Glo Bad battery?

[Mrs_Often]

Originally Posted by VelvetElvis

Finished charging this replacement Glo last night at 6:00 PM and immediately put it to sleep, with WiFi off. This morning at 9:00 AM, it's at 72%

I put only 2 books on it when I received it (after updated the firmware.) Opened the active one, scrolled past the credits and TOC to the first page of chapter one, then put it to sleep. I might add that I read this same book on my Sony, and it caused no problems at all.

Very disconcerting, but I'm going to wait a few more days before contacting Kobo again.

Sad faced smiley indeed! So the book is "open" while the Glo slept for the night. Have you looked at the chapter structure of the book? Despite jusmee's insights I still believe the book can influence battery drainage. Larger books also cause the battery to drain faster than smaller books.

Still, 28% drop is ridiculous How many cycles has the battery had now? Perhaps the drop will get slower now that it's lower, coinciding with the non-linear gauge theory.

On another note: haven't heard back from Kobo yet! I contacted them twice last week about bad books and got responses with a day... it's been 2.5 days now. I'm still patient though.

[samhy]

Originally Posted by Mrs_Often

Still, 28% drop is ridiculous How many cycles has the battery had now? Perhaps the drop will get slower now that it's lower, coinciding with the non-linear gauge theory.

Ridiculous, indeed.
In my experience, not only with reading devices, the higher the battery, the slower the drop and vice-versa. I really hope I am wrong, tnough

[moffattm]

Originally Posted by jusmee

Really, these devices use memory chips to store the data in cache, and I am sure you can't power up half a memory chip. Sleep mode has to maintain the same amount of memory no matter what.

That is exactly what I thought too when the idea of the size of the book's cache affecting battery life came up. Surely the whole memory is being kept alive by the battery when the device is in sleep mode, not just the portion of memory being used. It would be way too hard to figure out which parts of the memory are being used and to power just those parts (even if it was possible to power individual memory chips, and is there even more than one memory chip in the Kobo's?) Also, stuff normally isn't necessarily stored in a contiguous chunk of memory, it's common to have stuff all over the place as chunks of memory are allocated and freed by the OS.

Note I'm looking at this from a programmers perspective, I don't know all that much about the actual Kobo hardware.

[VelvetElvis]

Originally Posted by Mrs_Often

Sad faced smiley indeed! So the book is "open" while the Glo slept for the night. Have you looked at the chapter structure of the book? Despite jusmee's insights I still believe the book can influence battery drainage. Larger books also cause the battery to drain faster than smaller books.

Still, 28% drop is ridiculous How many cycles has the battery had now? Perhaps the drop will get slower now that it's lower, coinciding with the non-linear gauge theory.

On another note: haven't heard back from Kobo yet! I contacted them twice last week about bad books and got responses with a day... it's been 2.5 days now. I'm still patient though.

The chapters appear fine to me. I'm not an expert, but the few chapter links I tried were fine. I should reiterate that the book (Inside Scientology) worked just fine on my Sony. In fact, the only issues I've had on either of my Sonys were the very odd wonky epub that would hang the reader. Tweaking them through Calibre generally fixed them.

The battery has dropped from 72% to 46% in 24 hours. It's only had 2 depletions/charges since being received, but I doubt this is a calibration issue.

Not sure why I'd have 2 bum Glo's in a row. Out of 2 Sonys and 3 Kobo models, this is the only one that's given us trouble. If it's an issue of not being able to deal with side-loaded epubs, then it's absolutely useless to me. I can't see that being the case though.

It's unfortunate Kobo hasn't gotten back to you yet on your problem. What I do in customer service cases like these, is keep a complete log of all events, contact attempts, etc.

[Mrs_Often]

Originally Posted by VelvetElvis

The chapters appear fine to me. I'm not an expert, but the few chapter links I tried were fine. I should reiterate that the book (Inside Scientology) worked just fine on my Sony. In fact, the only issues I've had on either of my Sonys were the very odd wonky epub that would hang the reader. Tweaking them through Calibre generally fixed them.

The battery has dropped from 72% to 46% in 24 hours. It's only had 2 depletions/charges since being received, but I doubt this is a calibration issue.

