The short answer
Avoid charging to 100 per cent and avoid running it flat. Between about 20 and 80 per cent is where lithium batteries age slowest, and heat is the other thing that kills them.
- Use the optimised or limited charging setting if your phone has one. Most modern ones do.
- Avoid running it to zero regularly.
- Keep it cool. Do not leave it on a car dashboard, in direct sun, or charging under a pillow. Heat does more damage than charge cycles.
- Slow charging is gentler than fast charging where you have time, such as overnight.
- Check battery health in settings. Below about 80 per cent capacity, a replacement is worth considering.
What will ruin it
A swollen battery, a phone that will not sit flat or a screen lifting at the edge means stop using it and get it replaced immediately. Swollen lithium cells are a genuine fire risk and must not be punctured.
Why it works
Lithium cells age by two mechanisms: cycles and time at high state of charge, both accelerated by heat. Sitting at 100 per cent and warm is the worst combination, and that is exactly what charging overnight on a bed does.
Tipking is general household information, not professional advice. Test anything on a hidden patch first. Full disclaimer.
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