iBook G4 battery plummets from 30% to 0% in seconds

Minutes ago, I was doing ordinary Web browsing and sshing when, all of a sudden, the machine shut itself off.
Yeechang Lee wrote on :

Something odd just happened to my almost-new iBook G4 12", which I hope others can shed a light on.

Minutes ago, I was doing ordinary Web browsing and sshing when, all of a sudden, the machine shut itself off. The obvious answer was a drained battery, but a) I was certain it wasn't time (in my experience, the iBook's battery lasts for 4:30, +- 15 minutes, under my normal usage patterns) and b) I hadn't seen any low battery warnings. Besides, the machine wasn't asleep; it was off. So much that neither the power button nor Ctrl-Apple-power button worked.

Fortunately, the power button worked once I attached the power cord. Once logged in again, I found that the battery level had hit 0% or 1% before rising again with the power cord present. XBattery (which I keep running all the time)'s battery level chart says that the charge suddenly spiked from about 30% to 100%, along with two of those little marks above the 100% line that I believe mark reboots, then immediately dropped to 0%/1%..

Any ideas on what happened? The only recent notable change I've done to the system is installing the latest Airport software upgrade through Software Update earlier tonight.

Peter Renzland replied on :

In article slrnc4dpos.oep.ylee@redacted.invalid, Yeechang Lee wrote:

Something odd just happened to my almost-new iBook G4 12", which I hope others can shed a light on.

Hey another slrn user :-)

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

Let us know how it works.

-- Peter

Yeechang Lee replied on :

Peter Renzland phr0206@redacted.invalid wrote:

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

While your utility looks interesting, I'm skeptical of the merits of another calibration given that 1) I did a trickle calibration right after unpacking the iBook a few weeks ago, and 2) yesterday's forced shutoff appeared as another calibration to the battery, if of a rougher kind.

Proximus Centauri replied on :

Peter Renzland phr0206@redacted.invalid wrote in message news:smC1c.13261$JZ6.360826@redacted.invalid...

In article slrnc4dpos.oep.ylee@redacted.invalid, Yeechang Lee wrote:

Something odd just happened to my almost-new iBook G4 12", which I hope others can shed a light on.

Hey another slrn user :-)

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

Let us know how it works.

-- Peter

I had a similar problem w/ my powerbook 1400. The battery would "hold a charge", but the system forced it to sleep after 5 minutes of use. Out of curiosity, i used an ampmeter to see if the battery was truly dead- and infact it had plenty of juice. Over the course of a week or so- i forced conditioned it by totally draining the battery (i actually wired it to run my cordless drill, and amazingly it ran the drill for about 5 hours of constant use before it ran out of juice) after a few sessions with the drill and then recharging it- it has worked beter than it ever has before (i get about 4.5 hours of use now). However, i dont know if i would recommend doing this. I really didnt care if i totally destroyed my battery- so take it for what it's worth....

Peter Renzland replied on :

In article slrnc4enj6.oep.ylee@redacted.invalid, Yeechang Lee wrote:

Peter Renzland phr0206@redacted.invalid wrote:

I suggest you do a trickle calibration. Get www.renzland.org/batmon and look at the comments.

While your utility looks interesting, I'm skeptical of the merits of another calibration given that 1) I did a trickle calibration right after unpacking the iBook a few weeks ago, and 2) yesterday's forced shutoff appeared as another calibration to the battery, if of a rougher kind.

Interesting. If it were I, I would run batmon in a terminal window (with much scrollback), or else in the background tee'd to a log file. That way you can tell what happened when, quantitatively.

There are other programs - XBattery is very nice.

Question: what is your capacity? I don't recall that you told us. (Before and after yesterday's event)

What causes it? I don't know, but I do know that load surges can trigger it, and that discharging at low load can ameliorate it. What I do is run batmon when on battery, which tells me the load and audibly warns me of sudden changes.

I also keep the display low (1/16), and turn off airport when I don't need it. When unplugged I like to keep the load under .750A.

IOW, I think of batmon as a monitor tool, rather than a calibration tool.

-- Peter

Peter Renzland replied on :

Proximus Centauri wrote:

Peter Renzland phr0206@redacted.invalid wrote

In article slrnc4dpos.oep.ylee@redacted.invalid, Yeechang Lee wrote:

Something odd just happened to my almost-new iBook G4 12", which I hope others can shed a light on.

Hey another slrn user :-)

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

Let us know how it works.

