An Extensive Guide On Coin Cell Battery: Working, Features & Applications

Today, the world is moving towards smaller devices and gadgets that are convenient to use on the go. These devices include personal gadgets, games, electronic toys, medical instruments, and batteries. 

If you think batteries are already one of the smallest devices embedded in an electronic gadget, you will be amazed to know that even smaller batteries, such as the size of a coin, are prevalent for usage. Yes, we are talking about coin cell batteries!

Coin cell batteries are sometimes also referred to as penny cell batteries. Many people misinterpret them as button cell batteries, but there is a slight difference. Coin batteries are less thick and have a greater diameter than button cell batteries.

Mostly, coin batteries have a low self-discharge rate. It means they hold a charge for a longer span, which facilitates a long shelf life. As coin batteries are consistent and reliable, these are ideal for use in portable products that need a longer service.

If you want to know more about a coin cell battery, stay with us till the end of the blog!

What is A Coin Cell Battery?

Also called lithium-metal batteries, coin cell batteries are basic batteries that have metallic lithium as an anode. These batteries have the shape and size of a coin or penny. 

Notably, these are one of the smartest battery cells in the world of batteries. Coin batteries are not very expensive and are ideal for powering small devices, LED projects, etc.

Besides, there are different technologies and chemistries concerning coin cells. Some cells are lithium, while others are alkaline. The nominal voltage of alkaline coin batteries is 1.5V, whereas that of lithium coin batteries is 3V.

Working Mechanism of a Coin Cell Battery

Now, let us understand how coin batteries work!

A coin battery works similarly to AA and AAA batteries. Their circular body consists of two electrodes (cathode and anode) of complementary metals. Usually, stainless steel forms the bottom body and the positive terminal of the battery. 

The metallic top insulated from the positive terminal forms the negative terminal. Both terminals are separated by an electrolyte that acts as a separator and also controls the movement of ions that generates the electric power.

When the battery is discharged or used, the cathode receives positively charged lithium ions which make it positively charged. Now, the positively charged cathode attracts electrons (negatively charged) that flow via the circuit of devices and constantly power it as long as it is connected. The reverse of this process happens when the cell battery is being charged.

Notably, for the prevention of short circuits and leakage, the manufacturers of coin cell batteries use chemically stable materials.

How to Understand Coin Cell Naming (Formats & Sizes)?

Coin lithium cell batteries come in several sizes. Each cell has a specific coded name that describes its size and chemistry. The International Standard IEC has specified an alphanumeric coding system for naming these cells.

Some examples of coin batteries that conform to the IEC standard are CR2032, LR1154, and SR516. Sometimes, it is slightly confusing for people to identify the cell battery name. 

Let us take the example of CR2032 to understand the nomenclature!

• The first letter indicates cell chemistry. The letter ‘L’ is for Alkaline cells, while ‘C’ is prefixed for lithium coin cells.

• The second letter indicates the cell shape. The letter ‘R’ is for round, ‘F’ is for flat, ‘S’ is for Square (S), and ‘P’ is for simply ‘Not Round’ cell.

• The reference number of three to four digits on the battery cells denotes their approximate or exact size. In our example, ‘2032’ indicates that the diameter of the cell is 20mm, and its thickness is 3.2mm.

Hence, the CR2032 cell is a round lithium cell battery with a diameter of 20 mm and a thickness of 3.2 mm.

Features of a Coin Cell Battery

Let us discuss some notable features of coin lithium batteries.

• Coin batteries are an appropriate power source for portable equipment and on-the-go electronic gadgets. These facilitate the use of various things in day-to-day life.

• The coin lithium cells have a significant power-to-size ratio and long working life. Also, they have a considerable shelf life of around 7 – 10 years. 

• These batteries are durable and will not hamper the performance in adverse weather conditions. Also, these batteries are not prone to leakage, explosion, or instinctive combustion.

• As long as these cells are not soldered to a circuit board, assembling and removing these cells is very convenient and hassle-free.

• Coin cells have a low self-discharge, so they can hold their charge for a long duration even if not being used. You can continuously use them in a wristwatch for over a year.

Applications of Coin Cell Batteries

Nowadays, we are increasingly using smaller gadgets or portable personal devices. To run these devices, we require batteries that fit in them conveniently. Coin cell batteries are popularly utilised for such small-sized devices.

These cells help us to keep an eye on the time when used in wristwatches. Other common applications of coin batteries include calculators, remote controls, bank card readers, electronic games, digital scales, car keys, and more. 

These are even used in small medical equipment like digital thermometers. For pacemakers, a single coin battery cell can provide an artificial heartbeat for 5-to-10 years.

Besides, coin batteries are suitable for very small or low-power projects. These are useful for testing LEDs and powering electronic tealight candles and disposable devices. Other than single-use (or disposable) batteries, rechargeable batteries are also available in different sizes. However, they have a lower capacity than the former.

Conclusion

The Coin cell battery we use daily is designed to make our lives easier. It is ideal for running portable devices or electronic gadgets. With an increase in the usage of small electronic devices, such types of batteries have become more popular.

Many lithium coin batteries can appear very similar, as they often have the same diameter but a bit varied thickness. To purchase the most suitable coin-sized lithium batteries, it is significant to know which size you require. 

FAQs

Q. Who are the notable manufacturers of coin cell batteries?

Some of the major manufacturers of coin lithium batteries are – Renata, Panasonic, Duracell, Energizer, GP, and Varta.

Q. What are the safety precautions that should be taken for coin cell batteries?

A risk involved with using coin batteries includes accidental ingestion by children because of their small size and round candy-like shape. Therefore, you must ensure that you store and dispose of these batteries at room temperature in an area inaccessible to children and pets. 

Q. What does the expiry date on the coin battery indicate?

The expiry date shows the duration after production for which the battery will function properly, as per the set industry standards. It varies according to the battery type. Notably, it takes around ten years for lithium coin batteries.