Laptop battery draining fast: how to read the battery report and what you can change

Unplug the charger and switch the device off. Never puncture, bend or heat a swollen battery.

If the laptop case is lifting because the battery has expanded, stop using and charging that laptop.

There are two possibilities to tell apart. First, the battery capacity has really dropped. Microsoft writes that the capacity of lithium-ion cells goes down after the battery has been charged and run down many times, so the battery holds less charge than when it was new. Excessive heat speeds this up and reduces the capacity permanently.

Second, the battery is still healthy but the laptop uses more power than usual. The cause can be a bright screen, a screen that stays on a long time before the laptop sleeps, a high refresh rate, or apps that keep working in the background.

The Windows battery report helps you tell these two apart without any extra app. If the capacity has dropped a lot, settings will only help a little. If the capacity is still reasonable, the fix lies in your settings and usage habits.

The powercfg command is built into Windows. Microsoft's steps for Windows 11:

1. Select Start, type Command prompt, right-click the result, then choose Run as administrator and Yes.
2. Type powercfg /batteryreport, then press Enter.
3. The Command Prompt window shows where the report file was saved. The report is an HTML file.
4. Open File Explorer, go to that folder, then double-click the report file to open it in your browser.

Dell gives another route: press the Windows key and R, type cmd, then run the same command. That way, the battery-report.html file is saved in your user folder, for example C:\Users\your-name.

Microsoft Learn lists two extra options. The /output option sets the location and name of the report file, and the /duration option sets how many days of history go into the report.

Microsoft suggests starting with three sections: Installed batteries, Recent usage and Battery usage. On an Indonesian-language Windows they are called Baterai terpasang, Penggunaan terbaru and Penggunaan baterai. Dell adds the Battery life estimates section.

What matters most is how the two capacities compare. According to Dell, if Full Charge Capacity is below 40% of Design Capacity, the battery is significantly degraded and should be replaced. Dell also notes that Full Charge Capacity always shifts a little with temperature, the number of discharges to empty and the number of full charge cycles. A small gap from the design capacity does not mean the battery has a problem.

A common complaint: you close the laptop, put it in a bag, and later find much less battery left. Dell suggests checking the Recent usage section of the battery report to find periods of fast drain and apps that kept the laptop from sleeping. If that section shows the laptop as active at a time you are sure you were not using it, something is keeping it awake.

First check what happens when you close the lid. Microsoft writes that most laptops can go to sleep automatically when the lid is closed; set this through Control Panel, Power options, then Choose what closing the lid does. Do the same for the power button through Choose what the power buttons do, because that button can turn off the display, sleep, hibernate or shut the laptop down.

If you will not use the laptop for a long time, for example overnight in a bag, shut it down completely so no process uses the battery while it is stored. Do not put a laptop that is still running into a closed bag, because the heat gets trapped as well.

If the capacity is still reasonable, start with the settings. The menu names below follow Microsoft's support page for Windows 11 version 24H2 or later; older versions can differ.

• Energy recommendations: open Start, Settings, System, Power & battery, then Energy recommendations. Select Apply all, or adjust the settings that use more power than average one by one.
• Energy saver: on the same Power & battery page, set energy saver to turn on automatically when the battery falls to a certain level.
• Screen and sleep: choose shorter times for turning off the screen and putting the laptop to sleep on battery power.
• Brightness and refresh rate: lower the brightness, and choose a lower refresh rate in the advanced display settings.
• Background apps: open Battery usage on the Power & battery page, see which apps use a lot of battery in the background, then limit their background activity if the app allows it.
• Power mode: choose a more efficient power mode if your PC supports it.
• Video playback: under Apps, Video playback, select Optimize for battery life.

Microsoft suggests avoiding frequent deep discharges, and keeping the battery level between 20% and 80% when possible. If the laptop supports Smart charging, Microsoft suggests turning it on so the battery stays at the recommended level even if the laptop stays plugged in.

Some brands offer a similar feature in their own app. ASUS, for example, has the Battery Health Charging modes in MyASUS. Balance mode caps charging at 80%, and Maximum lifespan mode at 60%. This is useful for a laptop that almost always sits on a desk with the adapter connected.

Avoid using or charging the laptop in hot places, such as inside a car or an unventilated room at midday. For a laptop that will be stored for a long time, Microsoft suggests charging the battery to around 40 to 60%, neither full nor empty, then keeping it in a cool, dry place.

Take the laptop to the authorized service center for its brand if:

• the battery report shows Full Charge Capacity below 40% of Design Capacity, the threshold Dell uses for a battery that should be replaced;
• the laptop shuts down suddenly while the battery indicator still shows charge left;
• the bottom case, the keyboard or the touchpad looks raised. Microsoft says that if a battery expands beyond the device enclosure, you should stop using the device immediately, without pressing on or puncturing the battery;
• the battery gets very hot while charging or you smell a chemical odor.

Most laptops today use a built-in battery. Opening the battery pack, taking the battery apart or replacing the battery cells is a job for a technician, not something to do at home. Ask for a replacement battery that matches the laptop model, and back up your data before you hand the laptop in.