-- Peter

I had a similar problem w/ my powerbook 1400. The battery would "hold a charge", but the system forced it to sleep after 5 minutes of use. Out of curiosity, i used an ampmeter to see if the battery was truly dead- and infact it had plenty of juice. Over the course of a week or so- i forced conditioned it by totally draining the battery (i actually wired it to run my cordless drill, and amazingly it ran the drill for about 5 hours of constant use before it ran out of juice) after a few sessions with the drill and then recharging it- it has worked beter than it ever has before (i get about 4.5 hours of use now). However, i dont know if i would recommend doing this. I really didnt care if i totally destroyed my battery- so take it for what it's worth....

I don't suppose you made a note of the battery's capacity before and after? I mean the capacity as estimated by the software/firmware, and indicated ioreg. (or XBattery, battery, or batmon),

-- Peter

Yeechang Lee replied on :

Peter Renzland phr0206@redacted.invalid wrote:

Question: what is your capacity? I don't recall that you told us. (Before and after yesterday's event)

4.611 before, 4.5xx after. Not a huge change, but a chance nonetheless.

Peter Renzland replied on :

In article slrnc4evvi.n0g.ylee@redacted.invalid, Yeechang Lee wrote:

Peter Renzland phr0206@redacted.invalid wrote:

Question: what is your capacity? I don't recall that you told us. (Before and after yesterday's event)

4.611 before, 4.5xx after. Not a huge change, but a chance nonetheless.

I would have expected 10 times as much difference, if it dropped from 30% to empty.

BTW, I don't suppose you noticed any discontinuity while charging? What I have seen is that a discharge jump is matched by an equal charge jump at the other end, i.e. charges linearly to 70% and then jumps to full.

-- Peter

John Johnson replied on :

In article slrnc4enj6.oep.ylee@redacted.invalid, Yeechang Lee ylee@redacted.invalid wrote:

Peter Renzland phr0206@redacted.invalid wrote:

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

While your utility looks interesting, I'm skeptical of the merits of another calibration given that 1) I did a trickle calibration right after unpacking the iBook a few weeks ago, and 2) yesterday's forced shutoff appeared as another calibration to the battery, if of a rougher kind.

Have you called Apple? This iBook is under warrantee, and that includes your battery. You're still in the 90 day free-call period (offered in the USA, at least), so it's no charge.

IMO, call Apple, make a full back-up of the drive, and see what they say. I also strongly recommend AppleCare to all iBook and PowerBook owners.

This isn't to say that the diagnostic that Peter R. is talking about isn't useful, but it looks to me like this pretty clearly falls under the warrantee conditions, and I'm lazy enough to let someone else deal with it, if I can. ;-)

Peter Renzland replied on :

John Johnson wrote:

In article slrnc4enj6.oep.ylee@redacted.invalid, Yeechang Lee ylee@redacted.invalid wrote:

Peter Renzland phr0206@redacted.invalid wrote:

I suggest you do a trickle calibration.

Get www.renzland.org/batmon and look at the comments.

While your utility looks interesting, I'm skeptical of the merits of another calibration given that 1) I did a trickle calibration right after unpacking the iBook a few weeks ago, and 2) yesterday's forced shutoff appeared as another calibration to the battery, if of a rougher kind.

Have you called Apple? This iBook is under warrantee, and that includes your battery. You're still in the 90 day free-call period (offered in the USA, at least), so it's no charge.

IMO, call Apple, make a full back-up of the drive, and see what they say. I also strongly recommend AppleCare to all iBook and PowerBook owners.

This isn't to say that the diagnostic that Peter R. is talking about isn't useful, but it looks to me like this pretty clearly falls under the warrantee conditions, and I'm lazy enough to let someone else deal with it, if I can. ;-)

Something just occurred to me . . .

If you really did a trickle calibration on a brand new battery, you will have calibrated it based on slow discharge, which is to say that the estimate of the battery's capacity represents a slow discharge pattern.

So, it's quite possible that the battery's capacity was overestimated. How does the capacity compare with what it was at the very start, and what it is rated to be?

In any case, if it went from 30% to nothing there would appear to be a problem, and Apple should be able to help you.

(They'll probably start by saying -- calibrate.)

-- Peter

Yeechang Lee replied on :

Peter Renzland phr0206@redacted.invalid wrote:

BTW, I don't suppose you noticed any discontinuity while charging? What I have seen is that a discharge jump is matched by an equal charge jump at the other end, i.e. charges linearly to 70% and then jumps to full.

No discontinuities whatsoever; consistently a smooth curve whose slope smoothly declines as the charge approaches 100%.

Yeechang Lee replied on :

John Johnson null@redacted.invalid wrote:

Have you called Apple? This iBook is under warrantee, and that includes your battery. You're still in the 90 day free-call period (offered in the USA, at least), so it's no charge.

IMO, call Apple, make a full back-up of the drive, and see what they say. I also strongly recommend AppleCare to all iBook and PowerBook owners.

