Button cells have more life than large batteries. For example, a silver oxide coin cell can last up to three years. Similarly, other cells even have their expiry date of up to ten years. More depends upon the usage and care as well. One important thing to consider is that the shelf life of the product is different. So, the life years may or may not be different when your device is active and inactive. The major reason these cells lasts up to years is that they require low power as compared to flashlights with large batteries. You see, there is no specific durability of these cells as each product has different features. You can check that out in the specifications list.