Other Coin Cell Batteries

CR2025, CR2016, CR1220,

Brief about CR2032 Batteries

Coin cell batteries like CR2032 are generally used for small portable electronics devices such as wrist watches, pocket calculators, automobile key less entry transmitter and hearing aids. Typically they are of compact size, 5-25mm in diameter and 1-6mm in height. The name defines the size of the battery like for CR2032, the first two digits stands for diameter and second for height or thickness in tenths of mm. So, according to this 20mm is the diameter of CR2032 and 3.2mm is the thickness.

Lithium button or coin cell batteries are a bit costly than alkaline, but last longer, weigh less and have a wide operating temperature range.

For the Pulse Discharge and Continuous Discharge Characteristics check the attached CR2032 battery datasheet at the end of the page.

How to calculate the run time of your CR2032 battery

The CR2032 is a commonly used battery for portable electronics applications. The life time of the battery depends on the many parameters like operating temperature, discharge current, dynamic loads etc. But for the sake of simplicity let us assume that we power a normal load which consumes a constant current of 20mA at 20°C. Then in that case the mAh capacity of our battery is 240mAh. This means that if we draw 240mA, then our battery will last for 1 hour and similarly if we draw 120mA then the battery will last for 2 hours. So for our application which consumes only 20mA the battery should last for (240/20) 12 hours. However this figure will not be accurate due to the varying current and operating temperature of the system. The datasheet also provides a neat graph to understand the same

Internal Resistance Characteristics

Another important parameter to consider while deciding your battery is the internal resistance of the battery. Sadly every battery will have some internal resistance associated with it which will prevent you from drawing maximum current from the battery. The lower the IR (Internal Resistance) the more current you will be able to draw from it and higher the efficiency of the battery will be, the IR of a battery will increase as it ages or due to its operating environment.

When, performing Pulse Test at 25℃, continuous background drain at 15k ohms is 0.193mA @ 2.9V. And, pulse drain in every 2 seconds *12 times/delay at 400 ohms is 6.8mA @ 2.7V.

How to Use CR2032 Battery?

There are many application of coin cell batteries, the below circuit shows you that how to connect a CR2032 coin cell battery with a simple LED circuit. CR2032 provide a nominal voltage of 3.0V, to power up a simple LED we need a minimum voltage of 2.2V so we have used the resistance for protection or current limiting.

Applications

• Key fob for cars.
• Wireless doorbell for house.
• CMOS battery in computers.
• Glucometers
• Digital thermometers
• Digital altimeter
• Cyclocomputers
• Heart rate monitors

2D-model