Type CR2032 watch battery (lithium anode, 3 V, 20.0 mm × 3.2 mm)

A watch battery or button cell is a small form-factor battery designed for use in wrist watches, pocket calculators, hearing aids, and similar compact portable electronics products. Watch batteries are usually a single cell with nominal voltages between 1.5 and 3 V. Common anode materials are zinc or lithium, common cathode materials are manganese dioxide, silver oxide, carbon monofluoride or copper oxide. The cylindrical surface of these types of batteries is part of the positive (+) terminal. Image File history File linksMetadata Battery-lithium-cr2032. ... Image File history File linksMetadata Battery-lithium-cr2032. ... This does not cite its references or sources. ... Diagram of a zinc anode in a Daniells cell. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Appearance bluish pale gray Atomic mass 65. ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/grey Atomic mass 6. ... Manganese(IV) oxide (MnO2) is a chemical compound also known as manganese dioxide or manganese oxide. ... This page is a candidate for speedy deletion, because: it is patent nonsense. ... Copper forms two oxides, copper(I) oxide (cuprous oxide, Cu2O) a red powder and copper(II) oxide (cupric oxide, CuO) a black powder. ...

Type designation

International standard IEC 60083-3 defines an alphanumeric coding system for watch batteries. Standards are produced by many organizations, some for internal usage only, others for use by a groups of people, groups of companies, or a subsection of an industry. ...

Electrochemical system

The first letter identifies the electrochemical system used in the battery, which also implies a nominal voltage:

The "C"-type 3-V lithium cells are today the most commonly used type in quartz watches, calculators, small PDA devices, and computer motherboard clocks. A quartz clock. ... For other uses, see Calculator (disambiguation). ... PDA may stand for: Personal digital assistant, a digital device which can include the functionality of a computer, a cellphone, a music player and a camera Pitch detection algorithm, a mathematical method of finding the pitch of a signal Public display of affection, an area of study within social psychology...

Package size

Its package's size is identified by a three-to-four digit code, preceded by the letter "R" to indicate a round cell. The first 1–2 digits indicate the outer diameter of the battery (downwards-rounded millimeters), and the last two digits indicate the overall height (downwards-rounded 0.1 millimeters). Examples:

• CR2032: 20.0 mm diameter, 3.2 mm height
• SR516: 5.8 mm diameter, 1.6 mm height

ISO/IEC 83-3 lists the following diameter codes:

4 = (4.8⁺⁰_−0.15) mm

5 = (5.8⁺⁰_−0.15) mm

6 = (6.8⁺⁰_−0.15) mm

7 = (7.9⁺⁰_−0.15) mm

9 = (9.5⁺⁰_−0.15) mm

11 = (11.6⁺⁰_−0.20) mm

12 = (12.5⁺⁰_−0.25) mm

16 = (16⁺⁰_−0.25) mm

20 = (20⁺⁰_−0.25) mm

23 = (23⁺⁰_−0.50) mm

24 = (24.5⁺⁰_−0.50) mm

The following height codes are used with 16–24 mm diameter batteries:

12 = (1.20⁺⁰_−0.20) mm

16 = (1.60⁺⁰_−0.20) mm

20 = (2.00⁺⁰_−0.25) mm

25 = (2.50⁺⁰_−0.50) mm

30 = (3.00⁺⁰_−0.50) mm

32 = (3.20⁺⁰_−0.50) mm

Final letters

After the package code, the following additional letters may optionally appear in the type designation to indicate the electrolyte used:

• S: Sodium hydroxide electrolyte
• P: Potassium hydroxide electrolyte
• no letter: organic electrolyte

An appended letter "W" states that this battery complies with all the requirements of the IEC 86-3 standard. Sodium hydroxide (NaOH), also known as lye or caustic soda, is a caustic metallic base. ... The chemical compound potassium hydroxide, (KOH) sometimes known as caustic potash, potassa, potash lye, and potassium hydrate, is a metallic base. ...

Other package markings

Apart from the type code described in the preceding section, watch batteries should also be marked with

• the name or trademark of the manufacturer or supplier;
• the polarity (+);
• the date of manufacturing.

The manufacturing date can be abbreviated to the last digit of the year, followed a digit or letter indicating the month, where O, Y, and Z are used for October, November and December, respectively (e.g., 01 = January 1990 or January 2000, 9Y = November 1999).

Common applications

• Quartz wrist watches, both digital and analog.
• Calculators
• Hearing aids
• Some remote controls, especially for keyless entry
• Backup power for personal computer real time clocks and BIOS configuration data.
• Small PDA devices
• Various electronic toys (tamagotchi)
• Laser pointers
• Small LED flashlights are commonly powered by three button (silver-oxide) cells in series.
• Battery-operated children's books

A wrist watch A watch is a small portable timepiece or clock that displays the time and sometimes the day, date, month and year. ... For other uses, see Calculator (disambiguation). ... A hearing aid is a device used to help the hard-of-hearing hear sounds better. ... A television remote control A DVDplayer remote control A remote control is an electronic device used for the remote operation of a machine. ... Entry remote for a Chrysler vehicle A remote keyless system is a system designed to remotely lock, or unlock, access to premises or automobiles. ... A real-time clock (RTC) is a computer clock (most often in the form of an integrated circuit chip) that keeps track of the current time even when the computer is turned off. ... Nonvolatile BIOS memory refers to the memory on a personal computer motherboard containing BIOS settings and sometimes the code used to initialize the computer and load the operating system. ... palmOne Tungsten T5 (CDAs) are handheld devices that were originally designed as personal organizers, but became much more versatile over the years. ... Tamagotchi Plus, with a Marutchi character on-screen. ... The current version of the article or section reads like a magazine article instead of the formal tones expected of an encyclopedia. ... External links LEd Category: TeX ... Green Flashlight Note that Flashlight is the NATO designation for the Yakovlev Yak-25 Soviet military jet. ...

Rechargeable variants

Regular watch batteries are not rechargeable. Rechargeable button cells are commercially available, but are not commonly used due to their inferior capacity. Rechargeable batteries are batteries that can be restored to full charge by the application of electrical energy. ...

Other chemical compositions

• Mercury cells are now banned from sale in many countries.
• Alkali cells are sometimes found in low-end markets, but do only provide a fraction of the capacity of silver oxide or lithium based cells.
• Zinc-air cells utilize air in the chemical reaction (it is required to remove a plastic foil layer before usage).

A Mercury battery (also called mercuric oxide battery, or mercury cell) is a non-rechargeable electrochemical battery, a primary cell. ... 2 Duracell-Brand AAA Alkaline batteries Alkaline batteries are a type of power cell dependent upon the reaction between zinc and manganese dioxide (Zn/MnO2). ... Zinc-air batteries, also called zinc-air fuel cells are a non-rechargeable electro-chemical battery powered by the oxidation of zinc with oxygen from the air. ...

References

• IEC 60086-3: Primary batteries — Part 3: Watch batteries. International Electrotechnical Commission, Geneva, 1995. (also: BS EN 60086-3:1996)