We had multiple customers this week calling in to get help choosing the right coin cell batteries for their application. This blog kind of helps to bring some clarity into the whole process of how to choose a battery and what are important factors while considering one of these for your projects.
First off there are different names by which these batteries are called Coin Cells, Button Cells, Watch Cells.
What kind of applications does button cell show up often ?
Button cells find their way into portable electronics that have low power requirements and a need for portability becomes prime need. The coin cell batteries are often found usage in small portable electronics like watches, calculators, remotes of cars ..etc.
What is the coin cell made off ?
Coin cells usually have a insulated top and a stainless steel bottom side with the top side being the negative terminal and the bottom being the positive. The batteries generally also come marked with a + symbol at the bottom side.
Materials in the Button cells.
If the Button Cells are :
Common Anode generally use : Zinc , Lithium
Common Cathode generally use : Manganese dioxide, Silver oxide, Carbon monofluoride, Cupric oxide or Oxygen
Does Batteries have a Nomenclature and how demystify it ?
Most of the commonly found button cells out there conform to what is known as the IEC (International Standard Commission).
For example lets consider CR2032 . The way to read this is as below
C – Indicates Lithium
R – Round Type
20 – Is the diameter which is 20 mm
3 – indicates nominal voltage which is 3V
2 – indicated End poin voltage which is 2V.
A table that helps in most of the cases is below :
| Letter code | Common name | Positive electrode | Electrolyte | Negative electrode | Nominal voltage (V) | End-point voltage (V) |
|---|---|---|---|---|---|---|
| L | Alkaline | Manganese dioxide | Alkali | Zinc | 1.5 | 1.0 |
| S | Silver | Silver oxide | Alkali | Zinc | 1.55 | 1.2 |
| P | Zinc-air | Oxygen | Alkali | Zinc | 1.4 | 1.2 |
| C | Lithium | Manganese dioxide | Organic | Lithium | 3 | 2.0 |
| B | Carbon monofluoride | Organic | Lithium | 3 | 2.0 | |
| G | Copper oxide | Organic | Lithium | 1.5 | 1.2 | |
| Z | Nickel oxyhydroxide | Manganese dioxide, nickel oxyhydroxide | Alkali | Zinc | 1.5 | ? |
| M, N (withdrawn) | Mercury | Mercuric oxide | Alkali | Zinc | 1.35/1.40 | 1.1 |
I hope this helps in understanding a bit about the overall coin cell batteries and some nomenclature that aids in buying one of these for your next project.
If you need further help and support to select one of these feel free to always reach us out through our webstore and as always we would be happy to support !
