Lithium batteries are primary batteries that have lithium metal or lithium compounds as an anode. Depending on the design and chemical compounds used, lithium cells can produce voltages from 1.5 V to about 3 V, twice the voltage of an ordinary zinc-carbon battery or alkaline cell. Lithium batteries are used in many portable consumer electronic devices, and are widely used in industry.

Lithium batteries find application in many long-life, critical devices, such as artificial pacemakers and other implantable electronic medical devices. These devices use specialized lithium-iodide batteries designed to last 15 or more years. But for other, less critical, applications such as in toys, the lithium battery may actually outlast the toy. In such cases, an expensive lithium battery is not cost-efficient.

Lithium batteries can be used in place of ordinary alkaline cells in many devices, such as clocks and cameras. Although they are more costly, lithium cells will provide much longer life, thereby minimizing battery replacement. However, attention must be given to the higher voltage developed by the lithium cells before using them as a drop-in replacement in devices that normally use ordinary cells.

Small lithium batteries are very commonly used in small, portable electronic devices, such as [[personal digital assistant|PDAs]], watches, thermometers, and calculators, as backup batteries in computers and communication equipment, and in remote car locks. They are available in many shapes and sizes, with a common variety being the 3 volt "coin" type manganese variety, typically 20 mm in diameter and 1.6–4 mm thick. The heavy electrical demands of many of these devices make lithium batteries a particularly attractive option. In particular, lithium batteries can easily support the brief, heavy current demands of devices such as digital cameras, and they maintain a higher voltage for a longer period than alkaline cells.