18650 li ion battery

This article lists the sizes, shapes, and general characteristics of some common primary and secondary battery types in household and light industrial use.

Historically the term "battery" referred to a collection of electrochemical cells connected in series, however in modern times the term has come to refer to any collection of cells (or single cell) packaged in a container with external connections provided to power electrical devices, leading to the variety of standardized form factors available today.

The long history of disposable dry cells means that many different manufacturer-specific and national standards were used to designate sizes, long before international standards were agreed upon. Technical standards for battery sizes and types are published by standards organizations such as International Electrotechnical Commission (IEC) and American National Standards Institute (ANSI). Many popular sizes are still referred to by old standard or manufacturer designations, and some non-systematic designations have been included in current international standards due to wide use.

The complete nomenclature for a battery specifies size, chemistry, terminal arrangement, and special characteristics. The same physically interchangeable cell size or battery size may have widely different characteristics; physical interchangeability is not the sole factor in substituting a battery.

The current IEC standards for portable primary (non-rechargeable) batteries bear the 60086 number. The relevant US standards are the ANSI C18 series, which are developed by a committee of the US National Electrical Manufacturers Association (NEMA).

Both standards have several parts that cover general principles, physical specifications, and safety. Designations by IEC and ANSI standards do not entirely agree, though harmonization is in progress. Also, manufacturers have their systems for identifying cell types, so cross-reference tables are useful to identify equivalent types from different manufacturers.

Lead-acid automotive starting, lighting and ignition batteries have been standardized according to IEC standard 60095 and in North America by standards published by BCI.

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