5 Signs Your Phone Battery Needs Replacing
Every phone battery wears out eventually — it's a chemical cell, not a switch, and it degrades a little every time you charge it. The question isn't whether it'll happen, it's whether you can spot it before it starts actually disrupting your day.
1. It doesn't last as long as it used to
The most obvious sign, and the one most people wait too long to act on. If a full charge used to get you through the day and now it's gone by mid-afternoon with the same usage, the battery's capacity has shrunk. Most phones let you check this directly: on iPhone, it's Settings > Battery > Battery Health, and on Android it's usually in Settings > Battery > Battery Health or a similar menu depending on the manufacturer. Anything below about 80% capacity is worth acting on.
2. It switches off suddenly, even with charge left
If your phone shows 20–30% battery and then shuts down without warning, that's a strong sign the battery can no longer deliver power steadily under load — a classic symptom of a worn-out cell, not a software issue.
3. It's slower than it used to be
Some phones deliberately slow themselves down when the battery can't supply peak power reliably, specifically to prevent unexpected shutdowns. If your phone feels sluggish and a battery health check shows reduced capacity, the slowdown and the battery are very likely connected.
4. It takes much longer to charge
A battery that's degrading often also charges less efficiently, taking noticeably longer to reach 100% than it did when new, even with the same charger and cable.
5. It gets warm during normal use
A phone that runs warm just sitting in your pocket, not while gaming or on a call, can be a sign the battery is working harder than it should to hold a charge.
The one sign that means stop using it now
If the back of your phone is visibly bulging, or the screen is lifting away from the frame at the edges, that's a swollen battery — a genuine safety issue, not just an inconvenience. Stop using it, don't puncture or bend it, and bring it in straight away.
Battery replacements start from £29, we check battery health for free with no obligation, and most are done same day.