K5 Can a Kindle Touch battery die without triggering the "Critical Battery" error?

[WaseemAlkurdi]

My Kindle Touch has died all of the sudden, even though its battery was at 100%. (I was doing some "dev" experimenting, but I took a break and used it as a normal Kindle in the few days prior to this because life took over)
- Hard reboots cause it to either restart and freeze at the Kindle Tree/Boy logo, or not restart at all, or at the progress bar (once or twice).
- It actually managed to fully boot once or twice (and the status bar battery meter reads 100%), but it freezes after a few moments.
- Booting to USB HID results in the correct USB HID device showing up, and imx_usb could flash it, but it won't reboot to the selected mode (diags/fastboot) (save for one time when it actually did boot to diags).
- Note that the Kindle Touch has been in my possession for only two weeks. Prior to that, it was shipped by air mail, and it arrived with a "plug battery in" image (no text). (Not sure how they do it, but mail carriers do something to discharge batteries to zero % prior to shipping).
- I have charged it for four hours back then. I planned on a 24-hour charge, but since it showed 100%, I thought that four hours was enough.
Note that when I cracked it open, I noticed that it was on its original battery with a date of 2011.
- It's now on a wall charger.
Do you think it's simply an aging battery or a dead one?

[knc1]

Originally Posted by WaseemAlkurdi

- - - - - - -

Do you think it's simply an aging battery or a dead one?

I do not follow what the difference would be.

Freeze the Kindle (with battery) before wall charging.
You will want to "wrap" the Kindle so that it does not gather moisture (condensation) when you take it out of the freezer.
Note that it may take more than a single "freeze/charge" cycle.

Whatever the case, aging or dead, buy a new battery.

[WaseemAlkurdi]

Originally Posted by knc1

I do not follow what the difference would be.

What I meant by "dead battery" is a completely flat battery (0%) that, for some reason, reports 100%. (Possibly bad calibration or a side effect of being emptied before air shipping, and could be somehow refilled), and by "aging battery", a battery that had died with age and/or use, beyond safe repair (unsafe repair = replacement of the individual cells).

Freeze the Kindle (with battery) before wall charging.

It's been charging for seven hours or so since my last post (while I was out and hopefully distracted), but I've just returned, to see that nothing had changed in the meanwhile (except that the orange LED is now off).
I think I'm going to do just this ... but for how long do you suggest I freeze it? Minutes or hours?

You will want to "wrap" the Kindle so that it does not gather moisture (condensation) when you take it out of the freezer.

I think a ziploc bag would do, but how about a handful of rice in the same bag while in the freezer? (Rice absorbs moisture, but would it absorb it while in the freezer?)

Whatever the case, aging or dead, buy a new battery.

Cool, but I paid $20 (+$7 for shipping) for this Kindle Touch, while a battery from China costs $15 with shipping. It's roughly the price of a Kindle ... except that one can't gamble with buying another used Kindle now that this one turned out to be a lemon (did it?)

[knc1]

I usually freeze mine over night.
I lightly wrap a micro-fiber towel around the Kindle the entire time (both freezing and thawing).

It isn't the freezer step that collects condensation, it is the removal to room air (which is done while on the wall charger).


The light is computer controlled.
Is your Kindle computer operating normally?
Duh...
Ignore the light.


PS: The above works for as new as PW3 (I haven't deep discharged anything newer (yet) ).

[WaseemAlkurdi]

Originally Posted by knc1

I usually freeze mine over night.
I lightly wrap a micro-fiber towel around the Kindle the entire time (both freezing and thawing).

I'm going to do it ... but I'm still worried, especially that it has a Lithium-Polymer battery.

It isn't the freezer step that collects condensation, it is the removal to room air (which is done while on the wall charger).

Drone people, heavy users of Li-Po, say that one shouldn't connect a Li-Po to a charger while cold.
But it's all hearsay anyhow, and it isn't like I really have a whole lot of options aside from the good ol' freeze.

The light is computer controlled.
Is your Kindle computer operating normally?
Duh...
Ignore the light.

