Can you leave the laptop plugged in?

I mainly use my laptop at 2-3 different desks, and it’s plugged in 99% of time. Will this damage the battery or is the motherboard clever enough to circumvent the battery when it’s fully charged and power the laptop directly?

Are there any recommendations for preserving battery health when you always have the laptop plugged in? For example is there any point in limiting the max battery level in the BIOS?

Hardware: AMD Ryzen 5 laptop

Software: OpenSUSE with KDE Plasma and power-profiles-daemon installed (tlp removed)

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Unchanged, the behavior is that the laptop would charge to 100% and stay there if left plugged in. Sitting for long periods at 100% is hard on the battery and will potentially cause the battery to degrade more rapidly over time.

There is an option in the BIOS to limit the maximum charge level. This will cause the battery to stop charging when it reaches the set threshold. Setting a max battery charge threshold of 80% or lower would be a “healthier” place for the battery to sit for extended periods. And it shouldn’t affect operation if you leave it plugged in the majority of the time. Even when you do have to run “unplugged” it will simply reduce the battery life by whatever precent below 100 you set.

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If it stops charging once the threshold is reached, what’s the point of choosing a lower maximum like 80%?

It has to do with the chemistry of Li-ion cells (that I dont fully understand either), but having them sit at maximum voltage/% charge is bad for their longevity.

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As Nich_Trimble said, it has to do with the chemistry of the cells. When the cells are at a high state of charge, the internal chemistry causes the cells to degrade more quickly. At lower charge levels, the internal chemistry is more stable and the cells won’t degrade quite as quickly. 80% is a good compromise of reducing degradation over time, while still providing reasonable battery run time when used unplugged.

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Also, to be clear, you can leave it plugged in without changing anything. It will stop charging when full and it will be fine. The battery won’t fail immediately or anything. It will just lose capacity over time a bit more quickly than if it was sitting at a lower state of charge. Framework provides the option to limit the maximum charge level in the BIOS if you so choose, but it’s not required.

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I think the very best practice is to set a limit (as described in this thread) but to also set a threshold, such that charging does not BEGIN until the battery has been discharged to a certain level. (For example, one could set a limit of 80% and a threshold of 40%.) As I understand it, we can set a limit in BIOS, but there’s no way to set a threshold at this point.