Button Cell / Coin Cell Batteries

Button and coin cell batteries are used to power small, portable electronics devices like the keyless entry remote for your car, laser pointers, pocket calculators, implantable cardiac defibrillators and even artificial cardiac pacemakers[1]. 


Coin Cell Battery
Most button cell and coin cell batteries have a low self-discharge, which means they hold their charge for a long time, giving them a long shelf-life. Because they’re so consistent and reliable, these types of batteries are great for use in products that require long, continuous service. They keep us on time when used in wristwatches, and in the case of pacemakers, we trust them with our lives, with a single battery providing five to ten years of artificial heartbeat.

Coin and button cells derive their names from their shape and size – thinner variants are called coin cells because they resemble coins, while thicker ones are called button cells because, you guessed it – they look like buttons. Their size ranges from 5 to 25 millimeters in diameter and 1 to 6 millimeters in height, and they’re single cell, usually primary cell batteries, which means they are single-use and disposable. Secondary cell batteries are rechargeable, though seldom seen when it comes to coin/button cells. Most commonly, secondary button and coin cells are used in computers and handheld gaming devices to store data when the device is powered off.

There are three main types of battery chemistries used in button/coin cells: alkaline, lithium and silver oxide. While they’re physically interchangeable, certain battery chemistries are preferable depending on usage specifications. For example, high drain applications like speakers and cameras will have different energy needs than a wireless remote control. The more you know about coin and button cell specs, the better you’ll be able to maximize battery life and efficacy. We’ll take a look at some of the major characteristics of alkaline, lithium and silver oxide batteries below.

Alkaline Button/Coin Cell Batteries (1.5 Volts)

Energizer A76 Alkaline LR44 AG13When compared to lithium and silver oxide, alkaline batteries, which are denoted by the IEC prefix "LR”, provide the least capacity and stable voltage. Alkaline voltage drops gradually with use, rather than lithium and silver oxide batteries, which provide steady, stable voltage before experiencing a sharp drop-off at the ends of their lives.
[2]

Since alkalines average around half the life of lithium and silver oxide, they are cheaper, meaning they are most likely to be included with any electronics you purchase, like kids’ toys or watches. However, if you are looking to replace the batteries in such a device, it’s going to be worth your while to invest in a lithium or silver oxide battery. These may be a little more expensive, but the return on investment you’ll get will easily pay for itself. And in the case of time telling devices, or metering equipment such as the light meter on a camera, stable voltage is always preferred in order to ensure accuracy.

Silver oxide batteries, which are denoted by the IEC prefix “SR”, are also a greener alternative to alkaline, as they are recyclable.

Note: For clarification, battery voltage and mAh refer to separate energy characteristics.

mAh (milli-ampere hour) measures battery capacity. In other words – how much current a battery will discharge over a one hour period. Higher mAh ratings correspond to how long a current can be drawn, rather than how fast it can be drawn. The mAh abbreviation is also written as Ah or Ampere-hour, which equates to mAh/1000. Overall capacity is influenced by factors like temperature and speed of discharge. A 40 mAh battery can discharge 40 milliamps for one hour, 20 milliamps for two hours, and so on.

Voltage is a measurement of electrical potential, with all batteries being rated in volts DC (direct current). Voltage is determined by electrochemical reactions that occur in the battery, which vary according to battery type.

Silver Oxide (1.5 Volts) vs. Lithium (3 Volts) Button/Coin Cell Batteries Renata 377 Silver Oxide Button Cell Battery
The choice between lithium and silver oxide batteries is a matter of voltage. Lithium batteries have a nominal 3 volt output, and silver oxide batteries operate at 1.5 volts. So, you’ll want to find out what type of voltage is required for the device you’re using. The easiest way to do so is by looking at the battery being replaced, which should have all the info you need. Battery requirements can also be found in product manuals, and often on the product itself.

All coin cell lithium batteries consist of lithium manganese dioxide chemistries (Li-MnO2), which account for 80% of the lithium battery market. Li-MnO2 chemistry is denoted by the IEC prefix “CR”, which we’ll discuss more below. Because it operates at 3 volts, one Li-MnO2 can replace two alkaline or silver-oxide cells, which function at 1.5 volts. It’s worth noting that voltage can be subject to fluctuate slightly depending on the quality of the battery maker. So, the more reputable the company, the more likely the battery will be of maximal quality.

Aside from superior capacity compared to alkaline batteries, lithium and silver oxide batteries have better leakage resistance, meaning they are less subject to corrosion, which can damage and destroy your device. They are also more lightweight and heat/cold resistant, functioning better in temperature extremes.

