Is Your Laptop Battery Dying? Signs, Tests, and Solutions

Every rechargeable battery has a finite lifespan measured in charge cycles. After 300–500 complete charge cycles, most laptop batteries have degraded significantly. Here's how to check yours and what to do about it.

Signs your battery needs replacing

• Battery life has dropped significantly from new (e.g. was 6 hours, now 90 minutes)
• The laptop dies suddenly without warning at 20–30% battery
• The battery percentage drops rapidly (from 60% to 10% in minutes)
• The laptop only works when plugged in
• Windows shows a "Consider replacing your battery" warning
• The bottom of the laptop is bulging (swollen battery — replace immediately)

How to check battery health on Windows

Open Command Prompt as administrator and type: powercfg /batteryreport then press Enter. This generates a battery report saved to your user folder. Open it in a browser. Look for "Design Capacity" vs "Full Charge Capacity" — if Full Charge is significantly below Design Capacity (e.g. less than 60%), your battery has significantly degraded.

Is a battery replacement worth it?

For most laptops under 7 years old, yes. A new battery typically costs £40–£70 including fitting, and gives you a completely restored battery life. It's far cheaper than a new laptop. For very old machines, it's worth considering whether the laptop is worth keeping at all — Darren can give honest advice on this.