Kobo Battery problem

[porphyry5]

Originally Posted by davidfor

The battery is a single cell. From my experience, the discharge rate of Li-Ion cells is not linear. But, it shouldn't be that bad.

The real question is whether something is happening to use the battery while sleeping. I can state that my Clara HD does not do that. But, I have had some issues with syncing on it recently that have meant the sync runs for a long time and frequently doesn't complete. And that drains the battery. Plus doesn't let it sleep properly. Something like that would explain battery drain like you are reporting.

There have been other issues over the years related to problems with the reading part of the app that can be triggered by problems in some books. In those cases, something is left running when the book is closed and quickly uses a lot of battery. Restarting the device will kill the rogue process and the battery usage returns to normal. If you see this happen after a particular book, we can look at it to work out what is wrong. We may be able to fix the problem in the book and the problem will go away. And you can report the issue to Kobo so they can fix it from their end.

Can't be a Sync problem, I never sync my devices, always keep them in airplane mode unless I specifically need internet access. Actually I did that in self defense when I used to have a kindle, Kobo isn't intrusive, but old habits die hard.

Your second point is a possibility so I'm testing it now by deliberately turning it off each evening instead of just letting it sleep. I'll report back again in a couple of days whether it makes a difference.

[Phil_C]

After the last full charge, the Clara once again acted properly until the battery reached 30%.

Late yesterday, it was at 33%. This afternoon I read for a few minutes and left it at 31%. A couple of hours later, I opened the cover and it was at 30%. I began to read and after the second page turn it was at 18%. I closed and opened the cover and it was at 12%.

I shut it down and restarted. It came up at 10% with a warning. I walked over to my desk to charge it, and it was at 6%.

So it seems I must figure that 30-35% is really about 0% and charge it immediately. I'm getting less than three weeks out of it per charge, half of what it was six months ago. It is only 30 months old. It took previous (Sony) readers 5+ years to get to that point -- and the batteries did not drop off so radically at the end of each usage cycle.

I don't expect any ereader to last forever, and I love my Kobo, but I call this poor performance.

[acprinter]

My Kobo Clara also does well until it hits 50% and then drops to 0% overnite. I am sticking with my Paperwhite, I like it better anyway.

The Clara was a poor investment.

[Fozkas]

That is "normal" on the kobos. At least in all that gone through my hands.

Battery is prety good until about 50-40, from there is quite quick to 0

[RodRiquez]

My Clara HD started doing this (get to <50%, then rapidly die over night)
It seemed to start doing it when I got the sleep cover. I feel like that has caused it, but could be co-incidence.
Before I got the sleep cover I could go several months without a charge, but now I find myself needing to charge every couple of weeks.
It is just over 1 year old.

[BatteryPowered]

I have got an old Kobo Glo that does exactly the same. Battery is very old and weak and the charge controller is way out of sync. It does recover some when you let it drain fully and then charge it back up using a slow (<500mA) charger. I actually took mine apart and charged the cell with my proprietary charger, still showed 821mAh out of the 1000mAh it once had. Not bad for many years of service.

When a device is new - like under two years new - it shouldn't act like that. The charge chip is well aware of the Li-Ion discharge cycle and should measure incoming and outgoing energy/amperage to accurately display the SoC - State of Charge.

Sometimes these devices just need a bit of calibration when they get older.

[Pam R]

Thanks again for all the comments. I will do a few more runs of letting the battery drain, take the sleep cover off and see what happens. Currently at 27 hours and the battery is at 47%.

[JSWolf]

Originally Posted by acprinter

My Kobo Clara also does well until it hits 50% and then drops to 0% overnite. I am sticking with my Paperwhite, I like it better anyway.

The Clara was a poor investment.

You like the Paperwhite better? Why?

[JSWolf]

Originally Posted by Fozkas

That is "normal" on the kobos. At least in all that gone through my hands.

