I'm very conscious about the life of battery.

Some people say that don't keep plugged-in laptop all over the time and remove battery charging at 70% and again charge at 40% so your battery cells don't charge or discharge at their full position, and battery cells will keep at their optimal voltage rate.


Some of says keep your battery plugged-in all the time so that your battery will not be used by laptop and battery's life cycles will not drain and important this is laptop will stop battery charging automatically when it reached to 100%

Which is true?


2 Answers 2


The best report on this subject


The lowest aging rate is known to be 0'C 66% SoC which is the approx. SoC charge level used by OEM's to ship/store LiPo batteries.

Depth of discharge %DoD, greatly affects total lifetime Ah capacity.

             NMC     LiPO4
 100% DoD   ~300    ~600
 80% DoD    ~400    ~900
 60% DoD    ~600    ~1,500
 40% DoD    ~1,000  ~3,000
 20% DoD    ~2,000  ~9,000
 10% DoD    ~6,000  ~15,000

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Control depends on laptop OEM and bios + drivers. Lenovo has the best user options for float charge level and slow charge option prior to going mobile to get max capacity. Choose Longest life settings for 70% to 80% float SoC rather than 100%.

"A laptop battery could be prolonged by lowering the charge voltage when connected to the AC grid. To make this feature user-friendly, a device should feature a “Long Life” mode that keeps the battery at 4.05V/cell and offers a SoC of about 80 percent. One hour before traveling, the user requests the “Full Capacity” mode to bring the charge to 4.20V/cell"

Also FYI http://batteryuniversity.com/learn/article/why_mobile_phone_batteries_do_not_last_as_long_as_an_ev_battery




  • 1
    \$\begingroup\$ i really appreciate your research and knowledge. thanks for these useful information and link. \$\endgroup\$ Jan 12, 2020 at 18:01
  • \$\begingroup\$ 100% is not the best since leakage demands recharge hourly /daily?? resulting in excess time spent above 3.9V which degrades battery even when not being used much. (<10%) \$\endgroup\$ Jan 12, 2020 at 18:06
  • \$\begingroup\$ Should I Leave My Laptop Plugged In All The Time? There’s no way to “overcharge” these batteries. When you get to 100% charge and leave your laptop plugged in, the charger will stop charging the battery. The laptop will just run directly off the power cable. After the battery discharges a bit, the charger will kick into gear again and top the battery off. There’s no risk of damaging the battery by charging it over its capacity. but keep battery temperature normal. \$\endgroup\$ Jan 13, 2020 at 4:59
  • \$\begingroup\$ But Should I Leave It Plugged In or Not? battery at 100% capacity will decrease its lifespan, but running through repeated discharge and recharge cycles will also decrease its lifespan. Basically, whatever you do, your battery will wear down and lose capacity That’s just how batteries workThe real question is what makes it die more slowly and follow that procedure that is keep plungedin all the time so your battery life cycles will not decrease and battery will work last long rather the you discharge or recharge the battery and reduce its life cycles and power capacity more quickly \$\endgroup\$ Jan 13, 2020 at 5:09
  • \$\begingroup\$ source : [howtogeek.com/124715/… \$\endgroup\$ Jan 13, 2020 at 5:09

You'll find yourself in a situation where both are true.

Point is: the aging processes in your Lithium battery are are dominated by usage (especially: decomposition of the electrolytic carriers, and forming of metal dendrites at high currents). Obviously, not using the battery will avoid these. Lithium Batteries have an excellent shelf life.

Leaving them in the laptop while always powering that, however will not guarantee the battery is never used. That depends on how the charging and powering electronics' firmware in your laptop has been designed.

While not being used, the main aging factor in batteries (of practically all kinds) is osmosis of chemicals through membranes that shouldn't let them through – and osmosis speed goes with the square of concentration difference, which goes linearly with charge. So, for prolonged storage, discharging to somewhere between 40 and 70% does seem a good thing.

But: What use is a stored battery? If you ask me, a battery is "old" when it doesn't have 70% of the original battery life. So, if you force yourself to keep below that charge, great, your life is as bad as that of someone with an "old" battery.

So, seriously, use your battery, and buy electronic devices where the main battery can be exchanged either trivially (Business laptops often have batteries that you can simply click in and out – usage hint: for someone who doesn't need a high-end gaming laptop, a used 3 year old business laptop plus a new battery is often better and cheaper than a new consumer laptop) or are known to be well-replaceable with good replacement batteries (phones, mainly).


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