How do you charge your laptop battery?

I have always known, that the Li-ion battery should not be kept 100% charged. I got used to unplugging the charger at 100% and plug in back at about 20%. My new laptop manual, however, states as below:

To optimize battery life and avoid a sudden power loss, read the tips below:

  • Suspend system operation if the system will be idle for a while or shorten the suspend timer’s time period.
  • Turn off the system if you won’t be using it for a period of time.
  • Disable unnecessary settings or remove idle peripherals.
  • Connect an AC/DC adapter to the system whenever possible.

When fully charged, the hardware charging LED goes off, the acpi command returns Battery 0: Full, 100%. For many reasons it would be comfortable to me not to disconnect the charger, but I’m afraid it may shorten the battery life.

What do you think?

I think they say that because when not plugged in there can be power saving features enabled and lower system performance. Any laptop should be directly using the DC coming in from the cord brick and not taxing the battery, this is also why it pulls some 19V, 12 for the system and the rest for battery charging. They also will disable charging once the battery hits a charged threshold so no worries of over charging/wear.

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You won’t run into any problems leaving it plugged in. According to this website:’s%20no%20danger%20of%20overcharging,a%20battery%20will%20damage%20it.

A battery cannot be overcharged. There’s no danger of overcharging a battery if you leave it plugged in all the time. As soon as it hits 100 percent it will cease charging and won’t start again until the voltage falls below a certain level.

If anything, leaving your laptop plugged in will actually HELP increase your battery’s lifespan, because batteries only have a finite amount of times they can be discharged/charged. The more you leave it plugged in, the less it discharges/recharges, and as a result the battery lasts longer.

Your bigger danger is if you completely discharge the battery, which is something I’ll accidentally do every now and then. :neutral_face:

Yes good point

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Load cycles are more important than charge cycles and leaving the battery permanently plugged in can result in higher temperatures, which is detrimental to battery life.

The firmware won’t let you do that, it will always keep a reserve charge and turn off the machine before that runs out.

To fully conserve the battery remove it :slight_smile:

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Even more: on kernel version >= 4.6 the discrete graphics does not start properly without the charger, which results in systemd crashes. It doesn’t happen on the LTS kernel.

That’s what I wanted to know.

Damned MSI built it into the case! No way to remove without a screwdriver. :rofl:

Even Lenovo have started doing that with their ThinkPads now. I blame Apple :angry:


Same with my Acer Aspire 15 and HP x360
I guess companies want you to believe a battery replacement should actually be a Laptop replacement LOL

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Sorry for OT, but I must say this:

My 5 years old Chromebook since Monday keeps showing the message:

This is the last automatic software and security update that this device receives (Chromebook). To receive updates in the future, switch to a newer model.

Looks like you’ll need to switch your Chromebook over to Linux!

Dunno how well it will work with 32-bit ARM, but the URL above mentions it so it’s always worth a shot!

Hi Team,
laptop techlastf7 : i don’t have suspect some battery problem. It is in charge to 100% and i keep it plugin on charge after. No problem if i unplugged, a good life battery, not if is use zoom with video conf.
Keep plugin for me :wink:

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If it stops working one day, to browse the web in bed, the Chromium OS should be more than enough. :slight_smile:

Planned obsoletness at it s best.


Funny how they don’t mention that in their adverts…


Pretty sure they do in the overview buts it’s worded subversively

These updates depend on many device specific non-Google hardware and software providers that work with Google to provide the highest level of security and stability support. For this reason, older Chrome devices cannot receive updates indefinitely to enable new OS and browser features.



Not sure how universal this trick is but I’ve just discovered that Linux exposes charge thresholds for my ThinkPad in /sys/class/power_supply/BAT0/charge-start-threshold and /sys/class/power_supply/BAT0/charge-stop-threshold.

Most guides on the interweb advise the use of tlp to set charge thresholds for ThinkPads, which used to need the custom tp-smapi kernel module[0] but they are no longer needed because the thresholds can be set with a simple udev rule :slight_smile:

Here’s mine (/etc/udev/rules.d/00-chargethresholds.rules):

 SUBSYSTEM=="power_supply", ATTR{charge_start_threshold}="45", ATTR{charge_stop_threshold}="55"

^ With that rule the laptop stops accepting charge at anywhere between 45% & 55% and will hold the battery at that level, thus conserving battery life by preventing full charge or load cycles.

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Tlp thresholds work on ThinkPads only, AFAIK.

I know nothing about udev rules, but this may be worth of try. However, it’s possible that my MSI has some built-in control. When plugged in, it charges up to 100%, and after some times starts discharging down to 89% - and start charging again.

Another interesting fact: without TLP installed, it slows down CPU clock speed when unplugged. No single mention in the users’ guide, of course.

Yes, that’s right but if your battery exposes charge thresholds via sysfs then you should be able to set them without tlp.

Weirdly I don’t seem to need an udev rule at all — the thresholds “stick” once they’re set and maintain the same value even through reboots and shutdowns. I booted into Debian and the thresholds were still set and honoured there.

So all that’s needed is

echo 45 > /sys/class/power_supply/BAT0/charge_start_threshold
echo 55 > /sys/class/power_supply/BAT0/charge_stop_threshold

No BAT0 folder on my machine:

$ ls /sys/class/power_supply

$ ls /sys/class/power_supply/BAT1
alarm capacity_level charge_full_design current_now device manufacturer power serial_number subsystem type voltage_min_design
capacity charge_full charge_now cycle_count hwmon6 model_name present status technology uevent voltage_now

Should I use BAT1 or leave as is?