5 signs your iPhone battery needs to be replaced

Unexpected shutdowns

One of the clearest signs of battery degradation is when an iPhone suddenly shuts down even though it still shows remaining charge.

As batteries age, internal resistance rises and the phone may no longer receive stable voltage during processor-intensive tasks. To protect its circuitry, the device may switch off unexpectedly, according to tech site BGR.

Battery Health below 80%

Apple allows users to monitor battery condition through the Battery Health feature, which shows how much charge the battery can hold compared with when it was new.

The company recommends replacing the battery once maximum capacity falls to 80% or lower. At that point, the phone may require more frequent charging or become less responsive during demanding tasks because the aging battery can no longer deliver stable power, according to tech site MacObserver.

An iPhone charging on a wireless charger. Photo from Pexels

Battery drains unusually fast

A battery that loses charge much faster than before often signals chemical aging. Even with moderate use, the phone may require multiple charges throughout the day.

While screen brightness, background apps or heavy usage can contribute to faster drain, persistent rapid battery loss usually indicates the battery itself has worn out.

Slow charging

If an iPhone takes far longer than usual to charge, the battery may be deteriorating.

Before assuming a battery problem, users should check for faulty cables, damaged adapters or debris in the charging port. If the issue persists, the battery is likely nearing the end of its lifespan.

Swollen battery

Physical swelling is a serious warning sign that requires immediate attention. A swollen lithium-ion battery can push against the screen or back panel and may pose a fire risk.

In some cases, an aging battery may also cause the phone to overheat during normal use because it delivers power inconsistently.

While battery aging cannot be prevented, experts recommend steps to slow the process, including avoiding extreme temperatures, keeping the device between 0 and 35 degrees Celsius, enabling Optimized Battery Charging feature, avoiding constant charging to 100%, and regularly updating the iOS operating system.