How to maximise battery longevity

[Humberto]

By longevity I mean the number of times one can recharge the battery before it starts losing significant capacity.

How does one maximise the longevity of a rechargeable lithium battery, like the one in a laptop?

The information on the internet is contradictory.

My current thinking is to let the battery charge hover around 50 %, i.e., not to let it discharge completely, and not to recharge if fully, except, once in a while, an almost complete discharge, followed by a complete recharge, is healthy.

What do you think?

 

[chrisc]

The advice about draining the batteries applies to the olden days of Ni-Cd batteries, which had a strange memory effect, which prevented them from eventually being recharged fully. No Ni-Cd batteries in laptops, tablets or smartphones these days.

 

[saor]

I wonder something similar about my laptop battery: It's always plugged in via mains power. Is it best for the battery to stay in and always be 100% charged, or better to leave it out and it remains inactive for very long periods of time?

 

[Humberto]

My Lenovo Z570 has two battery modes when it is plugged in:

1. Optimise battery runtime: the battery is charged to 100 % and left there.
2. Best battery health: the battery charge is constantly 50 %.

 

[Rudimental]

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

 

[sajunky]

[*]Best battery health: the battery charge is constantly 50 %

^ This, if you focus on longetivity. Information is contradictory, as there is conflicting interest: battery longetivity vs battery performance. It is up to you do decide what is more important. Running it completely flat is more stressful than full recharge. By example if you use 50% method, then take it on the road and run out of battery, it is not good for your productivity nor battery life. Always full recharge before leaving your place.

Your comment on occasional full discarge cycle is correct. It has to be done occasionally not because of memory effect (like in Ni-CD chemistry), but because it will reset system counters. Use it when you notice degradated performance.

 

[Rickster]

Only charge when it says "battery is low please switch to ac adapter" and if you are always near a plug, when the battery is finished charging take out the battery and use direct AC power.

 

[Pooky]

My mom's laptop has some battery app by Lenovo, and if you set it on maximise battery lifespan, it won't charge above 60%.

 

[Terencek]

There a couple of potential problems with this, as I have discovered over years of working only with laptops in offices or on the move:
1) Taking the battery out when it's charged leaves you vulnerable to power outages, when you will lose everything. Keeping the battery in gives you an inbuilt "UPS" function, where the laptop switches to internal power the instant mains goes down.
2) Not all laptops like to have their battery removed. I killed a ThinkPad's BIOS battery by constantly removing the main battery, because its circuitry set the BIOS battery to charge from the main battery by default, so that removing the main battery put extra strain on the BIOS battery.

Of course your mileage may vary.... And what has been said above is true, that constantly topping-up a lithium battery is not as harmful as the process was to old NiCad or NiMH batteries.

 

[sajunky]

2) Not all laptops like to have their battery removed. I killed a ThinkPad's BIOS battery by constantly removing the main battery, because its circuitry set the BIOS battery to charge from the main battery by default, so that removing the main battery put extra strain on the BIOS battery.

Agree 100%, but not to explanation. Some laptops have secondary small backup NiMH battery (not only for CMOS).