Signs Your Phone Battery Needs Replacing

1. Your battery drains faster than it used to

If your phone used to last a full day and now needs a top-up by lunchtime, that's the clearest signal. Lithium-ion batteries degrade with every charge cycle — after 500–600 cycles, most are sitting at 80% of their original capacity or below. You're not imagining it. The battery is genuinely holding less charge.

2. Your phone shuts off before it hits 0%

An aging battery can no longer sustain the voltage spike that demanding tasks require. When your phone does something intensive — launching an app, taking a photo, connecting to a new network — the battery voltage drops suddenly. The phone interprets this as empty and shuts down, even if the display showed 20% a moment ago.

This is particularly dangerous in cold weather. Low temperatures reduce battery output even further, which is why phones die faster on a ski hill or a winter walk.

3. The phone runs hot doing normal things

A degraded battery has higher internal resistance. That resistance converts electrical energy into heat instead of useful power. If your phone gets noticeably warm just browsing or streaming — not gaming, not charging — that warmth is often coming from an inefficient battery working harder than it should.

4. The back of the phone is bulging

This one is urgent. A swollen battery is caused by gas build-up inside the cell — a byproduct of chemical breakdown. The battery is physically expanding and pressing against the case. On iPhones you'll notice the screen lifting slightly from the frame. On Android phones the back cover may bow outward.

5. iOS has enabled performance throttling

Apple introduced performance management in iOS 11.3 to prevent unexpected shutdowns on phones with degraded batteries. The phone automatically reduces processor speed to stay within what the battery can deliver. The side effect: everything feels slower — apps take longer to open, the keyboard lags, animations stutter.

If your iPhone says "Performance Management Applied" under Battery Health, your battery is the reason your phone feels sluggish. A new battery will restore full performance.

6. The percentage jumps around erratically

If your battery drops from 40% to 15% in minutes, then sits at 15% for an hour, then jumps back to 30% after a rest — the battery's internal sensor is no longer accurate. The cell's chemistry has degraded to the point where it can't reliably report its own state. This makes the phone genuinely unpredictable.

How long does a battery replacement take?

For most iPhones and Android flagships, a battery replacement takes 30–45 minutes. We test battery health before and after, and you'll leave with a battery showing 100% capacity. The repair includes a 90-day warranty on the new cell.