There are a couple other aspects of silver oxide batteries worth noting. Replacing a mercury button cell, which may be found in older photography equipment, with a silver oxide battery will affect the light meter settings, requiring them to be recalibrated. Mercury batteries, which are no longer produced, operated at 1.35 volts, compared to silver oxide's 1.5 volt discharge. Also, silver oxide watch batteries may have an "SW" or "W" suffix, which some makers use to denote whether the battery is a low drain (SW) or high drain (W) device. However, the IEC simply denotes that a watch battery is compliant with its standards with a "W" suffix, which can be confusing.

You can make a reasonable determination of whether a watch or other device is high or low drain type by its features and functionality. If it's backlit, records the temperature and has a calculator, it's probably high drain. If you're not sure, the best way to be certain is to contact the manufacturer for the battery's specifications. When in doubt, go with high drain – they will last longer in both types of devices.

Battery Naming Standards

The way batteries are named can make it confusing to find what you need. Thankfully, once you know the format, the process becomes much easier.

Every battery has a standardized name. There are multiple sets of battery naming standards, but currently the most prevalent is IEC (International Electrotechnical Commission), though others such as ANSI (American National Standards Institute) may be seen.

In an ideal world, button/coin cell batteries will have their IEC classification prominently displayed.

Take a look at the battery on the right. As you can see, it’s a CR2032, which tells you that it is a single cell, round lithium battery with a diameter of 20 mm and a height of 32 mm. How did we get all that from a few letters and numbers? Let’s break it down.

The first letter, C, denotes the battery chemistry, in this case Lithium. The next letter, R, tells us the battery shape: round. Battery shapes can also be Flat (F), Square (S), and  simply Not Round (P).

Normally, three or four digit reference numbers on the batteries indicate their exact or approximate size as needed. In this case, 2032 tells us that the battery is 24mm in diameter and 3.0mm thick.

Other modifiers can be used to denote whether a battery consists of multiple cells (a numerical prefix corresponding to cell amount), whether it’s a high or low drain device and more. In silver oxide batteries, the SW suffix corresponds to use in a low drain device, while W refers to use in high drain devices.[3]

Refer to the chart below for a full list of Button/Coin cell battery types and nomenclature.

Lithium Coin Cell Battery Conversion Chart
IEC names ANSI names Typical capacity
(mAh)
Standard discharge current
(mA)
Dimensions
d. × h.
(mm)
Comments
CR927 30  9.5 × 2.7 Used extensively in blinkies. Also used in some LEGO toys.
CR1025 5033LC 30  0.1 10 × 2.5
CR1130 70 11.5 x 3.0  A rare battery, sometimes used in car security (car alarm/keyfob batteries), organizer (backup battery for PDA such as Psion etc.), and glucometer equipment. [Also some pedometers.] also k.a DL1130, BR1130, KL1130, L1130, ECR1130, KCR1130, E-CR1130, KECR1130



CR1216 5034LC 25  0.1 12.5 × 1.6 Used in some lighted watches and some LED decorator lights (electronic tea candles).
CR1220 5012LC 35–40 0.1 (CR)
0.03 (BR)
12.5 × 2.0 Used in keychain LED flashlights. Sometimes used instead of CR2032 in electronic tea lights.
CR1225 5020LC 50  0.2 12.5 × 2.5 Maximum discharge current: 1 mA. Maximum pulse discharge current: 5 mA.
CR1616 50–55 0.1 16 × 1.6 Used in automobile key remotes and in Game Boy cartridges (for powering the RAM for saved games).
CR1620 5009LC 75–78 0.1 16 × 2.0 Used in automobile key remotes and early digital watches.
CR1632 140 
120 (BR)
0.1 (CR)
0.03 (BR)
16 × 3.2 Used in automobile key remotes. (e.g., Toyota Prius 2012)
CR2012 55  0.1 20 × 1.2
CR2016 5000LC 90  0.1 (CR)
0.03 (BR)
20 × 1.6 Frequently used in digital watches. Often used in pairs instead of CR2032 for devices that require more than 3 V, like blue/white LED flashlights.
CR2020 115-125 20 × 2
CR2025 5003LC 160–165 0.2 20 × 2.5 Frequently used in digital watches and automobile remotes. Also in Fitbit Zip.
CR2032 5004LC 225 (CR)
190 (BR)
0.2 (CR)
0.03 (BR)
20 × 3.2 Maximum discharge current: 3 mA. Maximum pulse discharge current: 15 mA. Commonly used on computer Motherboards as Nonvolatile BIOS memory and Real-time clock (RTC) backup batteries. This is also the most common lithium cell. Weighs around 2.9 grams.

