Kobo Glo HD

[DNSB]

Originally Posted by hooplehead

Some suggestions that could be provided with future firmware updates:
[LIST]
[*]Tapping the "more/less brightness icons" to the left/rigt of the slider should increase in smaller steps, maybe 2%. 5%-steps are too crude. (I'm not even sure why the backlighting can be so bright. Anything above 10% is too bright in a dark room. Maybe I just didn't happen on a use case for it myself yet...)

Not sure if you have run into this yet but one of Metazoa's patches was setting the step size for the backlight. I'm currently using 1%. See the
Instructions for patching firmware 3.16.0 thread for more information.

The patches were originally done by Metazoa. GeoffR is now maintaining the changes needed for each new version of Kobo's firmware along with a multi-platform version of the patch generator.

[murg]

Originally Posted by davidfor

Originals or new?

You mean old or not quite as old?

[TimmyTurnUp]

Originally Posted by MGlitch

You can also disable the header/footer in kepubs so you actually get the full screen. There are a few patches you'd want to enable to prevent glitches but I find it well worth it on my H2O since a primary draw for me was the screen size.

Hi can you please teach me how to do so? I'm not good with customizing things so simple steps would be much appreciated!

[Fbone]

I'm a little disappointed in the battery life of my Glo HD. It seems I need to charge it rather frequently. Since the WIFI is always off, the LEDs must also consume a tremendous amount of power at the brightness I prefer.

[davidfor]

Originally Posted by Fbone

I'm a little disappointed in the battery life of my Glo HD. It seems I need to charge it rather frequently. Since the WIFI is always off, the LEDs must also consume a tremendous amount of power at the brightness I prefer.

How often are you charging? And how much reading time in between charges?

[Fbone]

Originally Posted by davidfor

How often are you charging? And how much reading time in between charges?

Every 5 or 6 days. Maybe 15 hours.

[davidfor]

Originally Posted by Fbone

Every 5 or 6 days. Maybe 15 hours.

Kobo claims "up to 2 months of battery life". I can't see a qualifier for that, but for the H2O it is "Based on 30 minutes of reading a day with ComfortLight turned on or off, and Wi Fi turned off." So, that's about 30 hours. 15 hours seems a bit short unless you are a fast reader (page turns use power, the more page turns, the more power). Or something is blocking the sleep when you are away from it.

I should have asked at what point you are recharging. If you are recharging at 30%, then you are reasonably close to the spec. But, if you are recharging when it runs out, then your not as close.

It is a bit hard for me to comment on the battery usage. It is an unusual day if I don't plug the device in for a bit, plus I have WiFi on all the time. But, I do think that Kobo's estimate is on the high side.

[Fbone]

Thanks for your comments. If Kobo advertises 30 hours, then I am probably meeting their expectations especially with brightness at 100% day and 70% evening. I recharge when the battery indicator falls below 20% so I am not caught out while reading in bed.

In my case the device wouldn't last a week vacation without a recharge.

[Nick_1964]

I read about 2 hours a day but it takes 3 weeks before it went off, you can read hours after the low battery warning.. I have a portable battery that reloads my phone if needed, and use that for my kobo too when I am in bed and place that on my pillow so that when I turn around I don't pull out the cable from a conventional charger, ideal!

[frostschutz]

Originally Posted by Nick_1964

you can read hours after the low battery warning

That's probably not good for the battery though. They like to be charged early. I charge mine when it's below 80%.

[Nick_1964]

Originally Posted by frostschutz

That's probably not good for the battery though. They like to be charged early. I charge mine when it's below 80%.

Nope.. thats not quite right, a battery warning and shut off is always within the safety margins of the battery.
The reader itself is calibrated for the battery usage, so when it is shut off,there is always enough power in the battery to do this safe.
So actually,when the device shut off,the battery isn't totally empty.
A Lithium Ion battery can be damaged when really totally empty,but the cirquit prevents this and you will normally never reach this point.
It is totally safe to read until the device shut off, the warning is there only to tell you that if you don't charge you can't read anymore, it isn't telling you that it is dangerous to read any longer or the battery get's damaged.

In android devices, the battery stats file tells your reader when to start or stop,it is build by the battery cirquit itself, if you delete it (dangerous) there is most of the time 10% extra in the battery itself.
In a lot of cases,when a device is working shorter and shorter,it is only the file that is corrupt and not the battery itself,there are tools to re calibrate it (only by rooted devices and only by a professional person,it must be done by following a certain routine..)

[frostschutz]

Originally Posted by Nick_1964

It is totally safe to read until the device shut off, the warning is there only to tell you that if you don't charge you can't read anymore, it isn't telling you that it is dangerous to read any longer or the battery get's damaged.

It's telling you to charge. But it's a religion, I guess. You can find sources for either belief in the world wide web, here's mine:

Originally Posted by https://en.wikibooks.org/wiki/Battery_Power/Lithium_Ion_Batteries#Guidelines_for_prolonging_Li-ion_battery_life

・Lithium-ion batteries should be charged early and often.
・Lithium-ion batteries should never be depleted to empty.

