Forma Sudden Battery Drain Syndrome

[alanfw]

Forma is the biggest heap electronic shit I have ever paid more than $100 for! (Either that or Kobo's software engineers are the most incompetent morons to ever write firmware.)
I closed my Forma this morning at about 80% battery. This evening it wouldn't wake up. I had to plug it in and it showed zero battery. This is a replacement that is less than a year old when the Forma I bought died after less than a year. My partner's Forma died after 14 months.
It's a real shame because when I bought it and it was working I loved it.

[enuddleyarbl]

Well, this is worrying. My one year old Sage replacement for my old 1-1/2 year old Forma just suddenly shut off with an empty battery. No notification that the battery was low. Plugged it in and when it started up, the battery was at 1%. Hopefully, it's just a fluke. But, I'll have to keep an eye on it.

[Sirtel]

Originally Posted by enuddleyarbl

Well, this is worrying. My one year old Sage replacement for my old 1-1/2 year old Forma just suddenly shut off with an empty battery. No notification that the battery was low. Plugged it in and when it started up, the battery was at 1%. Hopefully, it's just a fluke. But, I'll have to keep an eye on it.

Weird. My Sage is over two years old, used basically every day and has never done this. Hopefully it's just a glitch.

[Aleron Ives]

The battery meter is notoriously unreliable. Unless you deep cycle it periodically, it will report numbers that are farther and farther away from reality.

[Quoth]

Or it could be faulty LiPoly cell. At least the cell can easily be replaced on a Sage.

[compurandom]

or it could have gotten stuck syncing with wifi on or forever searching a pdf chewing cpu.
Both of those will drain battery. Reboot fixes both.

[John F]

Originally Posted by Aleron Ives

The battery meter is notoriously unreliable. Unless you deep cycle it periodically, it will report numbers that are farther and farther away from reality.

What do you consider a "deep cycle" and how periodically? I tend to go down to 20-40% and charge to 100%, and haven't had any strange battery meter behavior.

[compurandom]

Originally Posted by John F

What do you consider a "deep cycle" and how periodically? I tend to go down to 20-40% and charge to 100%, and haven't had any strange battery meter behavior.

Deep cycle for typical lithium battery chemistry is 10% or below. Basically, it's where your device says "charge me now, I'm shutting off". Most manufacturers recommend doing this every 6 months, but it shortens your battery life significantly, so I'd recommend doing it on purpose no more than once a year.

If you are already bringing it down to 20% (which is safe and probably doesn't hurt the battery life too much), then you may be slowly losing the remaining 10% in the meter. You might not notice for a year or two (or three)...at which time you should go lower.

[enuddleyarbl]

I always let the battery get down to that 10% warning point. Wifi is off. No PDFs. Just the same use as always. With the Forma, battery drain was normal until it got a bit low (as noted earlier in this thread). I'll keep watch on it this cycle and see how it goes.

[fogice]

I keep wifi off. My Libra 2 recently went into high power drain mode, I could almost see the battery drain. I had just side loaded new books to the device. I restarted the Libra, and it was fine after that. Hadn't experienced a high drain event for months before that.

[enuddleyarbl]

Oops. I forgot to mention I've been rebooting every couple of days recently (so I can sideload a book from Calibre without corrupting the database).

[Sirtel]

Originally Posted by enuddleyarbl

I always let the battery get down to that 10% warning point. Wifi is off. No PDFs. Just the same use as always. With the Forma, battery drain was normal until it got a bit low (as noted earlier in this thread). I'll keep watch on it this cycle and see how it goes.

How bright is your frontlight? The Sage seems not to like it when the light is on a high level.

[Aleron Ives]

Originally Posted by John F

What do you consider a "deep cycle" and how periodically? I tend to go down to 20-40% and charge to 100%, and haven't had any strange battery meter behavior.

I usually keep the charge between 25 - 85%, and after a few months the battery meter has started to lose its calibration in the past, saying that the battery is suddenly empty. It seems that if you don't drain the battery to the single digits every few months, the meter no longer reports the actual charge, and then when the voltage drops, you get the "sudden battery drain" symptom of the meter jumping from 30% to single digits over a matter of minutes.

[enuddleyarbl]

Originally Posted by Sirtel

How bright is your frontlight? The Sage seems not to like it when the light is on a high level.

The frontlight is set to 38%.

[Sirtel]

Originally Posted by enuddleyarbl

The frontlight is set to 38%.

Mine is 9% (when I require a higher level, I use my Libra 2). That said, I have no idea if 38% is too high for the Sage or not; but people have had battery issues with the light over 50%.