Every lithium battery wears out eventually, but how you use it affects how quickly. These habits help.
Keep it cool
Heat is the biggest enemy of battery health. Don't leave a laptop in a hot car, use it on a hard surface rather than a bed or couch, and keep vents clean.
Use built-in charge limits
Many laptops (including recent MacBooks, Lenovo, Dell, HP and ASUS models) offer a setting to stop charging at around 80% when you're usually plugged in. If you mostly work at a desk, turn it on.
Don't stress about full discharges
Modern batteries don't need to be run flat to 'calibrate'. Regularly draining to 0% actually adds wear. Topping up whenever it suits you is fine.
When to replace it
Replace the battery if it's swollen, if the laptop shuts down well before 0%, or if capacity has dropped so far that it no longer suits how you work.
- Windows: run 'powercfg /batteryreport' in Command Prompt to see design vs full charge capacity.
- Mac: System Settings → Battery → Battery Health.
- Any swelling: stop charging and get it checked promptly.