MacBook Air 2019: Swollen Battery and Trackpad Failure
Overview
A teacher from Cherrybrook noticed their MacBook Air's trackpad had stopped clicking properly. They could still tap-to-click but physical clicks didn't register. Additionally, the bottom case appeared slightly raised. These symptoms pointed to a swollen batteryâa condition requiring prompt attention for safety reasons.
Initial Symptoms
- Trackpad wouldn't physically click (tap-to-click still worked)
- Bottom case visibly bowedâwouldn't sit flat on a table
- Slight gap visible between bottom case and chassis
- Battery cycle count: 847 (approaching end of rated lifespan)
- macOS Battery Health showed "Service Recommended"
- Mac had been in regular daily use for 5 years
Diagnostic Process
Why Batteries Swell
Lithium-ion batteries contain cells that can produce gas as they degrade. This gas buildup causes the battery pouch to expand. Contributing factors include:
- Age: Chemical degradation over time
- Heat exposure: Accelerates degradation
- Deep discharge cycles: Running battery to 0% regularly
- Manufacturing variations: Some cells more prone than others
Visual Confirmation
Upon removing the bottom case, we confirmed significant battery swelling:
- Battery cells visibly expandedâpushing against bottom case
- Trackpad force click mechanism blocked by battery expansion
- No puncture or damage to battery pouch (important for safety)
- No corrosion or liquid damage visible on logic board
Safety Assessment
Swollen batteries are a safety concern but not an immediate emergency if handled properly. This battery showed moderate swelling with intact pouchâsafe to remove with proper technique. We advised the customer to avoid using the Mac until repair was complete.
Repair Process
Battery Removal Challenges
MacBook Air 2019 batteries are adhesive-mounted, requiring careful removal:
- Disconnected battery from logic board first (critical safety step)
- Applied adhesive remover to battery tabs
- Used plastic pry tools to gently separate battery from case
- Worked slowly to avoid puncturing swollen cells
- Complete removal took approximately 30 minutes
Inspection
With battery removed, we inspected for secondary damage:
- Trackpad assembly: No permanent deformation
- Logic board: No pressure damage visible
- Display cables: Not affected
- Case: Minor flexing, returned to normal when battery removed
New Battery Installation
- Installed quality replacement battery (5113mAh, matching original spec)
- Applied fresh adhesive strips
- Connected to logic board
- Verified proper seating and connection
Testing
- Battery recognised by macOS immediately
- Charged to 100% without issues
- Battery Health showed "Normal"
- Trackpad clicking fully restored
- Bottom case sat flat again
Outcome
The teacher's MacBook Air was returned to full functionality. The new battery provides expected 10-12 hours of use, and the trackpad works perfectly. We disposed of the swollen battery through proper electronic waste recycling.
Key Takeaways
- Trackpad issues often indicate battery problems: The trackpad sits directly above the battery. Swelling pushes up and blocks the click mechanism.
- Swollen batteries need prompt attention: While not immediately dangerous, they shouldn't be ignored or used.
- Visual signs are clear: A bowed bottom case, raised keyboard edges, or trackpad issues are telltale signs.
- Don't attempt DIY on swollen batteries: Risk of puncture and thermal event. Professional removal is safer.
- 5-year-old batteries are often due: This Mac was within expected battery lifespan limits.
Trackpad Not Clicking? Battery Concerns?
If your MacBook's trackpad isn't clicking properly or you suspect battery swelling, prompt assessment ensures safe handling. We can replace swollen batteries safely and restore full functionality.