• MacBookAir4,2 Mid 2011: MC965LL/A (1.7 GHz Core i5)
• MacBookAir4,2 Mid 2011: MC966LL/A (1.7 GHz Core i5)
• MacBookAir4,2 Mid 2011: MD226LL/A (1.8 GHz Core i7)
• MacBookAir5,2 Mid 2012: MD231LL/A (1.8 GHz Core i5)
• MacBookAir5,2 Mid 2012: MD232LL/A (1.8 GHz Core i5)
• MacBookAir5,2 Mid 2012: MD232LL/A (2.0 GHz Core i7)
• MacBookAir5,2 Mid 2012: MD846LL/A (2.0 GHz Core i7)
• MacBookAir5,2 Mid 2012: MD846LL/A (2.0 GHz Core i7)
• Apple Part #: 661-6055, 661-6639
• Printed Part #: 020-7379-A
• Printed Model #: A1405

Mac.Infinity Tips

How to prevent swollen battery?

• Keep the battery cool for the most part – in other words, keep it within regular laptop operating temperatures. Don’t store it in the sun or use it plugged in for long periods of time in the sun.

• Use the right capacity Apple charger or quality third-party manufacturer charger.

• Don’t leave the laptop constantly plugged in when it doesn’t need to be.

• Replace old batteries that are not holding their charge anymore.

Battery Installation by Mc.Infinity 

https://www.macinfinity.sg/macbook-battery-replacement