Weird laptop battery drain

Lestratcaster

This has happened a couple of times. Fire up laptop. Battery percentage is on 43% or less than 50% anyway. No issues, turn on audio interface and speakers etc. Then leave it to go open the door to let my clients in. Come back and in a few minutes the laptop has died. No power at all. How can it go from 43% to zero in the space of 5 minutes?

Have to turn on the charger then boot up again and it turns back on again. Windows 10, laptop is coming up to 4 years old.

bertie

is it running out of  juice or just powering down/stand-by ?

could be power settings ?,   you can configure individual things to be "stopped/shutdown/disabled" dependent on remaining  battery life

Lestratcaster

It just completely dies. When the client came in and I went to look at the screen it was off, and no lights were on. I pushed the power button and it wouldn't turn on. Only when I turned the charger on it powered on, the battery status said 0% (charging).

There might be something in the power settings I can change, when I'm in the room using it and its dropped below 20% it enters power saving mode but still runs fine. Only when I leave it for over 10 minutes does it shut off with more battery life for some reason.

bertie

Lestratcaster said:

It just completely dies. When the client came in and I went to look at the screen it was off, and no lights were on. I pushed the power button and it wouldn't turn on. Only when I turned the charger on it powered on, the battery status said 0% (charging).

There might be something in the power settings I can change, when I'm in the room using it and its dropped below 20% it enters power saving mode but still runs fine. Only when I leave it for over 10 minutes does it shut off with more battery life for some reason.

if the battery shows 0% at start up,  then its unlikely to be the settings TBH, Id say the battery was on the way out -    what happens if you let the battery charge right up ?   (TBH I never dont use the charger at home  - never use battery only)

BillDL

As far as I understand it you can run a cycle of charging and fully discharging while recalibrating the system so that the computer knows when the battery is at the depletion level where it needs to power it off.  Have you checked the manual to see if it mentions such a thing?

Lestratcaster

If I let it charge it goes to 99% or full then I switch off the charger.

Lestratcaster

BillDL said:

As far as I understand it you can run a cycle of charging and fully discharging while recalibrating the system so that the computer knows when the battery is at the depletion level where it needs to power it off.  Have you checked the manual to see if it mentions such a thing?

I don't think it came with manual, if it did I can't find it so I'll have to hunt for one online somewhere.

Danny1969

The laptop gets the battery level from the BMS chip in the battery. This is a voltage level so only a rough guide to how long the battery might last ... how long it actually last is dependent on the condition of the actual materials in the battery. Basically over time the battery will self discharge through it's self internally. 
The BMS chip won't allow the cells to drop below 2.8V generally .. if it gets close it will turn the battery off regardless of what the laptop says. 

Change the battery but be careful of fakes. 

bertie

Danny1969 said:

 

Change the battery but be VERY careful of fakes. 

FTFY

Lestratcaster

Will hunt around for a new battery. Could I not just use it plugged in if it does drain quite quick? I.e take it out and just use the charger as a mains adaptor.

Danny1969

Lestratcaster said:

Will hunt around for a new battery. Could I not just use it plugged in if it does drain quite quick? I.e take it out and just use the charger as a mains adaptor.

Depends on the model ... if it's an external clip in battery then yes. If it's a more modern design with internal pouch battery then yes or no.  Some generic and Apple laptops run off the battery, others are quite happy running off a charger alone. 

m_c

I've got a couple fairly new laptops that have an issue with the indicated battery life.
It seems that when the laptop hasn't been used for a few weeks, the battery drains, but whatever monitors the battery charge level doesn't update, so when you do turn them on, they show the battery level from when they were last used, but will turn off due to low battery. Once plugged in, the battery level shows as expected.

They are fairly cheap laptops, so I suspect whatever does the battery energy monitoring doesn't use the battery voltage, and isn't active when the laptop is switched off.

Lestratcaster

Danny1969 said:

Lestratcaster said:

Will hunt around for a new battery. Could I not just use it plugged in if it does drain quite quick? I.e take it out and just use the charger as a mains adaptor.

Depends on the model ... if it's an external clip in battery then yes. If it's a more modern design with internal pouch battery then yes or no.  Some generic and Apple laptops run off the battery, others are quite happy running off a charger alone. 

It's the HP Pavilion CW1507 one and yes its a clip in battery, I had to remove it to add more RAM last year.

Lestratcaster

m_c said:

I've got a couple fairly new laptops that have an issue with the indicated battery life.
It seems that when the laptop hasn't been used for a few weeks, the battery drains, but whatever monitors the battery charge level doesn't update, so when you do turn them on, they show the battery level from when they were last used, but will turn off due to low battery. Once plugged in, the battery level shows as expected.

They are fairly cheap laptops, so I suspect whatever does the battery energy monitoring doesn't use the battery voltage, and isn't active when the laptop is switched off.

Actually I didn't use it for a whole day the day before so that might have caused it to drop, but it doesn't happen all the time. Sometimes when its on like 30% or lower I'll stick it on charge for about half an hour just to bring it back up to 50% or so when I use it when next turning it on.

Danny1969

All batteries fail over time unfortunately but another one only be £45 ish

HP use a coms pin on their chargers ... it's that little pin dead in the centre of the charger end. Often that gets bent and then all kinds of problems will start but I think if your battery charges then it's just a case of it's worn out and needs replacing. 

Lestratcaster

Yeah so something like this?

HP Pavilion 15-CW1507SA - Replacement Laptop Battery 3 Cell (thelaptoppowersupplyshop.co.uk)

Do I need to be paying any attention to the mAh value? Or are they essentially all the same?

Danny1969

Oh you have a Pav 15 ... the battery pack  in those often start to swell when failing 

There's an HP part number on the battery ... be something like 920070-855  Buy the same one 

Lestratcaster

Yeah its a 15. Funnily enough I used it earlier, and it dropped to 20% and entered power saving mode (usually when I turn the charger on). It didn't switch off though.

I'll have a look inside to get the part number.

Lestratcaster

Actually I took a photo of it last time I opened it to install extra RAM. There seems to be a few numbers on the battery:

Is it the HT03XL number or the L11119-855 number?

Kittyfrisk

Lestratcaster said:

Actually I took a photo of it last time I opened it to install extra RAM. There seems to be a few numbers on the battery:

Is it the HT03XL number or the L11119-855 number?

The white label, top right says "`Replace with HP spare L11119-855"

Lestratcaster

Yeah I typed it into google but there didn't seem to come with very many results, maybe I missed one of 1's or put too many.