Lemme shed more light on Li-ion/Li-polymer batteries.

BTW I'm new in this thread.

Our macbook's use Li-polymer, which is basically the same as Li-ion but is not round therefore you can have more capacity per volume(if cells are cubic in nature). Li-ion's are basically round cells and therefore have less capacity per volume.

Li-ion's have 3 enemies. Heat, time and (strangely) capacity.
Hotter = die faster
Longer = die faster
The more charge it has = die faster (to a point only)

Storing @ 30ºC for 1 year, your battery will lose it's capacity faster than @10ºC for 1 year if both are at equal charge.
Storing @ 100% charge for 1 year, your battery will lose it's capacity faster than @50% charge for 1 year if both are at equal temperature.
And of course, storing for 1 year, your battery will lose it's capacity faster than storing for 6 months if both are at equal temperature.

Li-ion seems happiest @ 40% charge, low temperatures.
Also, li-ion seems to not like cycling 0%>100%>0%

Oh well...

Someone correct me if I'm wrong anywhere.



Oh ya. Forgot my battery. Just ran a cycle a week ago I think.
Ori capacity: 5020 mAh
Current capacity: 94%(4731 mAh)
Loadcycles: 261
Age of Mac: 21 months
Pretty good I'd say.

This post has been edited by polkiuj: Sep 23 2009, 10:10 AM

Keeping the battery @ 100% will kill it faster. See post #256. I've explained the behaviour of li-ion.polymer cells.


Unfortunately it should read good. Maybe apple changed, i dunno. Try downloading coconut battery to check it's capacity.
It should read something like



To shed more light, calibrating WILL NOT increase the capacity or maintain it. (No matter what apple says)

The purpose of calibration is to reset your macbook's battery meter so that it is accurate. Hence the term "calibration"

In fact, calibration will usually decrease battery's capacity by a little bit as lithiums do not like to be over-discharged.



Here's my battery few days after calibration.
Hmm... can't upload.. oops.
Type out la.

Current cap. = 4668 mAh
Ori cap. = 5020 mAh
Capacity left = 92%

Load-cycle = 313
Age = 24 months

Hey not bad =P

Sorry, there is no way to regain lost capacity on Lithium batteries as the chemistry is like that. Only option is to get a new battery.

You should check if your battery is really at that capacity though as it is un-naturally low. It should be more than 50% still. Is this after a calibration? An uncalibrated reading might not be accurate as some charge can be lost during the charging/discharging process.


Yes it will ruin the batt if you keep it full all the time. This is just the way Lithium batteries work.
Battery life depends on what you do.

If you want to leave your MBP at home all the time, I suggest you get a desktop.

If you really want to maximize your battery life, there is one way.
Discharge it to 40%. Then store it in ur fridge. 40% seems to be the optimal capacity to store a Li-ion based battery and the lower the temp, the better. Not too low like freezer. Fridge should be fine.


Yes, keeping it full will kill it faster.

And please, Acer and all other companies battery work the same. Even the charging algorithm is the same as Lithium cobalt based batteries are very explosive prone and is not happy with weird charging algorithms. If charge is not cut by the time the batt reaches 100%, it will (soon) overheat and blow up. *BOOM*

Acer and all other companies do have a separate problem though. The battery is usually kept together with all other heat producing components. So the battery will naturally not last as long. Apple (being the genius they are) has kept the battery far away from all the "battery assassins". Therefora a mac battery usually lasts much longer. Hooray to Apple! =D


Here's my batt.
Hmm... it refuses to let me upload.. =(

Charge Information:
Charge remaining (mAh): 2409
Fully charged: No
Charging: No
Full charge capacity (mAh): 4636 (of 5020, 92%)
Health Information:
Cycle count: 318 (age: 24 months)
Condition: Good
Battery Installed: Yes
Amperage (mA): -1387
Voltage (mV): 11236

This post has been edited by polkiuj: Jan 4 2010, 12:14 PM

haih.. still won't let me post pic... =(

This post has been edited by polkiuj: Jan 13 2010, 03:41 PM