Disposable batteries are single-use power sources that are replaced after they run out of charge. Also called primary cells, they're commonly known by their size (such as AA, AAA, or 123) which is defined according to ANSI/IEC standards. These batteries are typically used in flashlights, remote controls, smoke detectors, occupancy sensors, light-duty power screwdrivers, and other small devices. They're also used to supply backup power for devices that are primarily powered by electricity. Disposable batteries with alkaline or carbon zinc chemistry can be discarded with everyday trash while lithium batteries should be recycled.

Batteries and battery chargers provide power and portability to electrical devices and equipment. Original equipment manufacturer (OEM) batteries can replace manufacturer-specific batteries in compatible devices such as cordless tools, lanterns, and two-way radios. Disposable, household batteries are commonly used in low-drain devices such as flashlights, remote controls, clocks, and smoke detectors. High-performance batteries provide increased capacity to handle spikes in power demand from high-drain devices such as digital cameras, thermal imagers, digital audio, drones, video game controllers, GPS equipment, and keyless entry systems. Rechargeable batteries can be used repeatedly without the need for constant replacement. Battery chargers replenish the power of depleted rechargeable batteries.