Leaving a laptop plugged in ruins the battery when fully charged?
- Thread starter korakebu
- Start date
I don't think it is anymore to be honest, it probably is true for older systems (maybe) with older power delivery/management systems. I don't think it is the case with modern laptops which oftentimes need to be plugged in to get the best performance out of them.
I don't have evidence of this, and haven't attempted to google to confirm/deny - so happy for anyone else to come and demonstrate why this is incorrect but its how I understand things today.
I don't have evidence of this, and haven't attempted to google to confirm/deny - so happy for anyone else to come and demonstrate why this is incorrect but its how I understand things today.
ubuysa
The BSOD Doctor
No, it's not true. A genuine myth. The charging systems in modern laptops will not overcharge or damage the battery at all. What will shorten the life of the battery is heat, so it's worthwhile getting a fan assisted cooling pad to keep not just the laptop cool but the battery as well.
Despite the name, a laptop should never be used on your lap or in bed, or on any soft surface (a cushion for example). Doing any of these blocks up the intake vents which are usually on the bottom, this leads to overheating inside the laptop. That's bad for the laptop and bad for the battery as well.
Bradden
Bronze Level Poster
The manual with my vortex ix says this:
Battery life may be shortened through improper maintenance. To optimize the life
and improve its performance, fully discharge and recharge the battery at least
once every 30 days. We recommend that you do not remove the battery yourself.
It then goes on to explain how to achieve this:
How do I completely discharge the battery?
Use the computer with battery power until it shuts down due to a low battery. Don’t
turn off the computer even if a message indicates the battery is critically low, just let
the computer use up all of the battery power and shut down on its own.
1. Save and close all files and applications.
2. Create a power plan for discharging the battery and set all the options to Never.
3. Click Change plan settings (after creating it) and click Change plan settings >
Change advanced power settings.
• Low battery level = 0%
• Critical battery level = 1%
• Low battery action = Do Nothing
• Reserve Battery Level = 0%
I thought modern batteries were potentially damaged if completely discharged and there is little benefit to doing this.. am I wrong?
I've never completely discharged. I use the flexicharge option in bios where you can set the max and min charge levels.. I understand that charging repeatedly over 80% can shorten battery life.
FlexiCharger Enable (Advanced Menu > Advanced Chipset Control)
The sub-menu here allows you to enable/disable the FlexiCharger. The FlexiCharger
may be set to automatically start charging your battery when the battery reaches
a certain capacity level (e.g. you could start the battery charge level at 40%).
You can then set the level to stop charging (e.g. 100%), and of course this stop
charge level must be higher then the start charge level.
www.csmonitor.com
Just interested in your thoughts on this.
Battery life may be shortened through improper maintenance. To optimize the life
and improve its performance, fully discharge and recharge the battery at least
once every 30 days. We recommend that you do not remove the battery yourself.
It then goes on to explain how to achieve this:
How do I completely discharge the battery?
Use the computer with battery power until it shuts down due to a low battery. Don’t
turn off the computer even if a message indicates the battery is critically low, just let
the computer use up all of the battery power and shut down on its own.
1. Save and close all files and applications.
2. Create a power plan for discharging the battery and set all the options to Never.
3. Click Change plan settings (after creating it) and click Change plan settings >
Change advanced power settings.
• Low battery level = 0%
• Critical battery level = 1%
• Low battery action = Do Nothing
• Reserve Battery Level = 0%
I thought modern batteries were potentially damaged if completely discharged and there is little benefit to doing this.. am I wrong?
I've never completely discharged. I use the flexicharge option in bios where you can set the max and min charge levels.. I understand that charging repeatedly over 80% can shorten battery life.
FlexiCharger Enable (Advanced Menu > Advanced Chipset Control)
The sub-menu here allows you to enable/disable the FlexiCharger. The FlexiCharger
may be set to automatically start charging your battery when the battery reaches
a certain capacity level (e.g. you could start the battery charge level at 40%).
You can then set the level to stop charging (e.g. 100%), and of course this stop
charge level must be higher then the start charge level.
40-80 rule: New tip for extending battery life
Extend the life of a lithium cell by not topping it off. The 40-80 rule can extend the life of your battery, but be careful to keep it out of the heat.
www.csmonitor.com
Just interested in your thoughts on this.
RichardDavies99
Bronze Level Poster
I've had something like this on my current laptop, which I was mostly running off the mains then the battery wouldn't hold a charge.
Since I bought a replacement battery I've made sure I've disconnected the mains from time to time to use the battery.
Since I bought a replacement battery I've made sure I've disconnected the mains from time to time to use the battery.
ubuysa
The BSOD Doctor
That's for a NiCad battery that has a 'memory', Li-Ion batteries do not suffer from this problem and don't need discharging every few days. See this: https://batteryuniversity.com/learn/article/do_and_dont_battery_table
ubuysa
The BSOD Doctor
It's clear from lab tests that there is a lot of truth in this (see https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries), although I've seen it described as 'never discharge below 20% and never charge more than 80%'.Just interested in your thoughts on this.40-80 rule: New tip for extending battery life
Extend the life of a lithium cell by not topping it off. The 40-80 rule can extend the life of your battery, but be careful to keep it out of the heat.