I know (I played with the LED tests in diags and I believe they have a node under /dev), but I guessed that since the Kindle is too "weak" to even read the eMMC and get code to let software operate the LED, it might be, for once, reliable.

PS: The above works for as new as PW3 (I haven't deep discharged anything newer (yet) ).

If I read you correctly, could the issue be, no matter how remotely, a deep-discharged battery?
Or, is there any hope at all?

[knc1]

The Amazon "wall charger" is not a "charger" in the sense you are reading about them. They are only a source of 5 volt dc.


You will not be connecting the "charger" to the battery, you will be connecting it to the USB connection on the Kindle.
Inside, between the dc power and the battery is a fairly sophisticated power management circuit.
"fairly" does not fully deal with the things that can happen to a Li-po battery.
Which is the reason behind the low level temperature use - it "tweaks" the battery management system to correctly charge an over-discharged battery.


PS: The RC model world and the original RC drones once upon a time used "bare" Li-po batteries.
Thus the warning you have read about.


At least in the USA, all Li-po batteries sold in this country have included at least minimal battery management built in.
The Kindle has such controlled batteries PLUS the Freescale power management system (which you are tweaking).


Relax. Your ice cream will not be blown up by the Kindle.

[WaseemAlkurdi]

Originally Posted by knc1

The Amazon "wall charger" is not a "charger" in the sense you are reading about them. They are only a source of 5 volt dc.


You will not be connecting the "charger" to the battery, you will be connecting it to the USB connection on the Kindle.
Inside, between the dc power and the battery is a fairly sophisticated power management circuit.
"fairly" does not fully deal with the things that can happen to a Li-po battery.
Which is the reason behind the low level temperature use - it "tweaks" the battery management system to correctly charge an over-discharged battery.


PS: The RC model world and the original RC drones once upon a time used "bare" Li-po batteries.
Thus the warning you have read about.


At least in the USA, all Li-po batteries sold in this country have included at least minimal battery management built in.
The Kindle has such controlled batteries PLUS the Freescale power management system (which you are tweaking).

Ah ... actually, that's way more reassuring!

Relax. Your ice cream will not be blown up by the Kindle.

Actually, I fear for the loss of the Kindle more than the ice cream!

P.S. Sometimes, it racks up enough power to get me to diags. Does it charge (better/quicker/anything at all) while in there?
I also noticed the option H) Adjust battery while there.
It shows the battery percentage and whether it's acceptable for "shipping mode".
When the battery level is < 75%, it reports "charging" and the rate (at which it does?)
However, when the battery is more than that, the orange LED turns off as long as I'm on that page, and the page reports: Charger Mode: Off.
Any thoughts?

[NiLuJe]

From my (extremely limited) experience, charging is wonky as hell when in diags. An unplug/replug may help, but it generally tends to discharge more than anything else .

[knc1]

Does it charge (better/quicker/anything at all) while in there?

No, it only gets colder.
You only charge it AFTER REMOVING (while it is still cold) from the freezer.


If you are uncomfortable about this process, please do not do it.
Never do something you are unsure of.

[WaseemAlkurdi]

Originally Posted by NiLuJe

From my (extremely limited) experience, charging is wonky as hell when in diags. An unplug/replug may help, but it generally tends to discharge more than anything else .

Leaving it in diags, I did notice that too. Yes, it does charge for a while (about 4% or so from that Battery Info screen), but then it freezes again.
I initially thought it would be faster because the damn thing actually managed to reach diags (but not main).

[WaseemAlkurdi]

Note that throughout this ordeal, the battery reports > 50% the whole time.
Is that fine for a heavily-discharged battery as opposed to a dead one?

[WaseemAlkurdi]

Originally Posted by knc1

No, it only gets colder.
You only charge it AFTER REMOVING (while it is still cold) from the freezer.


If you are uncomfortable about this process, please do not do it.
Never do something you are unsure of.

I meant "while in diags" not "while in the freezer".
Anyhow, I am uncomfortable about this, but (a) the rationale behind it is convincing, and (b) what else is there to do, apart from buying a new battery for no reason at all?

