That's kind of a short life. I've been using four in rotation for the last four months. I've also started logging how often they gat charged just to get a handle on things. None of mine are up to twenty charges yet, but I'm getting there. The life cycle varies depending on battery quality, load coditions (short high current versus slow discharge) and the environment. Leaving them in a closed car in the summer, or winter for that matter, will significantly shorten their life span for example.
