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Author Topic: Is removing a laptop battery a good idea?  (Read 10658 times)

Offline Bill.D.Katt.

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Is removing a laptop battery a good idea?
« on: 23/11/2010 16:35:52 »
Is this a good idea? Will it increase battery life or laptop life?


 

Offline Bill.D.Katt.

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Is removing a laptop battery a good idea?
« Reply #1 on: 30/11/2010 21:04:17 »
Maybe I should clarify: I removed the battery, and am just running on the plug in when I work on the laptop.
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #2 on: 30/11/2010 23:47:27 »
I don't thik it will effect the life of either the battery, or the laptop. It will be a pain if there is a power failure while you are using it though. With the battery in, it will keep running.
 

Offline peppercorn

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Is removing a laptop battery a good idea?
« Reply #3 on: 01/12/2010 11:12:25 »
My (really quite old) laptop regularly pulses power to the battery when it is clearly already topped up.  This might be a good thing on a Lead-acid but I;m pretty sure it's not on a Li-Ion.  Note: the battery will only kep the laptop alive for about 10 mins when power is off!
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #4 on: 01/12/2010 18:01:23 »
My (really quite old) laptop regularly pulses power to the battery when it is clearly already topped up.  This might be a good thing on a Lead-acid but I;m pretty sure it's not on a Li-Ion.  Note: the battery will only kep the laptop alive for about 10 mins when power is off!

I think it may be time to toss the battery, if not the entire laptop  ;D
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #5 on: 01/12/2010 18:04:16 »
BTW, this may be slightly amusing when it happens to a laptop, but it will highly unamusing if when it happens to the batteries in your all electric car!!
 

Offline peppercorn

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Is removing a laptop battery a good idea?
« Reply #6 on: 01/12/2010 18:53:35 »
My (really quite old) laptop regularly pulses power to the battery when it is clearly already topped up.  This might be a good thing on a Lead-acid but I;m pretty sure it's not on a Li-Ion.  Note: the battery will only kep the laptop alive for about 10 mins when power is off!
I think it may be time to toss the battery, if not the entire laptop  ;D

Huh! And you call yeeself a Scot with that attitude! :D
While it still works I think I'll hold onto it, thanks!  It's not as if ever use it out of the house anyway.

I suppose a battery that lasted a proper amount of time might not keep giving the impression to the laptop that it needed topping up all the time.
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #7 on: 01/12/2010 21:44:17 »
While it still works I think I'll hold onto it, thanks! 

You could also sit on it and use it as a bum warmer. Looking at the weather reports, I think you might need it.
« Last Edit: 01/12/2010 21:53:22 by Geezer »
 

Offline peppercorn

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Is removing a laptop battery a good idea?
« Reply #8 on: 01/12/2010 22:55:21 »
While it still works I think I'll hold onto it, thanks! 

You could also sit on it and use it as a bum warmer. Looking at the weather reports, I think you might need it.

;D Is is still -10°F over there?
« Last Edit: 02/12/2010 11:08:52 by peppercorn »
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #9 on: 02/12/2010 04:36:54 »
Is is still -10 F over there?


It's back up to a more typical 32 ish. We did set a new record for November snowfall.
 

Offline maffsolo

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Is removing a laptop battery a good idea?
« Reply #10 on: 02/12/2010 05:54:27 »
Is this a good idea? Will it increase battery life or laptop life?

Keeping the battery and charger plugged in is placing the load on the charger and the battery simultaniously, providing the battery is near or at full charge. The battery acts also as an extra capacitive DC filter, using it with the charger. Sharing the current strain between each component extends there life.
I have kept batteries in my freezer for a few years and were still good.

Keeping a battery from totally discharging is best.
 I do not know if this is a cross the board statement, but I have seen batteries reverse polarity when there discharge is over maxed.
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #11 on: 02/12/2010 06:22:07 »
Is this a good idea? Will it increase battery life or laptop life?

Keeping the battery and charger plugged in is placing the load on the charger and the battery simultaniously, providing the battery is near or at full charge. The battery acts also as an extra capacitive DC filter, using it with the charger.


Maff, I think the charging algorithm in a PC is quite sophisticated. When the battery is fully charged, no more charge current will be supplied. The system probably checks the battery periodically to determine if the battery should be charged, but it won't charge it unless it's necessary.

Peppercorn's battery is obviously a goner, so his PC keeps trying to charge it up.
 

Offline peppercorn

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Is removing a laptop battery a good idea?
« Reply #12 on: 02/12/2010 11:19:26 »
Peppercorn's battery is obviously a goner, so his PC keeps trying to charge it up.

Yes - this is the likely explanation.  Maybe an charge override switch would useful when the batteries get a few years old - all these tens of thousands of short pulses can't be good.

I have quite a few batteries (for other laptops) that are all about 3-4 years old, but I don't know their usage history.  How can I test the health of each 3.7v cell to get a rough idea of which ones are worth using?  I believe the two easier tests are measuring internal resistance and some version of a short-cct test - any idea?
 

Offline CliffordK

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Is removing a laptop battery a good idea?
« Reply #13 on: 02/12/2010 14:20:03 »
I think the computers are getting better with their charging algorithms to avoid overcharging & overworking the battery.

However, if you have a NEW (fully charged) battery and sit it on the shelf for 5 years, in all likelihood, it will be better than the battery that has been used in the computer for the same 5 year period.

There are also random things that will torch a battery including the battery monitoring gizmos built into the battery packs.  So, if your battery is 90% good one day, and 100% bad the next, it is probably faulty circuitry, and not faulty cells.
 

Offline maffsolo

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Is removing a laptop battery a good idea?
« Reply #14 on: 02/12/2010 16:31:33 »
Is this a good idea? Will it increase battery life or laptop life?

Keeping the battery and charger plugged in is placing the load on the charger and the battery simultaniously, providing the battery is near or at full charge. The battery acts also as an extra capacitive DC filter, using it with the charger.


Maff, I think the charging algorithm in a PC is quite sophisticated. When the battery is fully charged, no more charge current will be supplied. The system probably checks the battery periodically to determine if the battery should be charged, but it won't charge it unless it's necessary.

Peppercorn's battery is obviously a goner, so his PC keeps trying to charge it up.

Battery monitoring is not done by a simple voltage theshold on a component, triggers activation of a charge mode any more? 
 

Offline peppercorn

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Is removing a laptop battery a good idea?
« Reply #15 on: 02/12/2010 16:53:54 »
Peppercorn's battery is obviously a goner, so his PC keeps trying to charge it up.

This would point to it measuring the cell's internal resistance to 'judge' whether charging is required.  All batteries I've opened have had a single temperature sensor, but this is for thermal protection only I believe - If a cell is shorting, etc.
« Last Edit: 02/12/2010 17:02:40 by peppercorn »
 

Offline Geezer

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Is removing a laptop battery a good idea?
« Reply #16 on: 02/12/2010 22:39:57 »
Peppercorn's battery is obviously a goner, so his PC keeps trying to charge it up.

This would point to it measuring the cell's internal resistance to 'judge' whether charging is required.  All batteries I've opened have had a single temperature sensor, but this is for thermal protection only I believe - If a cell is shorting, etc.

I've never messed around with lithium-ion batteries. Is that how you tell their charge state?
 


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Is removing a laptop battery a good idea?
« Reply #17 on: 03/12/2010 00:00:44 »

 

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