Not sure why I'd have 2 bum Glo's in a row. Out of 2 Sonys and 3 Kobo models, this is the only one that's given us trouble. If it's an issue of not being able to deal with side-loaded epubs, then it's absolutely useless to me. I can't see that being the case though.

It's unfortunate Kobo hasn't gotten back to you yet on your problem. What I do in customer service cases like these, is keep a complete log of all events, contact attempts, etc.

Man that sounds very un-fun. I can't imagine that being a calibration issue either, and it indeed doesn't sound like it's a wrongly formatted epub. I strongly doubt it's a sideloading issue as well as the same firmware on the Touch has no issues. Kobo got back to me today with not very helpful comments for me, but maybe they'll be useful for you so I posted them in the spoiler. They basically state that the light will use lots of battery so if I constantly use that, that could be my problem. But come on... 5 days? Nonsense. Especially not as it's in sleep mode most of the time and I hardly read on the Glo whilst testing so not much light was used at all.

Spoiler:

Hi "Mrs_Often",

Thank you for contacting Kobo Customer Care. We apologize for any inconvenience, please follow the next steps to help rectify the issue and get back to us if the battery still only last for half of what is suggested. Also keep in mind that using the light will deplete the battery faster than normally, so even a replacement could be the same so if you use this feature constantly keep in mind battery will last less longer.

If your eReader appears to be frozen on one page, or will not turn on, try these steps to resolve the issue:

Ensure that you have charged your eReader for three hours using the micro USB cable that came with it
Try charging with a different USB cable
Try charging using a different USB port
Try charging using a different computer

Complete a basic reset

A. Straighten a paper clip
B. Find the hole to the left of the USB connector
C. Poke the paper clip into the hole until it clicks
D. Remove the paper clip

If issue persists continue below

Power the device off and then on again

A. Slide the power button to the right for 5 to 6 seconds to turn it off
B. Wait 15 seconds
C. Slide the button to the right again to turn it on

If issue persists continue below

Completing a Factory Reset

Warning: a factory reset on a Kobo Glo returns the device to its 'out-of-the-box' condition - all updates, documents, and books will be deleted - however, a sync will restore the Kobo Library

INTERNAL:
A. Press the Home icon
B. Tap the Settings icon (three lines, upper right)
C. Tap Settings
D. Tap Device Information
E. Tap FACTORY RESET
F. Tap RESET NOW
G. Re-Setup your Device with the Kobo Desktop when you see the eReader & Cable picture on the Screen

EXTERNAL:
A. With the Device Turned On
B. Press and Hold the Light Button on Top of the Device
C. Then use a Paperclip in the hole on the Bottom until it clicks
D. The Power Light will blink RED twice
E. When the Light turns GREEN, Let go of the Light Button
F. The Light should start to flicker WHITE, and will continue to flicker while it resets itself
G. Re-Setup your Device with the Kobo Desktop when you see the eReader & Cable picture on the Screen

Please let us know if you have anymore questions and concerns.

Sincerely,

The Kobo Team.

I contacted them again explaining I tried all that prior to contacting them (as I had also already stated in my first e-mail), and gave them more specific details of the length of the battery life for all the cycles I tested. So, I'm now awaiting a follow up reply.


EDIT: I just got that follow up reply. Nice and quick! This time it's simply "my device will have to be replaced/repaired" and please provide your details (that I'd already given, but oh well). So, eagerly waiting to know what the rest of the procedure is going to be!

EDIT 2: Reply 3 tells me I'll get a replacement But I have to send my Glo first and pay for insured postage, luckily within the Netherlands so that's ok.

[murg]

Originally Posted by moffattm

That is exactly what I thought too when the idea of the size of the book's cache affecting battery life came up. Surely the whole memory is being kept alive by the battery when the device is in sleep mode, not just the portion of memory being used. It would be way too hard to figure out which parts of the memory are being used and to power just those parts (even if it was possible to power individual memory chips, and is there even more than one memory chip in the Kobo's?) Also, stuff normally isn't necessarily stored in a contiguous chunk of memory, it's common to have stuff all over the place as chunks of memory are allocated and freed by the OS.