CR2040  ? 280  ? 20 × 4.0 3V. Used in Skytronic PRO Audible Altimeter but also flow meters and organizers (as a memory backup battery). Has become obsolete and hard to find. Other names are BR2040, DL2040, ECR2040, E-CR2040, KCR2040, KECR2040, KL2040, L2040, L24.
CR2320 110–175  23 × 2 3 V
CR2325 165–210 23 × 2.5 The most common battery size in Soviet/Russian electronic watches, calculators and remote controls.
CR2330 265 
255 (BR)
0.2 (CR)
0.03 (BR)
23 × 3.0
BR2335 165 (BR) 23 × 3.5
CR2354 560  0.2 23 × 5.4
CR2412 100  0.2 24.5 × 1.2
CR2430 5011LC 270–290 24.5 × 3.0
CR2450 5029LC 610–620  24.5 × 5.0 Portable devices requiring high current (3.0 mA) and long shelf life (up to 10 years)
CR2477 1000  0.2 24.5 × 7.7 Has the highest capacity of lithium button cell batteries.
CR3032 500–560
500 (BR)
0.1 to 0.2 (CR)
0.03 (BR)
30.0 × 3.2 Continuous discharge current take from Panasonic Catalog.
CR11108 160 11.6 × 10.8 Also called CR1/3N because it is one third the height of an alkaline N cell, and a stack of three of them will form a battery with the same dimensions as an N cell, but with 9 V terminal voltage. Such 9 V batteries in a single package do exist but are rare and only usually found in specialist applications; they can be referred to as 3CR1/3N. However 2CR1/3N, a 6 V battery consisting internally of a stack of two CR1/3N is sold by Duracell, Energizer and others. A CR1/3N was also used by photographers instead of 2 LR44 batteries, in cameras such as the Nikon EM or Nikon FE2.



Silver Oxide & Alkaline Coin Cell Battery Conversion Chart
Most
common
name
Other common names IEC names ANSI names Typical capacity
(mAh)
Dimensions
(mm)
dia. × h.
Comments
(L) = alkaline
(S) = silver-oxide
SR41 AG3/SG3/G3-A
LR41
192/384/392
6135-99-949-0402 (NSN)(S)
LR736 (L)
SR736 (S)
1135SO (S)
1134SO (S)
25–32 (L)
38–45 (S)
7.9 × 3.6
SR43 AG12/SG12
LR43
L1142
186/301/386
6135-99-547-0573 (NSN)(S)
LR1142 (L)
SR1142 (S)
1133SO (S)
1132SO (S)
80 (L)
120–125 (S)
11.6 × 4.2
SR44 AG13/SG13
LR44/LR154
6135-99-792-8475 (NSN)(alkaline)
6135-99-651-3240 (NSN)(S)
A76/S76/EPX76
157/303/357
1128MP, 208-904, A-76, A613, AG14,
AG-14, CA18, CA19, CR44, D76A,
G13A, G13-A, GDA76, GP76A, GPA7,
GPA75, GPA76, GPS76A, KA, KA76, AG76,
L1154, L1154C, L1154F, L1154G,
L1154H, LR44G, LR44GD, LR44H,
MS76H, PX76A, PX675A, RPX675,
RW82, SB-F9, V13G, 357A
LR1154 (L)
SR1154 (S)
1166A (L)
1107SO (S)
1131SOP (S)
110–150 (L)
170–200 (S)
11.6 × 5.4 Typical internal resistance: 8 ohms
SR45 AG9/SG9
LR45
194/394
6135-99-782-4675 (NSN)(S)
LR936 (L)
SR936 (S)
48 (L)
55–70 (S)
9.5 × 3.6
SR48 AG5/SG5
LR48
L750
193/309/393
LR754 (L)
SR754 (S)
1136SO (S)
1137SO (S)
52 (L)
70 (S)
7.9 × 5.4
SR54 AG10/SG10/G10-A
LR54
189/387/389/390
LR1130/SR1130
6135-99-796-0471 (NSN)(S)
LR1131 (L)
SR1131 (S)
1138SO (S) 44–68 (L)
80–86 (S)
11.6 × 3.1
SR55 AG8/SG8
LR55
191/381/391
LR1120/SR1120
LR1121 (L)
SR1121 (S)
1160SO (S) 40–42 (L)
55–67 (S)
11.6 × 2.1
365,366,S16,608 SR1116SW   28-40 11.6 × 1.65 1.55 V
SR57 AG7/SG7
LR57
195
395(low-drain)/399(high-drain)
LR927/SR927
SR927W/SR927SW/GR927
6135-99-796-0471 (NSN)(S)
LR926 (L)
SR926 (S)
1165SO (S) 46 (L)
55–67 (S)
9.5 × 2.6
SR58 AG11/SG11
LR58
162/361/362
LR721 (L)
SR721 (S)
1158SO (S) 18–25 (L)
33–36 (S)
7.9 × 2.1
SR59 AG2/SG2
LR59
196/396/397
LR726 (L)
SR726 (S)
1163SO (S) 26 (L)
30 (S)
7.9 × 2.6
SR60 AG1/SG1
LR60
164/364
LR621 (L)
SR621 (S)
1175SO (S) 13 (L)
20 (S)
6.8 × 2.1
SR63 AG0/SG0
LR63
379
LR521 (L)
SR521 (S)
10 (L)
18 (S)
5.8 × 2.1
SR64 LR64
319
LR527 (L)
SR527 (S)
12 (L)
20 (S)
5.8 × 2.7
SR65 SR616SW
321
LR65
Varta V321
6.8 × 1.65
SR66 AG4/SG4
LR66
177/376/377
SR626SW
LR626 (L)
SR626 (S)
1176SO (S) 12–18 (L)
26 (S)
6.8 × 2.6
SR67 315 SR716 (S) 21 (S) 7.9 × 1.65
SR68 SR916SW
373
LR916 (L)
SR916 (S)
  26 (S) 9.5 × 1.6
SR69 AG6/SG6
LR69
171/371
LR920/SR920
LR921 (L)
SR921 (S)
  30 (L)
55 (S)
9.5 × 2.1
SR516 SR516SW
317
LR516 (L)
SR516 (S)
  11 (S) 5.8 × 1.6
SR416 SR416SW
337
LR416 (L)
SR416 (S)
  8 (S) 4.8 × 1.6
SR731 SR731SW
24
329
LR731 (L)
SR731 (S)
  36 (S) 7.9 × 3.1
SR712 SR712SW SR712 (S)   9 (S) 7.9 × 1.3
LR932 LR932 (L)   40 (L) 9.3 × 3.2 Rarely used independently. 8 of these in series used in A23 battery.
Brand Specific Naming

