What is the battery model for Volkswagen car keys?
2 Answers
The battery models are CR2016 and CR2025. These are lithium manganese dioxide batteries, named according to IEC standards. The naming convention 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 square, F is used instead); 20 - Indicates the battery diameter is 20mm; 25 - Indicates the battery height is 2.5mm. The nominal voltage is 3.0V, endpoint voltage is 2.0V, and rated capacity ranges between 140-170mAh. CR2025 typically has a lifespan of 5 years. 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 interference), the lifespan may extend to 8 years or even 10 years. The usage time of car remote key batteries is closely related to frequency of use - the more frequently used, the shorter the lifespan. When the remote key battery is depleted, the mechanical key can be used directly to unlock and start the vehicle. Car remote keys use button batteries, primarily three types: CR2016, CR2025 and CR2032. For specific models used in each vehicle, owners can refer to the battery model specified in the user manual for replacement. Button-type CR2016 battery: This is one of the most commonly used car remote batteries. The battery voltage is 3V, while most car keys operate on 9V power, requiring replacement of all three batteries simultaneously. Used by brands like Honda, Toyota, Volkswagen, Mazda etc. CR2016 specifications: 20mm diameter, 1.6mm thickness. Button-type CR2025 battery: Its usage rate is much lower than CR2016, but still used by some car keys. Thicker than CR2016 but with relatively higher storage capacity. CR2025 specifications: 20mm diameter, 2.5mm thickness. Also commonly used in audio remotes. Button battery CR2032: Also 3V voltage but with about 200mAh capacity, making it twice as thick as CR2016. The 3V-CR2032 lithium manganese battery has lithium-manganese dioxide structure. The positive electrode uses chemically stable manganese dioxide, negative electrode uses lithium metal, with lithium battery electrolyte composed mainly of dimethoxyethane, propylene carbonate and lithium perchlorate. Shaped like a button, hence called button lithium battery or lithium manganese button battery. Button battery CR2450: Relatively thicker and larger than the other three models, with 24.5mm diameter and 5.0mm height. The rated current value is 0.2mA, mainly used in low-power electronic products. Generally can provide output current from 0.001mA to 5mA, with continuous output up to 15mA and pulse output up to 30mA, meeting requirements for lighting, sound, RF output etc. in most small electronic devices.
When replacing the key battery for my Volkswagen, I found it uses a CR2032 3V lithium coin cell, commonly found in models like Golf and Passat. No professional tools are needed—just use a fingernail or small coin to pry open the key's back cover to access the battery slot, making the process very simple. These batteries are easily available in supermarkets or online for about one yuan each. After replacement, it typically lasts one and a half to two years. It's advisable to check regularly and replace it promptly when the remote control distance shortens to avoid startup issues due to sudden power loss. For different models or those with smart key functions, the battery type may vary slightly—for example, some newer ID series use CR2025—so it's best to first open the key to confirm the model label or check the manual to prevent incorrect installation. DIY replacement is cost-effective and a handy skill to learn, but avoid forcing the case open to prevent damage. This battery type is widely compatible across Volkswagen models, and after replacement, the button response becomes much more responsive.
