Demystifying Coin Cell Batteries: CR2025 vs CR2032

Understanding Coin Cell Battery Basics

As the name indicates, coin-cell batteries (sometimes called button cells or micro batteries) are coin-shaped single-cell batteries.

We can trace their origins back to the late 1930s and early 1940s. Most historians credit Samuel Ruben as their inventor. He primarily created them for portable military equipment. 

Modern coin cell batteries use lithium or zinc anodes paired with silver oxide, carbon monofluoride, copper oxide, manganese dioxide, or dioxygen cathodes.

Variations with manganese dioxide cathodes (positive electrodes) are typically named after their anodes (negative electrodes).

We denote Silver, iron sulfide, and mercury coin cell batteries according to their cathode (positive electrode).

This is because they also either use a zinc or lithium anode. Here are the most current common coin cell batteries and their chemical compositions:

Coin cell batteries come in a wide variety of sizes and chemical compositions. However, because some may appear similar, as is the case with CR2025 and CR2032, we need another way to tell them apart. 

Coin Cell Battery Illustration

Decoding the Coin Cell Code

The International Electrotechnical Commission (IEC) introduced the 60086-3 standard to help categorize and identify watch batteries.

It uses an alphanumeric coding system where each character (from left to right) represents one of the battery’s characteristics.

The first character denotes the chemical makeup or type of battery. You may have noticed a letter parenthesized next to the battery name in the previous section. It’s a reference to the first part of the IEC code. 

For instance, L is assigned to alkaline batteries, while C represents Lithium batteries such as CR2025 and CR2032.

The second character indicates the shape of the battery. For instance, R = round/cylindrical. 

The last few characters of the code represent package size.

The first number denotes the nominal diameter and can be a single or two-digit code.

The second number follows the same rule as the first and denotes the height or thickness. 

There are exceptions, such as the LR44. It is an alkaline battery with a nominal diameter of 11.6 mm and a height of 5.4 mm.

LR 44 compared with CR 2032

By using these codes, we can already identify the similarities and differences between CR2025 and CR2032 batteries.             

Please note: The above naming conventions apply to non-rechargeable coin batteries.

Rechargeable batteries are given additional prefixes, such as LiR, for rechargeable CR batteries.    

CR2025 vs CR2032: A Detailed Look

What Are Key Similarities and Considerations?

• Voltage and Chemistry

Both the CR2025 and CR2032 are non-rechargeable lithium-ion batteries. They have the same diameter – (20.0 mm). Additionally, they both have a similar temperature operating and aging range (-30 to 60 °C). 

• Shelf Life

As is the case with most Lithium coin cell batteries, they have a 1% self-discharging rate. This means they lose 1% of their charge for every year that they sit on the shelf. Thus, they both have near identical average shelf lives (a decade). That’s if you store them under the same conditions. 

• Applications

Because of their many similarities, the CR2025 and CR2032 have overlapping use cases. You can find them in:

• Wristwatches
• Pocket calculators
• Hearing aids
• Fitness devices
• Temp sensor
• Laser pens
• Medical devices
• Real-time clock module boards
• Garage door openers
• LED lights

Coin Cell Battery in LED Light Circuit

In some instances, you can use these batteries interchangeably without trouble. However, some devices may not allow it. But why is this when both these battery types seem so similar? 

Key Differences and Choosing the Right Battery

Thickness

The most significant difference between the CR2025 and CR2032 batteries is their thickness/height. The CR2025 has a height of 2.5mm, whereas the CR2032 has a height of 32mm. Most devices will accommodate both batteries, but the CR2032 will sit more snugly in the battery compartment.

Capacity

The size difference isn’t just mechanical or aesthetic. It’s proportional to the amount of reserve capacity each battery can store. Because the CR2032 is thicker, it has a better capacity than the CR2025. The CR2032 has a storage reverse capacity of 235 milliampere-hours (mAh) compared to the CR2025’s 170 mAh capacity. 

This means that your CR2025 will discharge faster than the CR2032 battery under load. The CR2025 will last for about 2-3 months under heavy load. Comparatively, the CR2032 has a battery life of 3-4 months.

CR2032 Lithium Cell Coin Rendering 

A higher mAh capacity affects the shelf-life too. Hence, the CR2032 has a slightly longer average shelf-life than the CR2025. However, it’s only around a few weeks or a month longer. 

