Would a Dead Laptop Battery Affect Startup?

By G.D. Palmer

Laptops rely on the battery when AC power is not available.
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Laptop computers use an AC adapter to provide power when they're plugged in, with a battery for backup power when an outlet isn't available. Most laptops start easily, even if the battery is dead, as long as they have outlet power. Some even boot without the battery in place. However, some machines always require a partially charged battery to start up correctly.

Booting from AC Only

Most laptop computers can start up with only an AC power connection, even if the battery is dead. If the computer won't start on AC power, make sure you have the correct power cable and check that the cord is undamaged. Try a different outlet in case the first one doesn't work. Remove and reseat the battery in case your computer has a bad connection. For models that require a working battery to boot, consider leaving the laptop plugged in for a short period to give the battery enough charge to start the computer.

Damaged Battery

A damaged battery can interfere with the computer's startup process. Try removing the battery, then starting the computer without it. Some laptops won't start without a battery physically seated in the laptop, but others will boot. If this doesn't work, try swapping your battery with another one made for the same model of laptop. If the new one works, you may need to replace your laptop battery. Many laptops have a light that indicates whether the battery is charging. If your computer is plugged in and the light stays off, you may need to replace the battery.

Booting with No Battery

Some laptop computers can boot with an AC connection and no battery installed. Others require the physical presence of a battery, even if that battery is dead. If your computer does start up with no battery, it may not remember the correct time and date. If your computer needs a battery to work, it may not start if the battery is completely dead. Leave the laptop plugged in for a few minutes to give the battery a tiny charge. This may allow you to boot your laptop.


All laptop batteries lose their ability to hold a charge over time and must be replaced. Proper storage and power management techniques can keep yours in good condition longer. Avoid leaving the notebook fully charged at all times, as this reduces the battery's ability to hold power. Keep batteries in cool locations and don't let them overheat. Dim screens and turn off Wi-Fi and Bluetooth connections when not in use. If you need to store your battery for a longer period of time, remove it from the computer at about a 50 percent charge. Storing the battery fully charged or fully discharged can reduce its ability to hold power later.