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Buzz Law

macrumors newbie
Original poster
Nov 16, 2008
17
0
I tend to leave my MBP connected to the charger even after its fully charged. Is there any harm in this?

I remember overcharging problems with cell phones, I'm not sure if the same rules apply.
 

vandozza

macrumors 6502a
Jun 14, 2006
612
0
Australia
towards the "end" of the charge cycle, you might notice that going from (say) 95% to 100% charged, is much slower than going from 90-95% charged (or any other 5% charge increase.)

the PMU slows down the rate of charging to a "trickle charge" towards the end of the charge cycle.

it's designed to do this to avoid any overcharge issues. it's perfectly safe to leave the power cord attached all the time (although at least monthly you should run the battery through a complete discharge/recharge cycle to promote battery health/life)
 

Buzz Law

macrumors newbie
Original poster
Nov 16, 2008
17
0
Thanks for the responses.

And Tallest Skill, you can definitely overcharge your cell phone battery.
 

iphonematt

Guest
Jul 10, 2007
190
0
Thanks for the responses.

And Tallest Skill, you can definitely overcharge your cell phone battery.

You can??? I have had many phones over the years and have never overcharged my battery. Most Lithium-Ion batteries will cut the power off when fully charged. My iPhone has been plugged in for days before and I never ran into a problem.
 

Shawn Parr

macrumors regular
Oct 31, 2008
191
97
Thanks for the responses.

And Tallest Skill, you can definitely overcharge your cell phone battery.

If your phone has a Lithium battery (i.e. LiION) this is unlikely, as overcharging them leads to fire and/or explosions.

Many batteries now contain logic inside the battery itself to help regulate the input and monitor the temperature to help keep that from happening.

Now if you have an older phone with an older type of battery (NiMH, NiCd, etc) yes you can overcharge them and it hurts their useful life.
 

skye12

macrumors 65816
Nov 11, 2006
1,211
2
Austin, Tx
You can't overcharge these batteries. However, it is recommended you
exercise the lithium ion batteries once a month by letting it run down.
You don't have to let it run all the way down either.
 
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