Interchangeability   

Different electronics have different power source requirements and thus, drain batteries differently.

How much a device drains (and how long a battery lasts) depends on the active device and the dynamic loads applied to the lithium cells in the battery.

Generally, lithium batteries with high initial discharge rates tend to have extremely low overall discharge rates. Hence, these batteries last longer than alkaline batteries.

However, because CR2025 and CR2032 have different sizes and capacities, they aren’t always interchangeable. 

How to Choose the Right Battery?

Consider device Requirements

Most portable device manufacturers prefer using CR2032 coin batteries because of their larger capacities.

For instance, most (if not all) PC motherboards use CR2032 batteries. While many of these devices can accommodate CR2025 batteries, they may fit too loosely. 

Additionally, if you use a CR2025 battery in place of a CR2032, you must consider that it’s likely to drain faster. Thus, you’d have to replace it sooner than you would the recommended battery type.

High Drain vs Low Drain Devices

If you are powering a simple device like a toy or a remote, then you’d want to use the CR2025.

In comparison, the CR2032 coin cell battery might be the preferred choice for active devices such as medical, hearing aids, pacemakers, digital watches, etc. 

These devices need a long shelf life, quality material, additional charge, and larger capacity.

Checking the appliance manual for the electrical devices will also tell you what typical capacity you need and the lithium battery to use.

Additional Considerations

Closeup of Button Cell Battery

If you find that you have no choice but to substitute the CR2032 with a CR2025 in a larger compartment, do the following:

Take a piece of aluminum foil (you can also use another conductor), then push it into the space above the battery. Make sure you place the folded piece on the positive (+) side of the battery.

A few smaller devices (such as watches) still use CR2025 batteries. In these cases, it may be possible to fit a CR2032 battery type and benefit from its superior charge.

However, some compartments are strictly meant for thinner battery types and thus can’t fit the CR2032. Unfortunately, there is no way around this.

Beyond CR2025 and CR2032

Lithium batteries provide long-lasting, reliable power in comparison to alkaline batteries. However, lithium batteries tend to cost more than alkaline batteries.

Nevertheless, in most cases, it’s likely you’d still prefer to stick to lithium coin cell batteries. 

CR2025 and CR2032 batteries aren’t the only lithium batteries with a 20.0mm diameter. You can also find:

• CR2012: 1.2 mm thickness (55 mAh)
• CR2016: 1.6 mm thickness (90 mAh)
• CR2020: 2.0 mm thickness (115-125 mAh)
• CR2040: 4.0 mm thickness (280 mAh)
• CR2050: 5.0 mm thickness (350 mAh)

Types of battery size comparison

The CR2032 is still the most commonly used lithium cell despite being thicker than a CR2012 or having less capacity than the CR2050.

Both the CR2025 and C2032 provide a balance between size and capacity, and that’s why they’re still so popular.

Despite their high capacity, batteries such as the CR2040 and CR2050 are less common. In fact, the CR4040 is essentially obsolete.   

All these batteries consist of the same material, have the same cutoff voltage (3V) and share the same diameters.

Thus, you can use them interchangeably (if device compartment space allows).

In fact, you can stack two CR2016 batteries and use them in place of a CR2032. This is especially ideal for applications that require electrical charges higher than 3V. 

Two CR2016 batteries have a combined thickness of 3.2 mm and a combined cutoff voltage of 6V.  

Lithium coin batteries can also be found in diameters of:

• 9.5mm (CR927)
• 10mm (CR1025)
• 11.5mm (CR1130)
• 12.5mm (CR1216, CR1225)
• 16mm (CR1616, CR1620, CR1632)
• 23mm (CR2320, CR2330, CR2354)
• 24.5mm (CR2412, CR2430, CR2450, CR2477)
• 30mm (CR3032)

All have their specific use cases, voltage cutoffs, capacities and limitations and thus cannot be used in place of CR20 batteries.

Button Coin Batteries Vector

Conclusion

In conclusion, both the battery options have similarities and differences. Both provide long-lasting, reliable power and are an alternative to traditional batteries.

The only difference between CR2025 vs. CR2032 you need to account for when choosing one of these two batteries include:

• Capacity
• Thickness
• Usage

Trying to wire LEDs and CR2032 batteries to make it work? Contact us!