Here’s where battery types and names can really get confusing. Companies often provide specific battery names other than the industry standard in order to encourage people to buy the same brand. Consumers are led to believe that there’s something unique to a certain battery. While certain brands may vary in quality, most are actually interchangeable with any other company’s model.

If you search a battery on our site, you can find other compatible models listed in the “Replacement For” section, making it easy to compare prices and features. If you’re still unsure after consulting our buyer’s guides, contact our customer service and we’ll get you on the right track.

Safety and Precautions

Important: Button and coin cells are harmful if swallowed, and are at a higher risk of being accidentally ingested by children due to their candy-like size and shape. Be sure to store, recycle and dispose of your batteries in a safe, room temperature area out of the reach of youngsters and pets.[4]

Handle old, corroded batteries with care. Battery acid is sulfuric acid, and prolonged contact with the skin can cause irritation, pain and even burns. Though they are no longer produced for environmental reasons, mercury batteries were once a popular energy source, and while it’s unlikely you would come across one today, it’s worth noting that extra care should be taken when disposing of them.

Chemistry Type

Code

Positive Electrode

Negative Electrode

Electrolyte

Nominal Voltage

End-Point Voltage

Alkaline

L

Manganese dioxide

Zinc

Alkali

1.5

1

Silver

S

Silver oxide

Zinc

Alkali

1.55

1.2

Zinc-air

P

Oxygen

Zinc

Alkali

1.4

1.2

Lithium

C

Manganese dioxide

Lithium

Organic

3

2

Lithium

B

Carbon mono fluoride

Lithium

Organic

3

2

Lithium

G

Copper oxide

Lithium

Organic

1.5

1.2

Mercury

M or N

Mercuric oxide

Zinc

Alkaline

1.35/1.40

1.1

L = Alkaline

LR = Alkaline

AG = Alkaline

SR = Silver Oxide

SG = Silver Oxide

BR or CR = Lithium

For silver oxide and lithium batteries, the end-voltage is the value at the last usable point, after which the voltage drops very rapidly. For alkalines, which lose voltage slowly, the end-point is the voltage beyond which it is deemed that devices will not work correctly, approximately 1.0 volt.

The ability to store energy in so many different capacities allows us to do things no other creature can. Though small in stature, coin and button cell batteries have played a monumental role in ushering society into its current, hyper-connected state. These batteries are kings of convenience, saving us countless hours of time and work, and allowing us to focus on the best parts of life. Buttons cells hold together the fabric of the modern world, and for all their value, coin cells might as well be the currency.


  1. https://en.wikipedia.org/wiki/List_of_battery_sizes#Button_cells_-_coin.2C_watch. Retrieved 20 October 2016.
  2. http://www.consumerreports.org/cro/batteries/buying-guide.htm. Retrieved 17 October 2016.
  3. https://en.wikipedia.org/wiki/Battery_nomenclature#History_of_the_IEC_standard. Retrieved 19 October 2016.
  4. http://www.energizer.com/about-batteries/battery-care. Retrieved 17 October 2016.