should have changed at this point.

Alternatively, something else triggered a reboot. Maybe nickel hung while it was doing a sync or something. It is unlikely to be a faulty device.

[NiMa]

Originally Posted by Uncle Robin

I almost never charge my reader by plugging it into the wall. I connect it to Calibre via my PC so often that its charge stays at a level that works for me. What this does to its battery life, I'm not sure

The best spot to charge it is between 40-80% of its capacity. Lithium doesn't like to be at 0% (actually it can do that a fairly limited number of times), neither always at 100%, so charging it when it's around 35 or 40%, then unplugging it as soon as it reaches 100% should work well.

For InkBox development, I ended up just disconnecting the battery cable on the Kobo Mini so I didn't have to worry about wearing the cells, just leaving it plugged in works (although it might not for newer models).

[davidfor]

Originally Posted by NiMa

Of course. Lithium batteries, when they go near 100% charge, are charged by trickle charging; only small bits of energy are given to the battery sporadically: to keep it near 100% but to also prevent it from burning.
Trickle charging is a great thing in life; but when you use it too much, it can damage the lithium cells and thus shorten the life of the battery.

This is a good read about that.

You might want to check your definition of "trickle charging". Trickle charging is exactly what the words imply. A trickle of electricity is sent constantly. It doesn't turn off, it is applied all the time. For some battery chemistries this is good. For Li-Ion it is a very bad idea.

Li-Ion is charged to a point and the charger turned off. When the voltage drops to a certain point, either by use or self-discharge, the charging turns on again to top up the charge level. In the past, my laptops would drop to a 95% charge before recharging. Current laptops seem to stick closer to 100%. Or maybe the self-discharge is so low I never notice it between times I use the laptop on battery.

But, overall, there should be no issues with leaving any device with a Li-Ion battery in it on charge. Assuming the charging and protection circuits are properly designed. Keeping the battery full isn't the best, but, it is a tradeoff between runtime and overall life. An issue could be temperature. It is likely that a plugged in device is running hotter than the same device on battery (less likely to go to sleep or use any power saving modes). Li-Ion batteries age faster with higher temperatures. But, I would not really expect this to be an issue for ereader.

[jgbout]

I leave my chromebooks plugged in and my older e-reader, never an issue. Neither ever did black screen then just come back on to the sleep page.

[Uncle Robin]

Originally Posted by jgbout

I leave my chromebooks plugged in and my older e-reader, never an issue. Neither ever did black screen then just come back on to the sleep page.

"Why?" remains the question, especially with ereaders. There really is no possibility of gain by doing so, while there is the possibility of loss

[jgbout]

Was just convenient. Never head of not keeping modern devices plugged in. Still didn't hear any connection between that at my device behaviour

I'm just trying to find out what that activity was regardless.

[davidfor]

Originally Posted by jgbout

Was just convenient. Never head of not keeping modern devices plugged in. Still didn't hear any connection between that at my device behaviour

All of these devices should be designed for there to be no problem if they are left plugged in. I don't normally, but, more because I am either using my ereader where it would be inconvenient, or I am swapping them around to do something. But, for my older ereaders, they can stay on power for a while.

I'm just trying to find out what that activity was regardless.

Unless you catch it doing the same thing again, I doubt you will know what happened. These devices can be active when you are not directly using them. Some of that can be turned off, some can't.

[NiMa]

Originally Posted by davidfor

You might want to check your definition of "trickle charging". Trickle charging is exactly what the words imply. A trickle of electricity is sent constantly. It doesn't turn off, it is applied all the time. For some battery chemistries this is good. For Li-Ion it is a very bad idea.

Li-Ion is charged to a point and the charger turned off. When the voltage drops to a certain point, either by use or self-discharge, the charging turns on again to top up the charge level. In the past, my laptops would drop to a 95% charge before recharging. Current laptops seem to stick closer to 100%. Or maybe the self-discharge is so low I never notice it between times I use the laptop on battery.

But, overall, there should be no issues with leaving any device with a Li-Ion battery in it on charge. Assuming the charging and protection circuits are properly designed. Keeping the battery full isn't the best, but, it is a tradeoff between runtime and overall life. An issue could be temperature. It is likely that a plugged in device is running hotter than the same device on battery (less likely to go to sleep or use any power saving modes). Li-Ion batteries age faster with higher temperatures. But, I would not really expect this to be an issue for ereader.

Yeah, that's roughly what I wanted to say. Maybe I didn't explain it too well. Yours is better!
And I agree, for an eReader it shouldn't be too much of an issue, but I can tell from personal experience, after using my Glo HD for about 4 years, putting it in charge normally, and then unplugging it, the battery stayed at a fine level. When I got my Libra, I started to use the Glo HD for more of a development platform, leaving it plugged in pretty much all the time, and now battery life is like 1h30. I couldn't unplug the battery because it would cause the screen not to display anything (I don't know why, maybe the power provided by USB was not enough).

[Pajamaman]

Turn the wifi off. It might have been doing an update. You don't need wifi on all the time, and it uses battery.