Ideal Maintenance For a MAC battery

Recently started using a MAC book air.

# MacBook Air (13-inch, 2017)

I love the battery life.

# Observation:

- Did notice that battery life is significantly less when I am developing (compiling / transpiing ) etc

- Compile time is more than a core 2 duo even though MAC is an i3 machine (by a few seconds ~3-5; again a qualitative analysis)

# Literature encountered so far:

https://apple.stackexchange.com/questions/17303/what-are-the-best-practices-for-battery-longevity

Summary:

# Temperature related degradation is the primary mode.

Arrhenius formula

for

# Battery capacity data for MACs of different ages and usage patterns:

- https://apple.stackexchange.com/a/17307

- https://apple.stackexchange.com/a/17305

- https://apple.stackexchange.com/a/43347

Summary - shows that most of the cited factors do not make a difference.

(but these might not be developer laptops where CPU intensive work happens - compile, transpile :P )

# nobody is discussing discharge rate related deterioration

(In my experience with Li-Po batteries with RC aircrafts; discharge current also plays an important role )

# but by the strict CPU under-clocking policy + SSD drives (no spinning hard disks ) + no fans (fans just create a resonant feedback loop :P)

I believe apple has managed to keep the current drawn well within the battery rating limit

(this is not entirely evidence based, somewhat speculative based on the comparative load / cpu activity observed on a dell core 2 duo machine vs a MAC)

# Another evidence that leads me to believe that above is the key:

https://www.apple.com/batteries/maximizing-performance/

Summary - They always ask to plug in the MAC to power source to charge other devices. Most likely to prevent a higher discharge rate for the battery

# Cites depth of discharge as the main factor that ages the battery (other than temperature)

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

# Just realised that current drawn and temperatures exposed to - sort of go hand in hand.

An official confirmation (of course not to a direct question about this.. )

The kernel_task process:

• https://support.apple.com/en-in/HT207359

Personal take:

• You would not notice this normally.
• But when you are compiling oh well, it becomes very noticeable.