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A battery is an electric power source made up of one or more electrochemical cells with connections on the outside to power electrical appliances. A battery’s positive terminal functions as the cathode and its negative terminal as the anode while it is supplying current. Electrons will come from the terminal labeled “negative” and travel to the terminal labeled “positive” via an external electric circuit. In the past, a device made of multiple cells was specifically referred to as a “battery,” but today, devices made of a single cell are also included in this definition. A brief discussion of the differences between primary and secondary batteries is provided in the following sections.
The two main categories of batteries are primary batteries and secondary. Primary batteries are intended to be used up until the voltage becomes insufficient to power a specific item, at which point they are discarded. Secondary batteries have a variety of unique structural elements and specific electrode materials that enable reconstitution (recharged). Direct current (DC) voltage can be used to recharge them after a partial or full discharge. Even though the original state is typically not fully restored, commercial batteries only lose a tiny fraction of 1 percent of their capacity per recharge cycle.
Definition of primary battery and secondary battery:
Primary batteries are intended to be utilized until their energy is depleted before being thrown away. They cannot be recharged since the majority of their chemical reactions are irreversible. The battery stops producing current and becomes useless when the reactant supply is depleted.
Secondary batteries can be recharged, which means that their chemical reactions can be reversed by passing an electric current through the cell. The initial chemical reactants are renewed in this process, allowing for multiple uses and recharge.
Difference between Primary and Secondary Batteries:
A brief representation of the differences between primary and secondary batteries is provided in the following Table.
|In primary batteries, the stored energy is inherently present in the chemical substances.
|In secondary batteries, energy is induced by applying an external source to the chemical substances.
|They are non-rechargeable.
|They are rechargeable.
|The chemical reaction that occurs in them is irreversible.
|The chemical reaction that occurs in them is reversible.
|Internal resistance is very high.
|Internal resistance is comparatively low.
|They are designed for a short period of life.
|They are designed for a long period of life.
|They have a low self-discharge rate.
|They have a high self-discharge rate comparatively.
|They have a light and simple design.
|They have a bulky and complex design.
|They have low resell value.
|They have high resell value.
|The examples of primary
cells are Leclanche cells, zinc-chlorine cells,
alkaline-manganese cells and metal-air cells
|Examples of secondary cells are lead-acid cells, nickel-cadmium cells, nickel-iron cells, nickel-zinc cells, nickel-hydrogen cells, silver-zinc cell
and high-temperature cells like lithium-chlorine cells, lithium-sulfur cells, sodium-sulfur cells, etc.
Cathode and Anode:
A cathode, or positive plate, and an anode, or negative plate, are present in every battery (or cell). These electrodes need to be spaced apart and frequently submerged in an electrolyte that allows ions to move freely between them. In order to create enough electromotive force (measured in volts) and electric current (measured in amperes) between the terminals of a battery to operate lights, machines, or other equipment, the electrode materials and the electrolyte are selected and organized. A battery of a particular size can only operate devices to a certain extent before running out of power because electrodes can only hold a finite amount of chemical energy that can be converted to electrical energy. The electrolyte solvent and air are typically kept inside and the active components of a battery are enclosed in a box that also serves as a structure for the assembly.