No, not 15% a day. I read a FAQ the other day that said about 30% a month, I think. The FAQ said that if you don't use your batteries often you are better off with NiCads than NiMH. Ions might have an effect since charged particles in the air would present a slight current between the positive and negative terminals. So there could be a correlation, definitely. Also with humidity, same principle although I'm not aware of the variables. But I think that the discharging of rechargables is due mainly to chemistry, etc. internal to the cells, otherwise your alkalines would discharge at similar rates, and they certainly do not. I don't think you should use rechargables in remote controls since the usage is so relatively slight. I always use alkalines in my remotes and I have to change them very seldom indeed. Rechargables will work in your flashlights and if you use them allot, sure, use them. If you use them seldom, go with alkalines. I have rechargables in my bike light but in utility flashlights that I use only occasionally and for a few seconds, it's alkalines for me...