It's my belief however that the biggest gains with this approach are to be found with the bigger (and more expensive) Li-Ion batteries such as those found in cars. Although laptops, tablets, and mobile phones will undoubtedly benefit from this regime I think the gains are likely to be small compared to the effort involved in managing the regime. But if you're prepared to put the effort in then there are some gains in life to be had. Bear in mind of course that getting a Li-Ion battery hot is likely to undo all of the gains made by this kind of charging regime!
I understand that the chargers for Li-Ion battery powered devices, and especially expensive ones such as you find for cars, never charge the battery to its absolute maximum capacity in any case. The charge level at which the charger turns off is a balance between extending the usable life of the battery and giving the user as long as possible running on battery power. In a laptop I think they probably do charge them as high as possible to get the maximum battery life - at least until the warranty expires.
It may be then that there are gains in lifespan to be had by manually ensuring the battery is always charged between 20% and 80%, but bear in mind that the Windows % charge indicator is likely to be too inaccurate to be used for managing this.My personal view then is that it's not worth the effort on a laptop (or a phone for that matter) but it's not a myth.
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FerrariVie
Super Star
Can anyone share how the flexicharge on the BIOS work? I saw that option, but couldn't understand as it has both minimum and maximum values. I do understand what the maximum value is for, but what would be the minimum charge?
What I really wanted to do was to never charge my battery over 80 or 90%, but not sure on how to achieve this. I don't want the laptop to discharge the battery frequently by its own, as I understand that this will only make the battery cycle count go higher and decrease the full capacity by a bit each time.
What I really wanted to do was to never charge my battery over 80 or 90%, but not sure on how to achieve this. I don't want the laptop to discharge the battery frequently by its own, as I understand that this will only make the battery cycle count go higher and decrease the full capacity by a bit each time.
Bradden
Bronze Level Poster
I thought this was the case... not sure why it's in the manual.. even has pictures of how to change settings stop the laptop powering down.
Bradden
Bronze Level Poster
I've set flexicharge to 40%min 80%max.. Basically, when the battery drops below 40 it charges up to 80. You could use any values you like really.
ubuysa
The BSOD Doctor
I've not heard of 'flexicharge' before, it does rather sound like a way to manage the 20% (or 40%) to 80% charge limits?
ubuysa
The BSOD Doctor
I've learned something new today!
Bhuna50
Author Level
This is why cars do not utilise the entire battery and although a battery may say its 75kw on a car, it may only use about 60 to 65 of that as the management system built in allows for a car to never fully charge or fully diminish its battery - ie it will probably only ever get to about 5% or 10% charge remaining through to 90 / 95% "fully charged" - as a driver though you will only ever be told its 0 to 100% - and also the reason why when you rapid charge the car it will only ever rapid charge to 80% and then start to slow right down as it nears the 100% so called charge.
This will help prolong battery life in an EV car and on a smaller scale a laptop battery
(I've done some reading into this as switching to a Full EV early next year - just waiting for them to build it LOL).
FerrariVie
Super Star
Sorry, I still don't get the minimum value. If the laptop is plugged in, then how is it ever going to reach 40%? Or if it's only on battery, how will it charge itself again after reaching 40%?
Bradden
Bronze Level Poster
A quick search shows that the out of date manual advice has been covered before it seems.
www.pcspecialist.co.uk
Any possible way to turn off battery charging.
So my question is there a way to turn off battery charging on Defiance Series 17.3 RTX laptop. Since it is a ultra book the battery is not removable. Is there some software or bios settings that I can use. I keep my laptop connected to outlet all time and would only want to use the battery if...
The battery went on my ASUS laptop and I used to always have it plugged in. Still haven't sorted the battery out so have to have it plugged in all the time, though that's no different than before, probably why I haven't sorted it.
It is a ASUS GL752VW, battery is 4Cells 3200 mAh 48 Whrs, whatever that is
It is a ASUS GL752VW, battery is 4Cells 3200 mAh 48 Whrs, whatever that is
FerrariVie
Super Star
Interesting... So what will happen if I put 80% minimum and maximum? It will stay at 80% all the time? That's what I want.
SpyderTracks
We love you Ukraine
Just posting my opinions on this, my laptop is a 2014 model.
When I first got it, I left it powered on at the wall all the time, even when it was switched off. First battery didn’t last long, I replaced it in 2016.
This second one, I leave the battery connected, but turn off the mains whenever I switch it off. Battery is still good with 16% wear according to HWMonitor.
I haven’t prevented full charge or minimum charge at all.
Obviously this is an older battery without “smart” regulation.
When I first got it, I left it powered on at the wall all the time, even when it was switched off. First battery didn’t last long, I replaced it in 2016.
This second one, I leave the battery connected, but turn off the mains whenever I switch it off. Battery is still good with 16% wear according to HWMonitor.
I haven’t prevented full charge or minimum charge at all.
Obviously this is an older battery without “smart” regulation.