The battery life of your nose trimmer may be different than the battery life of another trimmer. Whether you’re using a normal battery, like AA, or you’re using rechargeable batteries factors into the battery life as well. A brand new AA battery may outlive an older rechargeable battery that has been used repeatedly over a while. The efficiency of the trimmer’s motor will also play a huge part in how long the battery will last. A powerful motor won’t usually have to run as long because it will get the job done more quickly, while with a weaker or more delicate trimmer it may seem like the battery dies or runs out of charge more quickly because you need to spend extra time using the trimmer to achieve the same effect. If your trimmer has a lithium-ion battery, you can expect it to last for anywhere from two to three years before needing to replace it.