Why is charge remaining already so much lower than full charge capacity on a brand new MBP? It is fully charged.
Charge Information:
Charge Remaining (mAh): 7199
Fully Charged: Yes
Charging: No
Full Charge Capacity (mAh): 7430
Health Information:
Cycle Count: 2
Please read:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Note that there are 3 numbers that are important on your Macbook:
Charge Remaining (mAh): 3817
Full Charge Capacity (mAh): 6980mAh
Design Capacity (mAh): 7000mAh
The Full charge / Design capacity is a measure of your battery wear level.
Charge remaining shows the current state of charge.
LiIon degrades when kept at 100% charge - especially when subject to heat (i,e, in your computer). Max cycle count (number of cycles that the battery can undergo whilst still maintaining say 80% Full Charge compared to Design Capacity) is therefore improved when the battery is kept charged at a level below it's nominal max (i.e. cell voltages below 4.2V and closer to 4.1V).
The avoid the general public asking this question the normal % status will show 100%, when in reality it's 5-10% below this.
Trust me - I want all manufacturers to do this - much better to have 500-1000 cycles with a 90% capacity battery than 1 years worth of 100% and then battery replacement.
The first time I came across this undercharging was with a 2007 Thinkpad - you could tell it not to charge if the battery was at, say 80-90%. That Thinkpad battery is *still* at 90% full charge capacity.
L (senior member IEEE)
Edit: I will just add to echo Lennyvaletin's comment: remaining charge and full charge capacities are given to a higher level of precision than is warranted. Typical accuracy is to a few percent (not to the last mAh) (
https://www.maximintegrated.com/en/app-notes/index.mvp/id/3958)
