Signs Your Laptop Battery Is Failing and How to Recognize Them
- Christian Ordonez
- Nov 25
- 3 min read
A laptop battery that suddenly stops working can disrupt your day and cause data loss. Knowing the early signs of a failing battery helps you avoid unexpected shutdowns and plan for a replacement. This post explains the most common symptoms your laptop will show when its battery is about to go bad, so you can spot the problem before it becomes critical.
Battery Life Drops Quickly
One of the first signs of a failing battery is a noticeable drop in how long your laptop runs on a full charge. If your laptop used to last several hours but now dies after 30 minutes or less, the battery capacity has likely diminished. This happens because lithium-ion batteries lose their ability to hold charge over time.
For example, if you used to get 6 hours of use but now only get 1 or 2, it’s a clear warning. You can check your battery health on Windows by running the command `powercfg /batteryreport` in the Command Prompt or on macOS by holding the Option key and clicking the battery icon.
Unexpected Shutdowns or Restarts
When a battery is failing, it may not supply consistent power. This can cause your laptop to shut down suddenly, even when the battery indicator shows some charge left. These unexpected shutdowns happen because the battery voltage drops too low to keep the system running.
If your laptop restarts or powers off without warning, especially when unplugged, the battery is likely the culprit. This symptom is more common in older laptops or those exposed to extreme temperatures.
Battery Not Charging Fully
A failing battery often struggles to reach a full charge. You might notice the battery percentage stops increasing at 80% or 90%, or the charging icon switches between charging and not charging frequently. This behavior indicates the battery cells are degrading and cannot accept or hold a full charge.
Sometimes the laptop will say “Plugged in, not charging” even though the charger is connected. This message usually points to battery health issues or a faulty charging circuit.
Overheating and Swelling
Physical signs can also reveal battery problems. If your laptop feels hotter than usual during use or charging, the battery may be overheating. Overheating batteries degrade faster and can become unsafe.
In some cases, the battery may swell, causing the laptop case to bulge or the keyboard to lift. Swollen batteries are dangerous and should be replaced immediately to avoid damage or fire risk.
Battery Health Warnings from the Operating System
Modern laptops often include built-in diagnostics that alert you when the battery health is poor. Windows may show a warning in the system tray or in the battery settings. macOS displays a “Service Battery” message when the battery needs attention.
These warnings are based on battery cycle counts and health metrics. If you see such alerts, it’s time to consider replacing the battery.
Reduced Performance When Unplugged
Some laptops reduce CPU speed or limit performance when running on battery power to conserve energy. If you notice your laptop runs slower or apps take longer to load when unplugged, a failing battery might be the cause.
This happens because the battery cannot supply enough power for full performance, forcing the system to throttle resources.
How to Check Your Battery Health
You don’t have to guess if your battery is failing. Use built-in tools to check its status:
Windows: Open Command Prompt and type `powercfg /batteryreport`. This generates a detailed report showing battery capacity and cycle count.
macOS: Hold the Option key and click the battery icon in the menu bar. It will show battery condition such as “Normal” or “Service Recommended.”
Third-party apps: Tools like BatteryInfoView or CoconutBattery provide detailed battery health data.
Regularly checking your battery health helps you plan replacements before problems start.
What to Do When You Notice These Signs
If your laptop shows one or more of these symptoms, consider these steps:
Backup your data immediately to avoid loss during unexpected shutdowns.
Reduce battery strain by lowering screen brightness, closing unused apps, and avoiding heavy tasks on battery power.
Replace the battery if warnings persist or performance drops significantly. Using an original or certified replacement battery ensures safety and compatibility.
Consult a professional if you notice swelling or overheating to prevent damage.
Ignoring battery issues can lead to sudden failures and potential harm to your laptop.