Note I'm looking at this from a programmers perspective, I don't know all that much about the actual Kobo hardware.

From memory:

Kobo uses Freestyle processors in the devices, and these processors are basically system-on-a-chips, which means that the CPU and the memory are on the same chip.

The chip may be smart enough to be able to turn off portions of memory that aren't being used, but there isn't that much memory, and stuff tends to get written to semi-random memory locations, so I'd say that all of memory is either on or off.

During sleep mode, memory will be in a sleep mode, where only enough power to refesh it is consumed. When the appropriate hardware trigger (power button toggle) happens, then the processor and memory are awakened, and the device is back in business.

[murg]

Having recently taken a long aeroplane trip, my Glo stayed on 100% for about 6 hours of lighted reading, and then dropped about 2% for every 2-3 hours after that, with non-reading periods being in sleep mode.

I think that Kobo should load 'average' battery use data at the factory, and then adjust this as necessary. With modern manufactoring processes, a vast majority of the batteries should have similar charge/discharge rates, and loading the 'average' rates initially would mean that the battery usage percentages are more correct, out of the box.

[jusmee]

Originally Posted by murg

From memory:

Pun intended?

Originally Posted by murg

Kobo uses Freestyle processors in the devices, and these processors are basically system-on-a-chips, which means that the CPU and the memory are on the same chip.

The chip may be smart enough to be able to turn off portions of memory that aren't being used, but there isn't that much memory, and stuff tends to get written to semi-random memory locations, so I'd say that all of memory is either on or off.

During sleep mode, memory will be in a sleep mode, where only enough power to refesh it is consumed. When the appropriate hardware trigger (power button toggle) happens, then the processor and memory are awakened, and the device is back in business.

All of which means power usage should not be book or book-size related.

[moffattm]

Originally Posted by murg

From memory:

Kobo uses Freestyle processors in the devices, and these processors are basically system-on-a-chips, which means that the CPU and the memory are on the same chip.

The chip may be smart enough to be able to turn off portions of memory that aren't being used, but there isn't that much memory, and stuff tends to get written to semi-random memory locations, so I'd say that all of memory is either on or off.

During sleep mode, memory will be in a sleep mode, where only enough power to refesh it is consumed. When the appropriate hardware trigger (power button toggle) happens, then the processor and memory are awakened, and the device is back in business.

Thanks for confirming that for me. So the amount of memory that a book uses should have no affect on power usage while the device is asleep.

I can understand poorly formatted ebooks (i.e. books that have all their chapters in one huge file instead of splitting into multiple smaller files) having an affect on the processor (i.e. making the processor work harder by having more data to shunt around), but this should only be while you're opening or reading the book, not while the device is asleep. Do you agree?

[Namekuseijin]

well, well, my 2 cents as a possible buyer for a Glo:

1) I'm lucky I don't travel as much like you guys to distant savage lands and live in a house with electrical system so I can charge it every week or perhaps even daily if it's that bad

2) I'm not amused that a lit screen draws more power than a non-lit one

[Mrs_Often]

Originally Posted by murg

From memory:

Kobo uses Freestyle processors in the devices, and these processors are basically system-on-a-chips, which means that the CPU and the memory are on the same chip.

The chip may be smart enough to be able to turn off portions of memory that aren't being used, but there isn't that much memory, and stuff tends to get written to semi-random memory locations, so I'd say that all of memory is either on or off.

During sleep mode, memory will be in a sleep mode, where only enough power to refesh it is consumed. When the appropriate hardware trigger (power button toggle) happens, then the processor and memory are awakened, and the device is back in business.

Ah good to know.

Originally Posted by murg

Having recently taken a long aeroplane trip, my Glo stayed on 100% for about 6 hours of lighted reading, and then dropped about 2% for every 2-3 hours after that, with non-reading periods being in sleep mode.

I want that!
I know I'm getting a replacement Glo, but looking at VelvetElivs' experience... sounds like there's lots of bad batteried Glo's out there

Originally Posted by jusmee

All of which means power usage should not be book or book-size related.