[Nick_1964]

Originally Posted by frostschutz

It's telling you to charge. But it's a religion, I guess. You can find sources for either belief in the world wide web, here's mine:

"・Lithium-ion batteries should be charged early and often.
・Lithium-ion batteries should never be depleted to empty."

When you read what I told, you see that i tell you exactly the same.
You can damage a Lithium-ion battery if you use it completely to empty but the cirquit in the reader prevents you to do that.
So again,when the device shut off, there is at least 10% reserve in the battery, hence: it is not empty and therefore will not be damaged.
Your quotes are guidelines for just plain battery's without any device and without any cirquit.
So if you would take the battery out of the device and you put a lamp or something on it and completely empty it,that could be ruin the battery.
Inside the device it never happens,the cirquit prevents it.
So you can safely read until it stops.
When you plug it in after that to an external device like a computer you will see that it comes directly to life with full light, why ?
1.because you plug it in to a device that powers it, but 2.:because there is enough power left in the battery.

From Kobo itself:
"If and when the battery will die while reading, the screen will remain on that page. It will appear that the eReader is frozen but it simply needs to be recharged."

[frostschutz]

Originally Posted by Nick_1964

when the device shut off, there is at least 10% reserve in the battery

So ... where is that mysterious 10% reserve coming from? Is the battery lying about its own charge level? Is it in the Linux kernel? Is it the Kobo software that reports it differently?

I can tell you that Kobo software reports exactly what the kernel driver reports and in the kernel driver I don't see any shenanigans (but then I'm not a kernel developer).

The Kobo software displays a big ass warning in a popup window as soon as the battery reaches 10%. If it was not critical I think they'd have gone for something less obstrusive like a battery icon in a screen corner or something.

If you see that warning you should charge pronto. In the future you should charge sooner so the warning never comes up. At least that is what I would recommend for the Kobo and any other device really… if you know better, it's up to you.

Originally Posted by Nick_1964

When you plug it in after that to an external device like a computer you will see that it comes directly to life with full light, why?

The USB cable provides enough power for the device to run and then some. There has to be surplus otherwise you could not charge at all and particularly not make a difference within a short time frame. The status of the battery should not matter while a cable is connected, in fact unless some circuitry prevents it you should be able to use it with the battery removed entirely.

Originally Posted by Nick_1964

From Kobo itself:
"If and when the battery will die while reading, the screen will remain on that page. It will appear that the eReader is frozen but it simply needs to be recharged."

Maybe that was the case with old Kobo readers. When reaching 1% capacity the H2O displays a black screen that says you have to charge the device. If it freezes on a text page it probably means the battery went flat unexpectedly.

Of course, I haven't actually tried it with actually discharging the battery. I just fiddled with the values reported by the kernel driver and the black screen is how the Kobo software reacts to a fake 1% charge. I don't know if it manages to do that if the battery actually discharges naturally, because I don't let it do that. I'd rather not have to replace my battery sooner than necessary

[Nick_1964]

Originally Posted by frostschutz

So ... where is that mysterious 10% reserve coming from? Is the battery lying about its own charge level? Is it in the Linux kernel? Is it the Kobo software that reports it differently?

Again READ !!
It is coming from the hardware build in cirquit. (I don't know if it is exactly 10%,just called this percentage as a example)
THAT system is telling the battery is low power or lost and have a safety margin to prevent the battery from being killed. Where or how that is hidden or implemented is not important.
Then it just stops responding.
It is the same system that the other way around prevents you from overcharging.
If it is not in the firmware of kobo, it is in the device itself.
There is more running on the device than only the kobo firmware.
Try not to trap me, the most important is:
The low battery warning is only telling you that the device will stop running soon, it is not a "danger now you will kill your battery if you don't stop" warning.

Just enter : li-ion discharge protection circuit into Google.


It is the same as using a Litium-Ion battery in your laptop, yes for sure it is better to charge when the system warns you to do so because you don't want to loose your data that isn't saved.. if you continue working,the laptop will stop and the last data isn't saved.
But it doesn't damage the battery.
It can when you store it at that level and wait a couple of months,then eventually other things drained the battery, and then it can be empty or damaged.
But even my flashlight litium ion battery has a chip at the bottom preventing this from happening.
The factory of the battery always charge it and the chip in it prevents it from working when it dropped under a level of mah and even then it guarantees that it need 10 years from the point that it stops until total destruction. ("rechargable battery with re/discharging protection cirquit" is even printed on it)
In android devices,as I told,the battery stat system controls a part of it. (don't know if the kobo is android based but that is not important as all modern li-ion battery's have the cirquit.)

I end the discussion here,I don't want to bother people or scare them,if wanted you can go further with the discussion by private messages.