A trackpad that clicks poorly, a case that bulges, a chassis that no longer sits flat: it’s often a swollen battery. This isn’t a failure like any other — you need to act fast, but calmly. Here are the right reflexes, and what a replacement really costs.
A swelling battery produces gas inside its lithium cells: it’s chemical ageing, not a lack of care. The right response comes down to three steps: stop charging, never press or puncture, replace quickly. A swollen battery never “deflates” — and the longer you wait, the harder it presses on the trackpad, the keyboard and the case. It can’t be repaired, but it can be replaced very well indeed.
The battery is hidden under the chassis: you rarely see it swell directly. It’s the parts around it that do the talking.
It’s the most common symptom: the battery sits right under the trackpad. When its cells swell, they push it upwards — the click becomes stiff, inconsistent, or stops responding altogether.
Test: lay a ruler across the trackpad — if it sits proud of the case, something is wrong.The MacBook rocks on a flat table, the bottom case is visibly bowed, or the screws seem under strain. Internal pressure is deforming the chassis — this is already an advanced stage.
A sudden drop in battery life, shutdowns at 30%, or a “Service Battery” / “Service Recommended” message in macOS often go hand in hand with swelling — the battery’s chemistry is at the end of its life.
Check: menu > About This Mac > System Report > Power — look at the cycle count and condition.In the most advanced cases, the pressure reaches the keyboard (keys that rub) and can even go as far as marking the screen when the Mac is closed. At this stage, every day counts: the battery is endangering parts far more expensive than itself.
A swollen battery is not a bomb — incidents are rare. But pressurised lithium forgives neither puncturing nor crushing. In order:
Lithium-polymer cells age with every charge cycle. Over time — and faster with heat, permanent charging or an unsuitable charger — the electrolyte degrades and releases gas. The cell’s soft pouch stretches like a cushion: that’s the swelling. It is irreversible and keeps progressing as long as the battery stays in service. It’s not a matter of brand or bad luck: every lithium battery ages eventually — a MacBook’s like any other.
Our batteries are new (never second-hand when it comes to lithium), tested, with a 2-year warranty, from €30 incl. VAT depending on the model. To find the right part:
On recent models, the battery is glued to the chassis and removing it takes tools and experience — especially once it has swollen. Our Paris workshop takes care of it:
“As long as the Mac still works, a swollen battery can wait.”
Swelling always progresses. While you wait, the battery presses on the trackpad (which isn’t free to replace), warps the case, and can end up marking the screen. Replacing a battery in time means protecting every part around it — waiting turns a simple job into multiple repairs.
Stop charging, don’t force anything, and replace it without delay: a new, tested battery with a 2-year warranty, fitted by you or by our Paris workshop. Your trackpad, your keyboard and your screen will thank you.
Best not to. Every charge cycle makes the swelling worse, and the pressure gradually damages the trackpad, the keyboard and the case. If you absolutely must use it while waiting for the replacement, keep it brief and watch for any new deformation.
The risk of an incident is low as long as it isn’t mistreated, but it’s real in case of puncturing, crushing or strong heat. Never pierce it, don’t try to flatten it, keep it away from heat sources and hand it over to a recycling channel — not the household bin.
The battery alone starts at €30 incl. VAT at Place du Mac, depending on the Mac model (recent models cost more). For a workshop fitting, add the labour — the details are on our pricing page. Either way, it’s far below the price of the parts that swelling would eventually damage.
All our batteries are new and tested, with a 2-year warranty. Lithium ages chemically: a “second-hand” battery would make no sense — it’s actually one of the few parts we don’t offer in grades.
Turn your Mac over: the model number (A2338, A1502, A2141…) is engraved on the bottom case. Our battery pages list compatibility by model number and year — if in doubt, contact us with that number and we’ll confirm the right part.
It’s not a maintenance mistake: it’s the normal ageing of lithium chemistry, accelerated by heat, age and cycle count. A Mac left plugged in for years, or used on heat-trapping surfaces (a duvet, a sofa), ages its battery a little faster.
A Place du Mac guide — new, tested batteries, 2-year warranty, repair workshop at 51 rue du Faubourg Poissonnière, Paris 9th. Swollen lithium batteries must be handled with care and recycled through an appropriate channel. Apple, Mac and MacBook are trademarks of Apple Inc.; Place du Mac is an independent repair shop, not affiliated with Apple Inc.