[knc1]

Originally Posted by WaseemAlkurdi

I meant "while in diags" not "while in the freezer".
Anyhow, I am uncomfortable about this, but (a) the rationale behind it is convincing, and (b) what else is there to do, apart from buying a new battery for no reason at all?

I suppose it depends in part on how long you have been reading along with this forum.

There was a member here that wanted to run a "current hazard conditions" report on DXG devices.
Snow hazards.
Alpine area ski resorts.
Outdoors.
In an area that **might** be above freezing in the middle of summer.

The devices where reported to be working quite well, even with their original battery.
I had to wonder about that one day, with a pile of Kindles showing "empty" battery icons looking at me.

And having a bit of electronics background (about 60 years of it) I wondered if the Amazon/Lab126 people had checked their designs at extremes of temperature.

Putting a Li-Ion battery in the fire while recharging it did not seem to be a good idea.

Which lead to the only choice, test the result of running the Kindles at freezing conditions.
Mostly just a matter of luck on my part.


PS: Avoid "diags" when recharging if you can.

[WaseemAlkurdi]

IT WORKED!
I can't ever, ever thank you enough!

I basically stuck it in a fridge for just half an hour (I couldn't find a microfiber towel around me, so I wrapped it with a regular towel, but I noticed condensation on the screen, so I pulled it at half an hour).

It worked! The device sat there for about five seconds, then suddenly gave a couple of very soft hisses, like the ones you'd get with a damaged wall charger, except that it was coming out of the Kindle, not the charger, then the screen reflashed and displayed the "low battery" icon (not "Critical battery" with text, but a low battery icon with a picture of a USB cable underneath).

A minute or so, it powered up. The LCD was a bit slower (and I still feel that it is slow, but never mind), but it started charging from 1%.

I noticed that for some reason, KUAL and Collections Manager now feature the "cover" icons that I had seen in the decompiled version. Before that, it was only text covers. Weird, right?

An hour or so later, it froze again. I couldn't read the percentage (because it was plugged in, so the battery meter did not show the percentage), and a reboot caused the ominous freeze. I threw it in the freezer again. This time however, I wrapped it in soft cloth, and that did help (no moisture formed at all).

At first, it didn't boot, but just before I gave up, it worked. It resumed charging at 80% (not a good sign), but dunno, it did not freeze again as of the time of writing, albeit the LCD is a little slow (or is it?) (Edit: nope, seems to be my imagination)

I might edit the Kindle Touch Hacking page in the Wiki to add this notice. Do you think it's a good idea?

I still believe that the battery is toast though because it froze again at 80%. Do you agree? Is it worth it, in your opinion, to buy a battery that costs as much as a Kindle?

(EDIT 2: Froze again. I'm going to freeze it for eight hours -overnight-, then charge it again).

Originally Posted by knc1

I suppose it depends in part on how long you have been reading along with this forum.

A couple of months ... maybe half a year now.

There was a member here that wanted to run a "current hazard conditions" report on DXG devices.
Snow hazards.
Alpine area ski resorts.
Outdoors.
In an area that **might** be above freezing in the middle of summer.

The devices where reported to be working quite well, even with their original battery.
I had to wonder about that one day, with a pile of Kindles showing "empty" battery icons looking at me.

And having a bit of electronics background (about 60 years of it)

And you call that "a bit" of background?

I wondered if the Amazon/Lab126 people had checked their designs at extremes of temperature.

Probably not, due to the Kindle being super-cheap and disposable. They might cut corners. They didn't even bother to lock the bootloader, even though it costs them nothing but a fuse. (I know, I'm going to keep quiet and not give them ideas )

Putting a Li-Ion battery in the fire while recharging it did not seem to be a good idea.

It is a good idea for a fireworks show though.

Which lead to the only choice, test the result of running the Kindles at freezing conditions.
Mostly just a matter of luck on my part.

No, not luck. Call it serendipity if you want, but not pure luck. It's not like you mistook the Kindle for a can of beer when you stowed it in that freezer

PS: Avoid "diags" when recharging if you can.

Noted ... but what about fastboot? Geekmaster once said that Kindles charge faster there. Do you agree?

[knc1]

geekmaster is no longer with us.
But you can trust anything that he ever wrote here.