A battery is an electrical power source with internal electrochemical cells. Current flows from the cathode (positive terminal) to the anode (negative terminal), which generates a specific amount of electricity. An external load, like lamps or electronic circuits, is placed between both terminals, so they will light up or operate as intended.
For convenience, rechargeable batteries are commonly used to operate smartphones, flashlights, and other devices. However, disposable or single-use batteries are still popular. Cylindrical batteries are the most popular among consumers of different sizes, such as triple-A, AA, and D. Button cell batteries are the most compact form of battery with CR-prefix for the lithium-based version.
Button cell batteries
Button cell batteries are small and coin-shaped, measuring between 5 and 25mm in diameter. Stainless steel acts as both the positive terminal (cathode) and the bottom body, while the negative terminal (anode) is a metallic top cap, made of lithium or zinc.
Button cells are usually used for pocket calculators, wrist watches, computer motherboards, and car keys. Button cell batteries are disposable and consisted only of a single cell. Lithium button cell batteries have CR-prefix, while silver batteries have SR-prefix.
Compared to lithium cells, button cell batteries with silver cells promise a more stable output voltage. Zinc-air button cell batteries offer higher capacity, but they will dry out in less than a month, after being removed from packaging.
Based on its naming, CR2025 is a lithium battery, 20mm in diameter and 2.5mm in height. It’s a 3V battery with 170mAh capacity, but this may vary slightly depending on the manufacturer. It’s a very common form of a button cell battery and you can find CR2025 batteries easily in many stores.
Due to its huge popularity, CR2025 is used in many devices, including car keys, computer motherboards, medical devices, LED lights, door chimes, portable gaming devices, and toys. Because it’s very compact, CR2025 is more suitable for devices with limited space for the battery compartment.
Battery life depends on usage, but if used intermittently like in car keys, CR2025 batteries should last for 3 years or more.
CR2032 is a thicker lithium button cell battery, 20mm in diameter and 3.2mm in height. It also has the same 3V of voltage output, but a higher capacity at 240mAh. It’s more suitable for devices than need longer service life, such as security system panels and server motherboards.
Despite being slightly thicker, CR2032 is still very compact and versatile for many purposes. Its average shelf life is up to 10 years, just like most lithium button cell batteries, especially if stored in a dark, dry, and cool area. Battery life depends on usage, but with intermittent uses, like in-car keys, CR2032 batteries may last up to 5 years.
Both CR2025 and CR2032 are 3V lithium bottom cell batteries with identical diameters of 20mm. Thanks to their compact dimensions, CR2025 and CR2032 are suitable for many portable devices, including heart pacemakers and glucose monitors. Thickness is a noticeable difference between both batteries, with CR2025 at 2.5mm thick and CR2032 at 3.2mm thick. CR2032 has a larger internal cell with a higher capacity at 240mAh, while CR2025 offers 170mAh due to its smaller dimension.
As long as the battery compartment could fit both form factors, you may use CR2025 and CR2032 interchangeably. If your device is designed for CR2032, you may fold up a small piece of aluminum foil to fill the extra space under the battery’s negative terminal and use a CR2025 battery instead. Because CR2025 is more easily found in stores, it’s a simple workaround to consider.