They are available in a variety of sizes, from very small button cells for hearing aids to the large batteries used in film cameras.

It is defined as the maximum current that can be applied to charge the battery. This is practically a maximum of 1A/2A that can be applied if a battery protection circuit is built-in but still 500 mA is the best range for a battery charge.

These types of batteries are composed of cells in which lithium ions move from the negative electrode through the electrolyte to the positive electrode during discharge and back when it’s charging. Lithium-ion batteries are used in heavy electrical current usage devices such as remote car fobs.

Battery life can be extended by storing the batteries at a low temperature, as in a refrigerator or freezer, which slows the side reactions. Such storage can extend the life of alkaline batteries by about 5%; rechargeable batteries can hold their charge much longer, depending upon type.

Batteries can only provide a DC power supply that is generated from a chemical reaction that takes place within the battery. Batteries also only ever feature positive and negative terminals where the current will only ever flow in the same direction between the two terminals.

In the 2000s, developments include batteries with embedded electronics such as USBCELL, which allows charging an AA battery through a USB connector, nanoball batteries that allow for a discharge rate about 100x greater than current batteries, and smart battery packs with state-of-charge monitors and battery protection circuits that prevent damage on over-discharge. Low self-discharge (LSD) allows secondary cells to be charged prior to shipping.

Benjamin Franklin first used the term "battery" in 1749 when he was doing experiments with electricity using a set of linked Leyden jar capacitors. [4] Franklin grouped a number of the jars into what he described as a "battery", using the military term for weapons functioning together.

To balance the flow of electrons, charged ions (atoms or molecules with an electric charge) also flow through an electrolyte solution that is in contact with both electrodes. Different electrodes and electrolytes produce different chemical reactions that affect how the battery works, how much energy it can store, and its voltage.

The C-rate is a measure of the rate at which a battery is being charged or discharged. It is defined as the current through the battery divided by the theoretical current draw under which the battery would deliver its nominal rated capacity in one hour.[51] It has the units h−1. Because of internal resistance loss and the chemical processes inside the cells, a battery rarely delivers nameplate rated capacity in only one hour. Typically, maximum capacity is found at a low C-rate, and charging or discharging at a higher C-rate reduces the usable life and capacity of a battery.

Zinc-air: Several technologies and configurations employ metallic zinc as the battery anode. Zinc-air batteries generate electricity when zinc is oxidized with oxygen from the air. They have a higher energy density акумулатори цена than lithium-ion batteries, meaning that they can store more energy in a smaller space. The small batteries used in hearing aids today are typically zinc-air batteries, but they could also be used at larger scales for industrial applications or grid-scale energy storage.

Batteries that successfully traverse the esophagus are unlikely to lodge elsewhere. The likelihood that a disk battery will lodge in the esophagus is a function of the patient's age and battery size. Older children do not have problems with batteries smaller than 21–23 mm. Liquefaction necrosis may occur because sodium hydroxide is generated by the current produced by the battery (usually at the anode). Perforation has occurred as rapidly as seis hours after ingestion.[77]

Charging voltage refers to the maximum voltage that must be applied to the battery in order to charge the battery efficiently. Basically, 4.2 V considers the best charging voltage.

With regards to anodes, a number of chemistry changes have the potential to improve energy density (watt-hour per kilogram, or Wh/kg). For example, silicon can be used to replace all or some of the graphite in the anode in order to make it lighter and thus increase the energy density.

Sony has developed a biological battery that generates electricity from sugar in a way that is similar to the processes observed in living organisms. The battery generates electricity through the use of enzymes that break down carbohydrates.[37]