Maintenance
Laptop battery replacement: how to know it is actually time
Batteries wear out gradually, so most people replace them either far too early or long after they stopped being useful.
A laptop battery replacement is one of the few repairs you can judge for yourself with real numbers. Windows records exactly how much capacity your battery has lost, and getting at it takes about thirty seconds.
Run the battery report first
Open Command Prompt and type powercfg /batteryreport, then press Enter. Windows writes an HTML file and tells you where it saved it. Open that file in your browser.
Look for two figures near the top: design capacity and full charge capacity. Design is what the battery held when new. Full charge is what it holds today.
Divide one by the other. Above roughly 80 percent is healthy. Between 60 and 80 you will notice shorter runtime. Below 60, replacement is reasonable.
When it is not the battery at all
Plenty of machines booked in for a laptop battery replacement turn out to have a failing charger or a worn charging port instead. The symptoms overlap almost completely.
So test the adapter before ordering anything. Our guide to a laptop not charging walks through separating the three faults in a few minutes.
Signs you should act on immediately
A swollen battery is not a wait-and-see problem. If the trackpad has started to lift, the case is bowing, or the laptop rocks on a flat table, stop using it and unplug it.
Swelling means the cells are venting gas. Guidance from the Consumer Product Safety Commission is worth reading, but the short version is: do not charge it, do not press it, and get it replaced.
Making the next one last
Heat ages batteries faster than charge cycles do. Therefore a laptop that runs hot on a bed or a sofa is quietly shortening its own battery life every day.
If your model supports a charge limit, setting it around 80 percent for desk use meaningfully extends lifespan. Many ThinkPad and IdeaPad machines offer this in Lenovo Vantage.
Keeping the cooling clear helps too, which is covered in our piece on laptop overheating.
Which battery to fit
Cell quality is where cheap batteries cost you, both in runtime and in safety. As a Lenovo authorised partner we use genuine cells for those machines. The difference between part tiers is explained in our guide to Lenovo parts.
Battery not lasting an hour?
Run the report, then bring it in. We test the charger and port too.