Yes. And if that's true, I could have known from the beginning my Glo's battery was crap.

Originally Posted by moffattm

I can understand poorly formatted ebooks (i.e. books that have all their chapters in one huge file instead of splitting into multiple smaller files) having an affect on the processor (i.e. making the processor work harder by having more data to shunt around), but this should only be while you're opening or reading the book, not while the device is asleep. Do you agree?

That would seem logical, yes, assuming all the above is indeed correct. Perhaps it only seemed like a larger battery drop in sleep mode because the battery meter caught up with the battery that had actually lost the power during reading?

Originally Posted by Namekuseijin

well, well, my 2 cents as a possible buyer for a Glo:

1) I'm lucky I don't travel as much like you guys to distant savage lands and live in a house with electrical system so I can charge it every week or perhaps even daily if it's that bad

Of course, it's not all that dramatic. But still, if I get a device that wants charging every 5 days while I should at least get 14-30 days out of it, I'm not happy. I don't want to have to worry about making sure it's charged enough. I just want to use it.

Originally Posted by Namekuseijin

2) I'm not amused that a lit screen draws more power than a non-lit one

Not amused? You mean you expect a light source to not use any battery? Of course it uses battery. The question is exactly how much it uses... Kobo warned me after my first mail that light usage might be the culprit, but they were just saying that without looking at my numbers. If you use the light constantly, you should still get more than 5 days' use out of your Glo. Like murg described, he used the light for 6 hours with no battery drop at all... (well, not battery meter change).

[Woodstonian]

Battery life depends on individual usage, so actual results may vary. One month of battery life is based on reading 30 minutes per day, turning 1 page per minute, with ComfortLight turned on OR off

This quote comes from the Kobo Glo site http://www.kobo.com/koboglo

I recall seeing other estimates that supported the position that use of the light had little impact on battery life, but I can't locate them right now.

[murg]

Originally Posted by moffattm

Thanks for confirming that for me. So the amount of memory that a book uses should have no affect on power usage while the device is asleep.

I can understand poorly formatted ebooks (i.e. books that have all their chapters in one huge file instead of splitting into multiple smaller files) having an affect on the processor (i.e. making the processor work harder by having more data to shunt around), but this should only be while you're opening or reading the book, not while the device is asleep. Do you agree?

In general, in sleep mode, the size of the book should not be a factor in battery usage. During sleep mode, the processor should only be refreshing memory, and looking for a hardware interupt, which in this case is the power button being flicked or the usb cable being connected.

It may be possible for the processor to be smart enough to only refresh part of the memory, but then you have to be able to tell the processor which parts of memory are containing valid data. My opinion is that both the Kobo firmware and the processor itself is not up to this task. If they were using an ultra-low power processor, then maybe.

So, during sleep mode, the battery usage should only be dependent on the requirements to keep the memory refreshed and scan for the hardware interrupt (if it has to scan for this), regardless of which book (or any) is currently loaded.

[murg]

Originally Posted by Mrs_Often

I want that!
I know I'm getting a replacement Glo, but looking at VelvetElivs' experience... sounds like there's lots of bad batteried Glo's out there

My battery had not gone through a series of charge/deep discharge cycles, so the calibration may have been off a bit...

[VelvetElvis]

Originally Posted by Mrs_Often

Man that sounds very un-fun. I can't imagine that being a calibration issue either, and it indeed doesn't sound like it's a wrongly formatted epub. I strongly doubt it's a sideloading issue as well as the same firmware on the Touch has no issues. Kobo got back to me today with not very helpful comments for me, but maybe they'll be useful for you so I posted them in the spoiler. They basically state that the light will use lots of battery so if I constantly use that, that could be my problem. But come on... 5 days? Nonsense. Especially not as it's in sleep mode most of the time and I hardly read on the Glo whilst testing so not much light was used at all.

Yet in other posts I read claims that the light uses a negligible amount of battery. Hmm...

EDIT 2: Reply 3 tells me I'll get a replacement But I have to send my Glo first and pay for insured postage, luckily within the Netherlands so that's ok.

Well at least you're getting some action. I hope it doesn't take long to exchange.