I will certainly contact Apple should this happen again, but in the meanwhile am content to see if it's a one-time thing.

Yeechang Lee replied on :

Peter Renzland phr0206@redacted.invalid wrote:

If you really did a trickle calibration on a brand new battery, you will have calibrated it based on slow discharge, which is to say that the estimate of the battery's capacity represents a slow discharge pattern.

So, it's quite possible that the battery's capacity was overestimated.

I've used the system often enough since the initial calibration a few weeks ago that I am confident this isn't the issue. That is, I really do get 4:30, +- 15 minutes, off a full charge, complete with utterly smooth drain curves in XBattery, under my usual usage patterns. I haven't drained the battery to 0% since said calibration, but have seen 10-15% several times.

Peter Renzland replied on :

In article slrnc4f7jd.n0g.ylee@redacted.invalid, Yeechang Lee wrote:

Peter Renzland phr0206@redacted.invalid wrote:

If you really did a trickle calibration on a brand new battery, you will have calibrated it based on slow discharge, which is to say that the estimate of the battery's capacity represents a slow discharge pattern.

So, it's quite possible that the battery's capacity was overestimated.

I've used the system often enough since the initial calibration a few weeks ago that I am confident this isn't the issue. That is, I really do get 4:30, +- 15 minutes, off a full charge, complete with utterly smooth drain curves in XBattery, under my usual usage patterns. I haven't drained the battery to 0% since said calibration, but have seen 10-15% several times.

I may be wrong, but I suspect that the former would be better than the latter.

Depends on your usage pattern, of course. Batmon is good for minute monitoring and logging.

Latest version speaks to you (if your computer is on speaking terms) to alert you to battery conditions.

I'm very surprised that you report that a 30% drop in charge resulted in no more than a 2% adjustment in capacity.

In every case that I've seen, the precise difference was adjusted to get the new capacity. Thus, if it dropped from .400Ah to empty, it would reduce the capacity by .400Ah. And if it ran on empty for 30 minutes at 500mA, it would add 250mAh to the capacity.

Since you said you want to keep an eye on it, perhaps you might do something like batmon | tee batmon.log and then, when there's a problem, you can post the excerpt from the log.

Or else just run it in a terminal window with unlimited scrollback.

-- Peter

Many years ago, I drove to Kingston in my pretty new car. Straight freeway, blue skies, full tank, so I wanted to see how long it would take if I floored the gas pedal. Just before Kingston, the car just stopped running, for no apparent reason. I called the Auto Club, and after some time it was determined I had run out of gas! At the speed I was going it simply consumed way more gas than normal. Battery consumption might be like that.

az_dude replied on :

I had this happen awhile ago on my iBook G3. It was NOT a 1-time thing... it happened every single time I got down to 37%.

Also, when charging, it jumped from about 63% to 100%.

I tried recalibration. When that didn't work, I just did some continuity analyses with XBattery (which verified & documented my battery patterns for the Apple Geniuses to see later).

I was totally unable to fix it myself, but when I took it to the Apple Store, the genius just handed me a new battery that worked fine. Nifty!

-Jerrod

"Yeechang Lee" ylee@redacted.invalid wrote in message news:slrnc4dpos.oep.ylee@redacted.invalid

Something odd just happened to my almost-new iBook G4 12", which I hope others can shed a light on.

Minutes ago, I was doing ordinary Web browsing and sshing when, all of a sudden, the machine shut itself off. The obvious answer was a drained battery, but a) I was certain it wasn't time (in my experience, the iBook's battery lasts for 4:30, +- 15 minutes, under my normal usage patterns) and b) I hadn't seen any low battery warnings. Besides, the machine wasn't asleep; it was off. So much that neither the power button nor Ctrl-Apple-power button worked.

Fortunately, the power button worked once I attached the power cord. Once logged in again, I found that the battery level had hit 0% or 1% before rising again with the power cord present. XBattery (which I keep running all the time)'s battery level chart says that the charge suddenly spiked from about 30% to 100%, along with two of those little marks above the 100% line that I believe mark reboots, then immediately dropped to 0%/1%..

Any ideas on what happened? The only recent notable change I've done to the system is installing the latest Airport software upgrade through Software Update earlier tonight.

-- Read my Deep Thoughts @redacted.invalid URL:http://www.ylee.org/blog/ PERTH ----> * 00:09:02 up 11 days, 2:09, 11 users, load average: 2.32, 2.34, 1.91 171 processes: 167 sleeping, 3 running, 1 zombie, 0 stopped CPU states: 16.7% user 5.6% system 77.6% nice 0.0% iowait 0.0% idle