Battery is prety good until about 50-40, from there is quite quick to 0

This is not normal.

My guess is it could be due to how the battery has been treated and how often it's gone flat.

[porphyry5]

Originally Posted by porphyry5

Your second point is a possibility so I'm testing it now by deliberately turning it off each evening instead of just letting it sleep. I'll report back again in a couple of days whether it makes a difference.

Now it is starting to look like this is not a problem with my Clara after all, but my use of it. I habitually go to sleep while reading, so the reader is in the bed all night long.

I had Settings 'Automatically go to Sleep' after 10 minutes and "Automatically Power-Off' Never. I've changed 'Automatically Power-Off' to 15 minutes and the device has stopped fully discharging overnight. It's now been running on the same charge for 6 days and is at 62%.

It is kind of annoying to have to Power on every time I use it, but it was also annoying to have to charge the thing every day. But I really can't see any way to pleasantly combine my sleeping habits with Kobo's prominent On/Off button. Wish they'd recess it instead.

[John F]

Originally Posted by porphyry5

Now it is starting to look like this is not a problem with my Clara after all, but my use of it. I habitually go to sleep while reading, so the reader is in the bed all night long.

I had Settings 'Automatically go to Sleep' after 10 minutes and "Automatically Power-Off' Never. I've changed 'Automatically Power-Off' to 15 minutes and the device has stopped fully discharging overnight. It's now been running on the same charge for 6 days and is at 62%.

It is kind of annoying to have to Power on every time I use it, but it was also annoying to have to charge the thing every day. But I really can't see any way to pleasantly combine my sleeping habits with Kobo's prominent On/Off button. Wish they'd recess it instead.

That still seems like abnormal behaviour. My kobo devices are set to never shutdown, and I don't see any quick discharges.

[milady133]

I've this problem sometimes due to problems synchronizing. I have a medium library of Kobo bought books (I haven't checked, but might be about 100~200). I leave wifi on and usually works ok, until suddenly it can't synchronize, and the battery drains in a few hours trying to synchronize the information of t the book I'm reading.
To correct the problem I have to repair my account, and then log off and log on again. I lose the statistics and finished status of my sideloaded books, but I work with databases in my day job, so I've some scripts to return that status quite quickly using a backup (something similar to what the Kobo Touch Extended plugin does).
I should use an account without books with my Kobo and sideload all my books, but usually I take weeks to backup my bought books to Calibre and from time to time there's a book I want to begin reading as soon as it's available, so having it in my Kobo account is convenient. I suppose until the synchronization problem is frecuent I won't bother to create a new account just to register my Kobos.

[Fozkas]

Originally Posted by JSWolf

This is not normal.



My guess is it could be due to how the battery has been treated and how often it's gone flat.

I never let my devices go to 0 unless carelessness on my part (leaving in the drawer for to long).

Besides the kobos (at least mine) always shown that behaviour since new.

[porphyry5]

Originally Posted by John F

That still seems like abnormal behaviour. My kobo devices are set to never shutdown, and I don't see any quick discharges.

It is rather strange, with 80%+ charge on the battery it should run continuously more than 8 hours. I think what happens is it gets bound up in the blankets which depresses the Power button and keeps it depressed, which somehow accelerates the discharge.

Anyway, its nice to know the item is not at fault, but as I can't see any way to guarantee not falling asleep with it on, I'll just have to live with a slow start-up. Thanks for your help on this issue.

[davidfor]

Originally Posted by porphyry5

It is rather strange, with 80%+ charge on the battery it should run continuously more than 8 hours. I think what happens is it gets bound up in the blankets which depresses the Power button and keeps it depressed, which somehow accelerates the discharge.

It's more likely that something is triggering the touch sensor. For the IR based touch, that just needed something touching the screen. For the capacitive based touch, it needs to be something that is detected as a touch. It could be you, or it could be that whatever the blankets are made of do it. If a constant touch on the screen is detected, then it will run the battery down quickly.