
The battery model is CR2025. It is a lithium manganese dioxide battery, named according to the IEC standard. The breakdown is as follows: C - Indicates a chemical battery system with lithium metal as the negative electrode and manganese dioxide as the positive electrode. R - Indicates the battery shape is cylindrical; if it were square, it would be denoted by F. 20 - Indicates the battery diameter is 20mm. 25 - Represents the battery height of 2.5mm. The nominal voltage is 3.0V, the endpoint voltage is 2.0V, and the rated capacity ranges from 140-170mAh. CR2025 typically has a lifespan of 5 years. However, if the manufacturer's production standards are low or quality control is poor, the lifespan may be significantly shortened. Domestic first-tier brand batteries can generally guarantee this lifespan. Under ideal conditions (sealed, room temperature, no moisture, etc.), the lifespan can extend further to 8 or even 10 years. The usage time of a car remote key battery is closely related to frequency of use. The more frequently it is used, the shorter its lifespan. If the remote key battery runs out, the mechanical key can still be used to unlock and start the vehicle. Car remote keys typically use button batteries, mainly three types: CR2016, CR2025, and CR2032. Owners can refer to the user manual for the specific battery model required for replacement. Button-type CR2016 battery: This is one of the most commonly used remote key batteries. Its voltage is 3V, while most car key batteries operate at 9V, so all three batteries must be replaced simultaneously. Examples include brands like Honda, Toyota, Volkswagen, and Mazda. CR2016 specifications: 20mm diameter, 1.6mm thickness. Button-type CR2025 battery: Its usage rate is much lower than CR2016, but some car keys still use it. It is thicker than the CR2016 but offers higher storage capacity. CR2025 specifications: 20mm diameter, 2.5mm thickness. This type is also commonly used in audio remotes. Button-type CR2032 battery: Also 3V, but with a capacity of around 200mAh, making it twice as thick as the CR2016. The 3V-CR2032 lithium-manganese battery follows a lithium-manganese dioxide structure. The positive electrode is chemically stable manganese dioxide, the negative electrode is lithium metal, and the electrolyte is a lithium battery solution. Its shape resembles a button, hence the name lithium button battery or lithium-manganese button battery. Button-type CR2450 battery: This is thicker and larger compared to the other three, with a diameter of 24.5mm and height of 5.0mm. The rated current for CR2450 is 0.2mA, primarily used in low-power electronics. It can provide an output current of 0.001mA to 5mA, with a continuous output of up to 15mA and a pulse output of up to 30mA, meeting the requirements for light, sound, and RF output in small electronic devices. Owners can refer to the user manual for the specific battery model required for replacement.

I remember the battery model for the Mazda CX-4 car key is usually CR2032, which is a coin cell battery of just the right size. I've driven the car for several years and replaced the battery a few times myself. Changing the battery is super simple: use a small screwdriver to gently pry open the cover on the back of the key, being careful not to use too much force to avoid cracking it, and you'll see the battery slot. When inserting the new battery, make sure the positive side is facing up, otherwise the remote won't respond. CR2032 batteries are cheap to buy at supermarkets or online, usually costing around 10 yuan. If the key's remote range shortens or there's no sound when pressing it, it's likely the battery is running low. I recommend checking the battery voltage every year to avoid getting stuck when you're out and having to call a tow truck.

As a new car owner, I initially didn't know the key model. After consulting the repair shop, they told me the CX-4 car key uses a CR2032 coin-type battery. Trying to replace it myself was a bit challenging, especially as a beginner worried about prying open the plastic casing, so I had a professional handle it. The battery model is printed on the old one, making it easy to check. If the remote stops working, don't panic—it's likely just a dead battery, and replacing it will restore functionality. Also, inserting it the wrong way or using cheap batteries might affect lifespan. The battery typically lasts one to two years, so don't skimp on small expenses that could lead to bigger issues. Just ask about it during regular car maintenance—it's hassle-free and safe.

From a technical perspective, the CX-4 car key comes standard with a CR2032 lithium battery, which is a round 20mm diameter coin cell with strong universality. I've replaced this battery before—just gently pry open the back of the key with a small tool, and make sure to align the battery properly without tilting it. After replacement, you usually don't need to reset the key system; simply test the lock/unlock function. Stable battery voltage ensures reliable signal transmission. Avoid using other battery models or non-OEM products, as they may affect remote range and key functionality.


