Does battery life decreases when plugged in or overcharged?

Question

My laptop is always plugged in when it is switched off and i many times forget to remove the charger.

Answer 1

As long as the laptop is relatively new (in the last few years), it is not likely to make a lot of difference. This is especially true of the better makes such as Lenovo as they have smarter power monitors.

In theory, keeping your battery charged to around 80% is the best for it & some power tools try to do this (Lenovo and Dell for example).

If you really don't need the flexibility of being able to grab the laptop and move around, you could remove the battery but you would need to remember to put it back on every few months to keep some charge in it. In all honesty, it is as likely that your laptop will be defunct by the time the battery gets to an unusable point. I've had a couple of laptops where the battery did die but these were old before I even got them and I just used them as "desktops" for a few more years - they were fine for the kids.

Answer 2

As you can imagine your laptop battery will decrease overtime regardless of what you do with it (this includes taking it out and putting it in a corner). Newer lithium ion batteries and varies technologies included with your system reduce any ill affect from overcharging by providing a discharge capability once your battery when it hits its peak charge point.

Sadly this doesn't mean your battery is safe, it will still decrease over time just not as fast as older batteries. Most sources suggest for optimum performance you should charge/discharge your battery as you use it. I have followed this position and still have a laptop battery lasting 2 hours at full charge after 3 years.

Source
Source

Answer 3

1. Heat. Heat decrease durability of any materials, those of Your batteries included. And that heat is produced by charging to the max (or over).

2. Mechanical durability. Battery is one big bag of moving elements -> Electrons. And we call all that movement Current. It take its toll on the battery every recharging.

So Unless You have supper durable battery or some fancy circuitry that cut battery out when plugged in to other power source, its better to:

• Unplug Your battery when You do not need it.
• Avoid emptying or charging to the max (more heat from recharging is produced)

Ofc. current tech allows for 2-3y of good battery life. Taking care of Your batter can add 2y to that number.

Answer 4

Battery life is decreased by just about everything.

With Li-Ion, the three big killers are heat, running the battery totally flat, and overcharging. The built-in power controller generally covers the last two and does what it can about the first.

Some laptops have an option in their power settings that cause the battery to only be charged to about 80%, vs the 100% that would give you the max "unplugged" run time. This setting is to be desired for a laptop that is mainly used plugged in, since keeping a battery charged to 100% shortens its life.

When stored for long periods, though, it's important that the battery remain charged reasonably well -- above 50% at least. Don't store a battery when it's "flat".