Published 2022-01-10 by TechNet New England
Laptop batteries degrade over time. After 2 to 3 years of regular use, a battery may hold only 80% of its original capacity. Here is how to check. ## Windows: Battery Report Windows can generate a detailed battery report. 1. Open **Command Prompt** (search for "cmd" in Start menu). 2. Run: ```cmd powercfg /batteryreport ``` 3. The report is saved as an HTML file, usually at `C:\Users\YourName\battery-report.html`. 4. Open the file in a browser. ### What to Look For **Design Capacity:** The battery's original capacity when new. **Full Charge Capacity:** The battery's current maximum capacity. **Cycle Count:** How many charge/discharge cycles the battery has been through. If Full Charge Capacity is less than 80% of Design Capacity, the battery is significantly degraded. Example: Design Capacity: 56,000 mWh Full Charge Capacity: 42,000 mWh This battery is at 75% health and should be considered for replacement. ## Mac: Battery Health ### Quick Check 1. Hold **Option** and click the **battery icon** in the menu bar. 2. It shows one of four conditions: **Normal:** Battery is functioning normally. **Replace Soon:** Battery holds less charge than when new. **Replace Now:** Battery holds significantly less charge. **Service Battery:** Battery may need to be serviced. ### Detailed Check 1. Click **Apple menu > System Settings > Battery**. 2. Click **Battery Health** (or the "i" icon). 3. It shows: **Maximum Capacity:** Percentage of original capacity remaining. **Cycle Count:** Available in Apple menu > About This Mac > More Info > System Report > Power. Apple considers a MacBook battery consumed after 1,000 cycles or when it drops below 80% capacity. ### Optimized Battery Charging Both Windows and Mac have features to preserve battery health: **Mac:** System Settings > Battery > Battery Health > Optimized Battery Charging. This learns your charging pattern and delays charging past 80% until you need it. **Windows:** Some manufacturers (Dell, Lenovo, HP) have similar features in their own battery management software. ## When to Replace Replace the battery when: Maximum capacity drops below 80%. The laptop shuts down unexpectedly even with charge remaining. The battery swells (the trackpad lifts, the case bulges). This is a safety issue. Stop using the laptop and contact IT or the manufacturer immediately. Battery life no longer lasts through a normal work session. ## When to Contact IT On managed devices, contact your IT provider for battery replacement. They can arrange warranty service (if applicable) or procure a replacement battery. Do not attempt to replace batteries in sealed laptops (most modern MacBooks, ultrabooks) yourself.