Help Unplug phone as soon add charged

[jonny772]

I was talking with a woman at work that has an s4 and she was told to immediately unplug the phone or else this will shorten battery life. Any truth to this?

 

[Mdraej99]

I know that was true for older batteries.. but I think it stops charging now when it's fully charged. But I still take it off when it's done. I am sacred to take any chances.. lol

 

[Scootmien]

For older batteries this was indeed true.

For newer batteries it is no longer a requirement. The chargers and batteries on the new crop of phones will shut off and go into a trickle charge state (if needed) when they reach full capacity.

The only things you need to avoid doing too frequently are discharging the battery completely and letting it get too hot as these will both cause the charge capacity to deteriorate slightly over time.

 

[jonny772]

I thought as much, I think its just a case of old habits die hard. She swears that shes losing battery life from having done that I just think as batteries get older they dont work as well.

 

[GAWoods]

I was told the same by Samsung support when I contacted them about my poor battery life. I told them that I usually plug mine up when I go to bed and unplug in the morning when I awake. I informed them how inconvenient it would be to awake after a couple of hours just to unplug the phone. They replied sorry for any inconvenience. Not much help.

 

[Scootmien]

I thought as much, I think its just a case of old habits die hard. She swears that shes losing battery life from having done that I just think as batteries get older they dont work as well.

I bet you that as the woman has it instilled in her that you need to unplug the phone as soon as it gets to 100%, she is perceiving a shorter battery life if and when the phone isn't unplugged immediately upon 100%. I reckon that the degradation in battery life is far, far less than she perceives. It's the age old 'truth vs perception' argument that basically says that in subjective situations, your mind will perceive the truth to be whatever fits in with your world view. In her world view, the battery is lasting less and less time due to the fact that it stays on the charger after 100%. Only accurate measurements will turn this from subjective to objective truth.

It's human nature though, so i'm not having a dig at her.

 

[iTzKPanda]

This whole "when to plug-in/plug-out" nonsense usually does not apply most all modern smartphones with Li-Ion batteries.

Here's a quote that's pretty accurate:

There are a lot of misconceptions about charging cell phones, largely stemming imo from the older nickel-based batteries. The simplest way to put the matter is, with lithium ion, it's best to charge whenever possible. The higher the percentage, the better. Now, there is a bit more to that... Lithium ion batteries do not have memory issues like the older types do - if you charge it at 90%, or 20%, or even 01%, it does not affect the 'virtual' longevity of the battery. In addition, the lifespan of a lithium ion battery isn't significantly affected by what percentage you charge it at - they are rated for a certain amount of charge/discharge cycles (commonly 300-500, although this does vary), and charging from 90% to 100% is the same as charging from 00% to 10%. However, a full charge/discharge cycle does put more stress on the battery - you might have a small gain of lifespan if you charge with a smaller discharge depth. So you should be fine to let it drain, but if you're an OCD optimizer like I am, you're going to want to charge when you get the chance.

Drawing from this, if you do keep your phone on the charger, you don't have to really worry about it affecting your battery too much. The best case would be to eliminate draw (powering down phone, and thereby eliminating any need to recharge if the draw is higher than the charge), but this isn't really necessary - the difference is negligible. The major issue is extended periods of low/high battery charges - if you're going to leave your phone off for a month, try to keep it between 40-70% charge to minimize the degradation of capacity.

For more information, feel free to ask questions, or check out the pages I listed below.

Sources: I used to work in the cell phone industry. Lithium-based Batteries Information How to Prolong Lithium-based Batteries - Battery University

(note: i also posted this in a comment in the moto x subreddit)

EDIT:

TL;DR: Charge whenever possible. The lower the depth of discharge the more longevity, but it doesn't make a big difference either way.

EDIT2:

The lifespan of the battery (I probably should have put this up there, will edit) is also not rated to a 0% capacity rating - this is to 70% of the original capacity.

 

[metsnfins]

For older batteries this was indeed true.

For newer batteries it is no longer a requirement. The chargers and batteries on the new crop of phones will shut off and go into a trickle charge state (if needed) when they reach full capacity.

The only things you need to avoid doing too frequently are discharging the battery completely and letting it get too hot as these will both cause the charge capacity to deteriorate slightly over time.

You shouldn't let the battery run down?

 

[Serge58]

Mine gests overheated when the battery is full... WTF?

 

[iTzKPanda]

You shouldn't let the battery run down?

Technically yes, but you shouldn't worry about it.

 

[Scootmien]

You shouldn't let the battery run down?

Yes but this is only an advisory. Don't let it sweat you if the battery does run out completely on occasion; it's not going to b0rk your battery unless you constantly do it.