Hello, this is Fujiwara from Cyack Lab.
In this article, I’d like to introduce some key points for engineers to consider when selecting a coin cell battery (CR2032).
Even though we simply say “coin cell battery,” there are actually many different types available from various manufacturers.
With so many options out there, I hope this article will help you choose the coin cell battery that best fits your product.
By reading through this article, you’ll also gain a deeper understanding of coin cell batteries, so I encourage you to read it to the end and expand your knowledge.
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What is a CR2032?
The term “CR2032” refers to a standardized designation for a type of coin cell battery.
This naming convention provides information such as the battery’s size and the material used for the positive electrode.
The first letter, “C,” indicates that manganese dioxide is used as the cathode material.
Other examples include “B”, which stands for graphite fluoride, among others.
The second letter, “R,” signifies that the battery is round in shape.
The first two digits in the number represent the diameter in millimeters, and the last two digits represent the height (thickness) in tenths of a millimeter.
In the case of CR2032, the battery has a diameter of 20 mm and a height of 3.2 mm.
You might think that if all manufacturers follow the same standard, there wouldn’t be much difference between CR2032 batteries—but in reality, a wide variety of CR2032 types are available from different manufacturers.
In this article, I will introduce four major types of CR2032 batteries.
I hope this helps you select the most suitable coin cell battery for your product.
CR2032 Battery Selection Guide
When it comes to choosing a CR2032 battery, the selection process can generally be divided into four main categories:
Choosing by manufacturer, by capacity, by discharge characteristics, and by temperature resistance.
Below, I’ve outlined the key features and points to consider for each of these selection methods.
Please use this as a reference when selecting the most suitable battery for your needs.
Choosing by Manufacturer
When selecting a manufacturer, the first thing to consider is which country the manufacturer is based in.
Depending on the country, some manufacturers may offer higher quality products, while others may focus on lower cost.
If you’re looking for Japanese manufacturers, the main ones include Maxell, Panasonic, Sony, FDK, and Murata Manufacturing.
In general, choosing a manufacturer from a country closer to you may result in lower shipping costs and potentially more affordable prices.
However, it is recommended to also consider safety and product quality in order to choose the most suitable manufacturer.
Choosing by Capacity
The standard CR2032 battery has a nominal capacity of 220mAh, but high-capacity versions are also available.
For example, Maxell offers a model called the CR2032H, which has a nominal capacity of 240mAh.
This is a great option for those who want to choose a battery with as much capacity as possible.
Choosing by Discharge Characteristics
In a typical CR2032 battery, drawing a high current can lead to significant voltage drop, which in the worst case may cause the device to stop functioning.
As IoT continues to advance, some devices now require temporary bursts of high output, such as for sensing or wireless transmission.
To meet these needs, many manufacturers have released high-drain (high-output) versions of coin cell batteries.
For example, Murata Manufacturing offers a high-drain model called the CR2032R, which can deliver approximately twice the maximum discharge current compared to standard models.
Devices that struggle to operate with standard coin cells may function properly when using a high-drain type.
For products that require temporary high output, a high-drain CR2032 is strongly recommended.
Choosing by Temperature Resistance
As IoT technology continues to advance, more devices are being developed for use in harsh environments. In response to this trend, manufacturers are now offering coin cell batteries that can operate under high-temperature conditions.
For example, Murata Manufacturing offers a temperature resistant model called the CR2032W.
While the standard CR2032 has an operating temperature range of -30°C to 70°C(-22°F to 158°F), the heat-resistant version extends that range to -40°C to 125°C(-40°F to 257°F).
If your product cannot operate due to the limited temperature range of a standard coin cell, using a heat-resistant type may enable operation even in extreme environments.
Recommendations for the Standard Type
I’ve introduced various types of coin cell batteries, but the standard type I personally recommend is the one made by Panasonic.
The reason I recommend Panasonic is that it offers the longest battery life among standard coin cells.
While actual performance may vary depending on the usage environment and conditions, Panasonic coin cells consistently show the best discharge characteristics in testing.
When using coin cells to power a device, battery life is a critical factor.
In some cases, battery life can be more important than the core features of the product itself. It’s not uncommon for customers to choose the product with the longer operating time.
You definitely want to avoid a situation where choosing a cheaper battery to reduce costs results in shorter battery life—and ultimately leads your customers to choose a competitor’s product instead.
[Bonus Topic] Near-Perpetual Operation!? What Is a Dummy Coin Cell?
Up to this point, we’ve introduced various types of CR2032 coin cells. However, there is also a unique type of coin cell offered by Cyack Lab called the DB-R2032 Dummy Coin Cell.
Unlike regular coin cells, a dummy coin cell is designed to allow power to be supplied from an external source.
It retains the shape of a CR2032, so by connecting the dummy coin cell to an AC adapter or similar power source, you can power devices originally designed for coin cell operation using external electricity.
Since power can be supplied from an AC adapter or other external sources, this allows the device to operate almost perpetually, without the need to replace the battery.
The dummy coin battery is recommended for testing and development of products powered by coin cells.
It is also ideal for those who want to reduce the cost of replacing coin batteries or extend the lifespan of CMOS batteries by replacing them with cylindrical cells.
Here is more information about the dummy coin battery “DB-R2032.”
Summary
In this article, we introduced key points for engineers to consider when selecting a coin cell battery.
We hope this guide helps you choose the most suitable coin battery for your product.