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mrmister · Jul 12, 2003, 05:11 PM

Title says it all--and by using XBattery I can see that this is not a phantom effect, but batteries do indeed stop charging and the OS goes into trickle mode somwhere above 95%, seemingly at random. This happens periodically on every portable I've seen.

Anyone know why this happens? Is there anyway to "wakeup" the battery manager so it knows to let the battery fill a little more?

Musti · Jul 12, 2003, 05:48 PM

Originally posted by mrmister:
Title says it all--and by using XBattery I can see that this is not a phantom effect, but batteries do indeed stop charging and the OS goes into trickle mode somwhere above 95%, seemingly at random. This happens periodically on every portable I've seen.

Anyone know why this happens? Is there anyway to "wakeup" the battery manager so it knows to let the battery fill a little more?

It is a new feature to get more charge-recharge cycles from a Li-Ion battery (and "trickle" is the correct word). Once the level drops below 95%, charging starts to top it up to 100%. Otherwise, for slight interruptions the Power Manager has to charge the battery even if it's 99%.

geekwagon · Jul 12, 2003, 06:11 PM

And also, even on a full charge cycle, the charge slows to a trickle once it hits 95%. It is easier on the battery that way. I notice my iPod does this too, it takes about an hour to charge 90% of the way, and 2 hours to do that last 10%.

When I know I want to be charged to 100% for some reason, I usually will just disconnect from the power for a few minutes until I hit 94% and then plug it back in. That way you will get charged back up to 100% again.

mrmister · Jul 12, 2003, 09:33 PM

Well, that's a pretty good reason. Thanks.

GlobalNomad · Jul 12, 2003, 10:27 PM

I usually will just disconnect from the power for a few minutes until I hit 94% and then plug it back in. That way you will get charged back up to 100% again. [/B]

I don't think that is such a good idea.

tonewheel · Jul 12, 2003, 10:30 PM

Already covered numerous times. Do a search.

geekwagon · Jul 12, 2003, 10:37 PM

Originally posted by GlobalNomad:
I don't think that is such a good idea.

Why not? Like I said, I only do it when I am going somewhere and I know I would like to have 100% of the battery available to me. It's not like I do it dozens of times a week.. maybe once or twice a month.

Musti · 11:08 PM

Originally posted by tonewheel:
Already covered numerous times. Do a search.

Already answered. Too late. Thanks for the friendly advice, though.

Musti · Jul 12, 2003, 11:09 PM

Originally posted by geekwagon:
Why not?

...because it defeats the whole purpose of this charge mechanism.

mrmister · Jul 13, 2003, 03:20 AM

"Already covered numerous times. Do a search."

Ah, the lonely cry of the Spotted Grouse.

tooki · Jul 13, 2003, 09:18 PM

Geekwagon, what you're doing is completely pointless.

Each battery has a microcontroller inside it that talks to the power manager inside the PowerBook. It knows that it's just at 94%, and won't start a whole start-to-finish charge cycle. It'll just trickle it up to 100%.

The power manager combined with the "smart" batteries mean that, as far as you are concerned, it works like a gas tank in a car: when you go to fill up, the pump pumps till it's full. But unlike with a gas pump, there is no way to wiggle the nozzle to get a couple more drops in.

tooki

GlobalNomad · Jul 13, 2003, 09:33 PM

Originally posted by tooki:
there is no way to wiggle the nozzle to get a couple more drops in
tooki

LOL this is actually also a bad thing. If you take a corner fast the gas comes out. Volvo recomends that you do not do this. Volvo is owned by Ford.

jsiburt · Jul 13, 2003, 10:32 PM

Actually I was having the charging problem where the charger would stop charging unless I unplugged and plugged it in again. The point is that Apple said it was the surge strip, they were correct. Once I plugged it into the wall no more problems.

But now it no longer charges the way it did before, charge to 100% trickle done to 95% then charge to 100% again. Now it takes it a day to drop to 99% and then the next day it is at 98%. So I believe some damage may have occurred because the trickle is much much slower.

I did reset the PMU when I was trouble shooting the charging issue. Any thoughts?

geekwagon · Jul 14, 2003, 03:46 PM

Originally posted by tooki:
Geekwagon, what you're doing is completely pointless.

Each battery has a microcontroller inside it that talks to the power manager inside the PowerBook. It knows that it's just at 94%, and won't start a whole start-to-finish charge cycle. It'll just trickle it up to 100%.

The power manager combined with the "smart" batteries mean that, as far as you are concerned, it works like a gas tank in a car: when you go to fill up, the pump pumps till it's full. But unlike with a gas pump, there is no way to wiggle the nozzle to get a couple more drops in.

tooki

I think you are missunderstanding my point. There are times when I may need that last 5-10 minutes of charge that being at 100% provides me over being at 95%. My Powerbook has been running off AC for a while, therefore it has gradually trickled itself down to 95%. So, I just tell it to start charging again (to get it to 100%) by unplugging it for a few minutes so the powermanager will decide to start charging.

Pretty simple.. I am not trying to break the laws of physics or anything by making the battery hold more than it is rated as. I am just trying to make sure that in rare circumstances I have 100% of the capacity of my battery available to me.

In your analogy, it is similar to a gas station refusing to fill your car because you haven't used enough gas yet (your tank is still too full.) So, you have to work around it by going around the block a few times to use up some fuel so the station will fill you up before you head off across the desert.

geekwagon · Jul 14, 2003, 03:51 PM

Originally posted by jsiburt:
[B]
But now it no longer charges the way it did before, charge to 100% trickle done to 95% then charge to 100% again. Now it takes it a day to drop to 99% and then the next day it is at 98%. So I believe some damage may have occurred because the trickle is much much slower.
B]

My 17" trickle drains at about 1% per day most of the time.. It doesn't really sound like a problem to me.

poocat · Jul 16, 2003, 11:28 PM

my battery has started to not recharge.

it trickles down, about one percent every two or three days, (pismo5, battery only one year old) but now it just stays down. does anyone know how to reset it? it's at 89% now... i'd like to figure this out before it gets lower. can i drain the battery and recharge? is that a good idea? what do you suggest?

thanks.

poocat.

coolmacdude · Jul 17, 2003, 01:02 AM

Apple provides an excellent explanation here.