Battery
A battery is a hardware component that supplies power to a device, enabling that device to work without a power cord. Batteries are often capable of powering a laptop computer for several hours depending on how much power it requires. Today, many high-end devices like computer laptops and cell phones use rechargeable batteries that allow a user to recharge the battery when depleted of energy. The picture below is an example of a laptop battery with a close-up of the battery rating.
Computer batteries
There are three computer battery types used with computers. First is the backup battery, which is commonly called the CMOS battery that holds your computer's settings, such as the time and date. Without a CMOS (Complementary Metal-Oxide Semiconductor) battery, you'd have to reset the time, date, and other system settings each time the computer starts. See our CMOS page for further information on this batter.
Second, the bridge battery is only found in portable computers as a temporary backup for the main battery. A bridge battery lets you remove the main battery and replace it with a good battery without having to turn off the computer.
Third, the main battery in portable computers is an alternate source of energy for when the computer is not connected to a wall outlet.
Wireless device batteries
All wireless devices (e.g., headphones, keyboard, and mouse) require batteries. These batteries are often rechargeable batteries that are charged by connecting the device to the computer using USB (Universal Serial Bus) cable. With wireless devices that have removable batteries, open the battery compartment on the bottom of the device and remove and replace the batteries. Devices with removable batteries often use either AA batteries or AAA batteries. A device that's rechargeable is usually plugged into a USB port.
Battery technologies
There are different battery technologies that allow a battery to work. Below are some major types you're most likely to encounter.
- Li-ion (Lithium-ion)
- Li-polymer (Lithium polymer)
- NiCad (Nickel-Cadmium)
- NiMH (Nickel-Metal Hydride)
Battery backup, Battery terms, Capacity, Charge, mAH, Phone terms, Power, UPS, Voltage