Although rechargeable hearing aids are growing in popularity, the vast majority of hearing aids today still operate off of traditional hearing aid batteries. These batteries can be divided in to 4 different “size groups”, ranging from smallest to largest: Size 10, 312, 13, and 675. In general, the larger the battery, the longer its lifespan will be, though actual lifespan will vary depending on a number of factors. High-end hearing aids which utilize all of the latest technologies will invariably consume greater power from batteries and diminish overall lifespan, so it would be wrong to assume that the more expensive hearing aids are going to have a better battery life. Update 2/1/14: If you’re looking to get great battery life from your hearing aids, you might look in to the VFusion system.
At the time of this post, the most popular battery size is probably the 312 or 10, as these batteries are smaller, and are used in the more discrete devices that most people demand. Size 13 is still quite common among larger in-the-ear and behind-the-ear instruments, and 675 is usually reserved for only high-powered behind-the-ear devices. As stated above, the actual battery life will vary greatly, but a rough breakdown can be seen below:
Many people are surprised at the short lifespan of hearing aid batteries, but it is important to remember that these batteries are typically working 12-18 hours a day, and they are powering sophisticated technology. Although the idea of changing batteries so often can seem daunting, keep in mind that hearing aid manufacturers are sensitive to this, and are making it increasingly easier to perform this task. In addition, many providers include an annual or sometimes even lifetime supply of batteries with the sale of hearing instruments to encourage use and reduce recurring costs for hearing aid users.
While a long battery life may be desirable in whatever hearing aids you purchase, it is not a factor that should play in to deciding which device is right for you. Hearing aid batteries are completely inconsequential in the primary goal of helping you hear better, and should be treated as such.