Subaru owners often encounter the frustrating issue of their key fob batteries draining faster than expected. While it’s easy to assume that simply using the key fob less or that “air” exposure is the culprit, the reality is often more nuanced. Let’s delve into the factors that affect your Subaru Key Fob battery life and explore whether humidity, rather than just air, plays a significant role in their depletion.
The idea that air itself is the primary cause of lithium coin battery drain, commonly used in Subaru key fobs, is a misconception. Many batteries, including AA and AAA lithium batteries, are not hermetically sealed and are designed to function perfectly well in open-air conditions. If air exposure was the main issue, these batteries would have significantly shorter shelf lives and require specialized packaging.
However, batteries do have a shelf life and will self-discharge over time. Factors like temperature and, crucially, humidity can accelerate this process. Think about where your Subaru key fob spends much of its time: in your pocket, in your car, or perhaps left in places with fluctuating temperatures and humidity levels. These environments can be far from ideal for maintaining optimal battery performance.
Humidity, in particular, is a significant factor in battery drain. Lithium coin batteries like the CR2032, frequently used in Subaru key fobs, are susceptible to increased self-discharge in environments with high humidity, especially above 75%. Many regions experience such humidity levels, especially during warmer months or in climates without consistent air conditioning. Humid air can lead to corrosion or internal shorts within the battery, accelerating the discharge process.
The packaging of these batteries also plays a role, but primarily for safety rather than preventing air exposure for battery longevity. Modern battery packaging, often blister packs, is largely driven by child-resistant requirements. While some batteries are double-sealed for extended shelf life guarantees, this is more about maintaining freshness over a decade rather than preventing daily air exposure from draining the battery in your key fob. The packaging you typically see on single or multi-packs is more about preventing accidental ingestion by children, a crucial safety standard.
Therefore, while “air” in general isn’t the enemy of your Subaru key fob battery, humid air certainly can be. The temperature and humidity fluctuations that key fobs endure daily likely contribute to the quicker-than-expected battery life many Subaru owners experience. To prolong your Subaru key fob battery life, try to minimize exposure to extreme temperature and humidity changes. Keeping your spare key fob in a cool, dry place and being mindful of where you leave your keys daily can make a difference. Understanding these factors can help you better manage and anticipate your Subaru key fob battery replacements.
