When to Replace Your iPhone Battery: Health, Performance, Swelling

Every iPhone battery wears out eventually. Lithium-ion batteries lose capacity each time they are charged and drained, so a phone that lasted all day when it was new may struggle to reach mid-afternoon a few years later. The good news: a battery is one of the most common and straightforward iPhone repairs. Here is how to know when an iPhone battery replacement makes sense, and the warning signs you should never ignore.

Check Battery Health in Settings

Your iPhone keeps track of its own battery condition. To see it:

1. Open Settings.
2. Tap Battery.
3. Tap Battery Health (on some iOS versions it is labelled Battery Health & Charging).

You will see a Maximum Capacity percentage. This compares your battery's current capacity to when it was new. As it drops, you get less use per charge. When the battery is significantly degraded, iOS may show a message recommending service. Around 80% or lower is generally the point where most people start to notice the difference in daily use.

What "Peak Performance Capability" means

Below Maximum Capacity you will find a line about Peak Performance Capability. A healthy battery shows that it supports normal peak performance. If your iPhone has experienced an unexpected shutdown because the battery could not deliver enough power, iOS may turn on performance management. This reduces peak performance to prevent more shutdowns.

In practice, that can feel like:

• Apps opening more slowly.
• Lower frame rates while scrolling or gaming.
• Dimmer screen brightness or lower speaker volume at times.

Replacing the battery typically restores normal performance, which is why a battery swap can make an older iPhone feel much quicker again.

Everyday signs your iPhone battery is wearing out

Even without opening Settings, you will often notice:

• Sudden shutdowns at 20%, 30% or more, especially in the cold. Ottawa winters are hard on tired batteries; see how cold weather affects phones.
• Fast draining even with light use.
• The percentage jumping, for example from 40% to 10% in minutes.
• The phone only working while plugged in.
• The phone getting warm during simple tasks or while charging.

Before blaming the battery, it is worth ruling out software causes such as a misbehaving app. Our guide on phone battery draining fast covers what to try first.

Swollen battery: stop using the phone

A swollen battery is a safety issue, not just a performance one. Signs include:

• The screen lifting or separating from the frame.
• A visible gap along one edge of the phone.
• The phone rocking when laid flat on a table.
• The display showing pressure marks or the touch acting strangely.

If you suspect swelling:

1. Stop charging it right away.
2. Do not press the screen back into place.
3. Never try to puncture, cut or pry out the battery yourself.
4. Keep the phone away from heat, pockets and bedding, and have it looked at by a technician as soon as possible.

What to expect from a professional battery replacement

A proper iPhone battery replacement involves opening the phone, disconnecting the battery safely, removing the old battery's strong adhesive without bending it, installing the new cell and resealing the phone. Back up your iPhone before the repair; the procedure should not touch your data, but it is always the safe move. On some newer models, iOS may show a message about the battery part after a replacement, so ask about it beforehand.

iPhone battery replacement in Ottawa — we come to you

Fix Revolution has been repairing phones for more than 10 years. We pick up your iPhone at home or at work anywhere in Ottawa and Gatineau, from Barrhaven to the Glebe, replace the battery, and drop it back off. Most repairs are done the same day, depending on parts availability, and they come with a 90-day warranty on parts and labour.

See our full range of iPhone repair services, then get a free quote or call 613-265-4349 to set up a pickup.

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