Noticeable Battery Drain on KOReader - Kobo Clara HD

[garlicshampoo]

Hello all, I have a 2 months old Kobo Clara. I installed KOReader two days ago and was very happy with it except for the fast, noticeable battery drain. I've done my research but haven't found an answer.

Within two days of installation my battery drained 20%, a rate I've never seen before while being on the stock reader. The overnight drain (observed after the first night) was 3% which is significant given the overall battery performance on the device. I just switched back to the stock reader the second night and battery level stays the same.

For context: 1-I'm usually able to use the device for a few weeks before charging it. I barely notice the battery dropping, and it certainly does not drop 10% or more in a day. 2-I set up KOReader using the one-step installation script. When I first set it up I tinkered around with some customization which might have required more battery, but I stopped doing that after noticing the fast drain and it still didn't change things. 3-The battery drain happens regardless of the book I'm reading, so it's unlikely due to one "bad" book. I read almost exclusively epub. 4-Some answers I read in other threads mention that the battery gauge on Kobo devices is unreliable, but I've found it accurate so far.

Is this a common issue? What can I do to fix this? I really want to stick with KOReader if that's possible. I'm being spoiled by the page turn speed and calendar view of the reading stats, among other neat features.

[NiLuJe]

We don't suspend while reading. Nickel does. There's (part of) your page-turn speed trade-off .

(I am somewhat vehemently *against* implementing something like that, because I *like* that behavior. That said, the framework is there, because it's implemented on PocketBook. This is possibly a fairly deep rabbit hole with a lot of potentially bad interactions, though, but patches welcome ).

That said, that still sounds like a much more significant delta than it ought to be (despite what I said above, I usually don't notice a significant difference. Then again, I haven't read in Nickel in quite a while now).

And, yeah, don't trust the battery gauge. Like, at all.

[garlicshampoo]

Understood what you just said, and I take it to mean that there's some trade-off for the faster speed I'm getting in KOReader.

If we don't go by the battery percentage, how should we decide when to charge the device? I usually do it when the battery level drops below 20% (I inherit this habit from charging my smartphone, though I'm sure the two batteries are different). Do you only charge it when the device is completely out of battery and does not turn on anymore? Or do you use a different gauge?

I'd expected for KOReader to take up more battery than Nickel but didn't expect such significant drop. I'll give it a few more tries before removing it.

[church mouse]

@garlicshampoo

It may not be relevant to your issue, but I found that going into the KoReader settings and setting KoReader to ignore all sleepcover events helped with my KoReader battery drain.

[NiLuJe]

I charge when necessary or practical, whatever that may be (loading books, working on stuff, or just noticing that I might need to use it for extended periods of time soon, etc), so it's never been actively annoying one way or another.

The actual percentage shown is fairly orthogonal to all of that: what/where/how long I intend to use the device(s) isn't .

[Frenzie]

Originally Posted by garlicshampoo

If we don't go by the battery percentage, how should we decide when to charge the device? I usually do it when the battery level drops below 20% (I inherit this habit from charging my smartphone, though I'm sure the two batteries are different). Do you only charge it when the device is completely out of battery and does not turn on anymore? Or do you use a different gauge?

The battery indicator is a bit nonsense on most (all?) of these devices, except in the most generic terms. Maybe it's different on the Clara, but on my H2O it can easily drop to 90% or 80% super quickly, drop only a percent or two per day from 80-60, drop somewhat slowly to about 30% and then it'll display 20% for a little while but the device will be dead any moment (i.e., 20% means what you think 1% means). The important thing is that it lasts a couple of weeks or more on a charge so it doesn't really matter. NB This is not KOReader specific, you see the exact same thing in Nickel, unless they've implemented an adjusted curve these days to make it seem more gradual.

Definitely charge it at any value under 50% if you intend to use it all weekend without easy access to a charger just in case, and somewhere above 30% for "regular" use.

I'm not sure why you'd expect KOReader to drain more — it sure doesn't for me. If true that would mean either some kind of bug related to your device or how you use it, or Nickel's managed to greatly up their energy efficiency.

PS Have you set your wifi to auto turn off? If it's always on vs only on when requested that could easily explain a big difference.

[Alan_S]

Originally Posted by garlicshampoo

If we don't go by the battery percentage, how should we decide when to charge the device?

By experience?

You see I have two devices. On my H2O, when you hit 40% or lower, you know you have to charge it. On KA1, you can still read for hours when it hits 0%.

It's just trustworthy like that. Believe it or not.

[Frenzie]

Much more succinct and what I should've written.

[JSWolf]

Originally Posted by Alan_S

By experience?

You see I have two devices. On my H2O, when you hit 40% or lower, you know you have to charge it. On KA1, you can still read for hours when it hits 0%.

It's just trustworthy like that. Believe it or not.

Odd. I don't have to charge wen I hit 40%. I usually charge when I hit in the 30% range.

[Alan_S]

Originally Posted by JSWolf

Odd. I don't have to charge wen I hit 40%.

This is the point I tried to make.

It really depends on your device. You should try and see when device will shut down.

That's how I know how long I still can read when it's "0%". As I kept reading...

[Frenzie]

I don't mean to negate the point that you should get to know your own device, but are you guys even saying anything different than each other? Even if you don't "have to" charge at 40% you probably want to do so at the next opportunity.

[JSWolf]

I usually charge at 20% when I get a warning about low battery or if I might need to have more charge then I currently do.

[Alan_S]

Originally Posted by Frenzie

Even if you don't "have to" charge at 40% you probably want to do so at the next opportunity.

Yes and no.

On my H2O I have to charge it, and battery stays for a long time in high percentages, and very short time in the low ones.

But, my KA1 is quite the opposite, it stays for a short time in high percentages, but for a long time in low percentages.

On KA1 (at least mine) I have days of reading when I hit 40%. So, if I'm not going somewhere where I don't have access to power for days, I just wait it to hit 10%, as I know I still have about 2 or 3 days of reading time.

On the other hand, whenever I know I'll be away for days from power, I charge, no matter what.

Here I also have to say that my H2O works two times longer than my KA1.

[Frenzie]

Yeah, but we're talking about the H2O, not the KA1.

[garlicshampoo]

Thanks everyone for the responses on the battery.

The reason I'm asking the seemingly obvious question of when to charge and how to gauge a device's battery independent of its battery gauge, is because my Clara does a very good job of tracking that, at least for now. Battery does not dip more than 3% daily (and that's with extensive reading in a day), stays consistent overnight, and overall finishes one charge after 2-3 weeks.

This matches with the typical usage experience for Kobo devices, so I was quite surprised to learn there are many devices with unreliable battery gauge. That said I will keep this in mind and next time will read until the device shuts down to see how long it really lasts.

I'm unfortunately switching back to Nickel for now since battery does drain much to quickly to my liking (given that I still trust the gauge on my Clara) and I need to save vocabulary (a beta feature on Nickel). I have Wifi and autosleep events turned off, and that still doesn't help.