Yes, MacBooks use lithium-ion batteries, not lithium metal

Every MacBook sold since 2008 contains a lithium-ion (Li-ion) battery, not a lithium metal battery. Lithium-ion is the rechargeable chemistry that powers nearly all modern laptops, phones, and tablets. It stores more energy in a smaller space than older battery types and can be recharged hundreds of times before capacity drops noticeably.

Apple does not publish the exact lithium content of individual MacBook models, but the battery chemistry is lithium-ion across the entire MacBook line — MacBook Air, MacBook Pro, and the older 12-inch MacBook. The capacity varies by model year and screen size, measured in watt-hours (Wh), but the underlying chemistry is the same.

Key Takeaways

  • MacBooks use lithium-ion batteries, which are rechargeable and designed to last 300 to 500 full charge cycles before capacity drops to 80 percent.
  • Battery capacity is measured in watt-hours and ranges from about 45 Wh in smaller MacBook Air models to 100 Wh in larger MacBook Pro models.
  • Lithium-ion batteries degrade over time and with use; Apple's battery service replaces them when capacity falls below 80 percent of original.
  • You can check your current battery health in System Settings under Battery, which shows maximum capacity as a percentage of the original.

How MacBook battery capacity is measured and what the numbers mean

MacBook batteries are rated in watt-hours (Wh), a measure of total energy storage. A larger Wh number means longer runtime between charges, all else equal. A 52 Wh battery will run longer than a 45 Wh battery in the same machine, though the difference depends on what you are doing — video playback drains faster than web browsing.

Current MacBook Air models typically carry 45 Wh to 52 Wh batteries depending on screen size. MacBook Pro models range from 70 Wh to 100 Wh. Older models from 2015 to 2019 often had 54 Wh to 83 Wh. You can find your exact battery capacity by holding Option and clicking the battery icon in the menu bar, or by going to System Settings, then Battery, then Battery Health & Condition.

Why lithium-ion degrades and what affects battery lifespan

Lithium-ion batteries lose capacity every time they charge and discharge. After 300 to 500 full cycles, most lithium-ion batteries retain about 80 percent of their original capacity. A "cycle" means draining the battery fully and recharging it completely — using 50 percent and recharging counts as half a cycle.

Heat accelerates degradation. Leaving your MacBook in a hot car, using it on a bed or pillow that blocks vents, or running intensive tasks in warm rooms all speed up capacity loss. Keeping your MacBook cool and avoiding full discharges every day extends battery life. Charging to 80 percent and stopping there, rather than charging to 100 percent daily, also slows degradation, though MacBooks do not have a built-in limit for this.

Storage also matters. A MacBook left unplugged for months will lose charge and may not power on. Lithium-ion batteries stored at 50 percent charge in cool conditions degrade more slowly than those stored fully charged or fully drained.

How to check your MacBook battery health right now

Open System Settings and navigate to Battery. Click Battery Health & Condition. You will see your current maximum capacity as a percentage — for example, "85% of original capacity." You will also see the condition status: Normal, Replace Soon, Replace Now, or Service Recommended.

If the status says Normal, your battery is fine. If it says Replace Soon or Service Recommended, the battery is still usable but losing capacity faster than normal. If it says Replace Now, the battery is degraded enough that Apple recommends replacement. You do not have to replace it when ready — the machine will keep working — but performance and runtime will decline.

You can also check battery cycle count using the System Report. Hold Option, click the Apple menu, select System Information, then click Power. Look for "Cycle Count" — this is the total number of charge cycles your battery has completed. Compare this to the design cycle rating (usually 300 to 500) to estimate remaining lifespan.

When and how to replace a MacBook battery

Apple offers battery replacement at Apple Stores and Apple Authorized Service Providers. The cost varies by MacBook model but typically ranges from $129 to $199 for parts and labor. Some older models may cost less; newer models with larger batteries may cost more. Prices differ by region and provider.

If your MacBook is still under warranty or covered by AppleCare+, battery replacement is covered if capacity has dropped below 80 percent. Outside warranty, you pay out of pocket. The replacement usually takes one to three business days, though some locations can do it same-day if parts are in stock.

Third-party repair shops also offer MacBook battery replacement, often at lower cost than Apple. Quality and warranty coverage vary widely. If you choose a third-party service, verify they use genuine or certified batteries and offer a warranty on the replacement.

What happens if you ignore a degraded battery

A MacBook with a degraded battery will still work, but runtime between charges shrinks. A machine that once ran eight hours on a charge might run four or five hours as capacity drops. The machine may also shut down unexpectedly when the battery reports it is empty but still has a small charge left — this is a sign of advanced degradation.

Degraded batteries can also cause the MacBook to throttle performance or refuse to start if the battery voltage drops too low. In rare cases, a severely degraded battery can swell and damage the trackpad or keyboard. If you see the trackpad or keyboard bulging, stop using the machine and take it to a service provider when ready.

Frequently Asked Questions

Can I replace a MacBook battery myself?

Most modern MacBooks have batteries glued to the case, making self-replacement difficult without damaging the machine. Older models (pre-2016) had user-replaceable batteries. If you are not comfortable with hardware repair, professional replacement is safer and comes with a warranty on the work.

Does leaving my MacBook plugged in all the time damage the battery?

No. Modern MacBooks stop charging at 100 percent and switch to trickle charging, which prevents overcharging. Leaving it plugged in continuously is safe, though the battery will degrade slightly faster than if you occasionally let it discharge to 50 percent.

Why does my MacBook battery drain fast even though it is new?

New MacBooks sometimes show lower-than-expected battery life because background processes are indexing files, updating apps, or syncing data. This settles after a few days. If drain remains high after a week, check Activity Monitor to see which apps are using the most CPU and energy, then close or uninstall the culprits.

Is it safe to use my MacBook while it is charging?

Yes, it is safe. Using your MacBook while plugged in does not damage the battery. The charger supplies power directly to the machine, and the battery management system prevents overcharging. The machine may run warm during intensive tasks while charging, but this is normal.

What is the difference between cycle count and age?

Cycle count measures actual charge-discharge events; age measures calendar time. A MacBook used heavily for one year might have 300 cycles, while one used lightly for three years might have 150 cycles. Cycle count is a better predictor of remaining battery life than age alone, though both matter.