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Laptop battery recalibration?

#1

DarkAudit

DarkAudit

I've got an HP Pavilion laptop that is just over a year old. Recently it's developed a habit of snapping off without warning when running on battery and the battery reaches a 50% charge. I've tried the recalibration methods suggested by HP support, and the battery seems to pass it's tests, but it's still shutting down at 50% and won't come back on until I've plugged in AC power.

Suggestions?


#2

PatrThom

PatrThom

If it's a lithium battery, you can kind of even them out by running them all the way down as slowly as you can stand and then filling them back up again a few times. In fact, you're supposed to do this once every month or two to keep them from getting stale. Not until they're completely and utterly dead and you lose your time and date, just down to the point where the device tells you, "Ok, I'm going to sleep now."
But if your symptoms are because one of the cells is bad, the only real way is to swap out the battery.

--Patrick


#3

strawman

strawman

This usually indicates that one of the cells in the pack is bad, and replacing the whole pack is usually the only solution. You might be able to buy some time following some of the paths suggested, like going through several discharge/charge cycles, but those typically only help when a pack is unbalanced, not when a cell is dead (though the dead cell is most often cause by an unbalanced pack, so generally you may want to adopt a discharge/charge pattern once a month for your next pack)

If it were apple that would be different, apple really has one of the best battery maintenance and charging designs in the consumer market. It's really the only reason they've been able to get away with non consumer replaceable packs for years now without a mutiny, and why other mobile devices that have gone down that path have switched back.


#4

Dei

Dei

I had an HP laptop that this happened to about 10 years ago and even replacing the battery didn't fix it. I never did figure out the problem, even after trying every possible solution on the internet. :/


#5

DarkAudit

DarkAudit

The hardware tests all came back OK, yet when I did the extensive hard drive test that is supposed to drain the battery, it quit after less than 10 minutes. When I plugged the AC back in and rebooted, it reported a 92% charge. Something is very not right here.


#6

DarkAudit

DarkAudit

stienman said:
This usually indicates that one of the cells in the pack is bad, and replacing the whole pack is usually the only solution. You might be able to buy some time following some of the paths suggested, like going through several discharge/charge cycles, but those typically only help when a pack is unbalanced, not when a cell is dead (though the dead cell is most often cause by an unbalanced pack, so generally you may want to adopt a discharge/charge pattern once a month for your next pack)

If it were apple that would be different, apple really has one of the best battery maintenance and charging designs in the consumer market. It's really the only reason they've been able to get away with non consumer replaceable packs for years now without a mutiny, and why other mobile devices that have gone down that path have switched back.
Click to expand...
I don't have a dead cell, but one of them is showing a marked difference in voltage compared to the other three.
Cell 1: 4116mV
Cell 2: 3990mV
Cell 3: 4101mV
Cell 4: 4120mV


#7

strawman

strawman

DarkAudit said:
I don't have a dead cell, but one of them is showing a marked difference in voltage compared to the other three.
Cell 1: 4116mV
Cell 2: 3990mV
Cell 3: 4101mV
Cell 4: 4120mV
Click to expand...
Charge it up to 100%, check the cell voltages, then run it for 5 minutes, check the cell voltages again, and keep doing that until it dies. You'll get a nice chart showing which battery is dropping faster than the rest. Once that cell gets to a certain voltage, the pack electronics will shut the whole thing down to avoid discharging the cell further.

Chances are good one cell will have a trend that falls much more quickly than the rest.[DOUBLEPOST=1493041996,1493041941][/DOUBLEPOST]You may be able to find a place that will replace just one cell, but my experience is that it's cheaper to replace the whole pack anyway.


#8

PatrThom

PatrThom

And you'll probably find that your computer shuts off when that one cell drops < 3100mV.
Interestingly, it appears you get the best lifespan out of a Li-ion battery if you keep it between 20-80% and avoid heavy use, so use those full empty/fill retrain sessions sparingly, and possibly not every couple of months as I suggested earlier, but rather as needed.

--Patrick


#9

DarkAudit

DarkAudit

And now it's not charging at all unless the computer is on. And even then the percentage is stuck. Won't turn on unless it's on AC, and immediately shuts off if I pull the adapter.

And yet it tests "ok"?


#10

DarkAudit

DarkAudit

Updated the UEFI Diagnostic software, and its test stopped saying the battery was "too full" (>90% charge) to continue. Said to disconnect AC to run down the battery, and if it wouldn't run on batter like that, replace it.

Well, that happened. Will need to hit up Best Buy later this morning for a new one.

Other symptoms still happening. Will not attempt to charge unless powered on, but will not actually charge when it is. Stays stuck at whatever percentage is originally reported. AC pack gets warm when battery is attached. If AC is removed, will either immediately shut off or will not power on at all.


#11

DarkAudit

DarkAudit

New battery acquired and installed. Began charging right away, which the other one wasn't doing. On battery power now and all four cells are about equal. So the "out of balance" thing seems to be the cause of the other battery's failure.


#12

strawman

strawman

Glad to hear it!It's much worse (ie, more expensive to find and fix) when a new battery doesn't fix the problem.


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