How to Test a Laptop Battery

A laptop battery provides power for a laptop when it is not plugged into a power source. The laptop battery is in the laptop. The power cord that charges a laptop battery is called the AC Power Adapter. The laptop battery can only power the laptop for a limited amount of time before the battery loses power and has to be recharged with the AC Power Adapter.

 

The length of time the laptop battery lasts mostly depends on the applications and programs the user runs on the laptop. Other factors that affect battery life are battery age, size, type, and use. There are a few different tests to estimate of how long a battery lasts and to see if it is time to replace the battery.

 

Test the Battery via Percentage

The amount of time remaining on a laptop battery can be measured by the battery icon on the taskbar at the bottom right corner of the laptop screen. Most laptops only give the percentage of time remaining and not the specific amount of time left before the battery dies.

 

Follow these steps to test the laptop battery usage percentage:

 

1. Plug the AC Power Adapter into an electrical outlet, then insert the other end into the laptop.
2. Leave the AC Power Adapter in the laptop for 4 to 8 hours to allow it to fully charge the battery. Make sure the laptop is not on while the battery is charging.
3. Remove the AC Power Adapter from the laptop, then turn the laptop on.
4. Record the amount of time it takes for the battery to use all of its power and shut down. Be sure to record from the time the AC Power Adapter was taken out to the time the laptop battery dies. The time estimate will be more accurate if the programs and applications normally used are run on the laptop during this test. For example, if the user typically checks e-mail, plays YouTube videos, and uses Facebook applications, those tasks should be performed while recording the battery life.
5. Repeat Steps 1, 2, and 3.
6. Hover the mouse over the battery icon that is on the taskbar at the bottom right of the laptop screen. When this is done, a small box will come up and state the percentage of battery power remaining.
7. Now the user can convert the percentage of battery power remaining to a time estimate. For example, if the battery ran for 4 hours before dying when tested and the battery icon says that the battery has 50% power remaining, then the battery will last for approximately 2 more hours. That same battery will last approximately 1 hour at 25%.

 

Test Whether Battery Should be Replaced with Battery Icon

In order to test whether a laptop battery should be replaced, follow some simple steps to test the battery’s performance.

 

To use the battery icon to test whether the laptop battery should be replaced, follow these steps:

1. Follow Steps 1-3 above to fully charge the laptop battery and turn the computer on.
2. Hover the mouse over the battery icon on the taskbar at the bottom right side of the screen. Make sure the laptop battery is charged to 100%.
3. Unplug the AC Power Adapter for 10 minutes and leave the laptop running. During these 10 minutes, run any applications or programs typically used on the computer.
4. After the 10 minutes are up, check the percentage on the battery icon.
5. If the battery lost more that 1% per minute or more than 10% in the 10 minutes, the battery should be replaced.

Test New Laptop Battery Models with a Light Meter

Some newer laptop batteries have a light meter. The light meter is on the battery and there is a button on the battery next to the light meter. This light meter can test the laptop battery’s life.

To test the laptop battery’s life on a new model with a light meter, follow these steps:

1. Press the button once to see how charged the battery is. The more the lights that show up, the more charge the battery has.

2. Hold down the button on the battery. The lights will come on and then go back off.

3. If the lights come back on then the battery is damaged to some extent. The more lights that come back on, the more the battery is damaged. So, if no lights come back on, then the battery is good. If all of the lights come back on, then the battery is bad.

4. If lights 1, 3, and 5 (both ends and the middle) flash, replace the battery as soon as possible.