There's one thing I wanted to mention about AA lithiums. They don't seem to take the cold very well. I have an outdoor thermometer transmitter. Last winter I had alkalines in it, but they started getting intermittent when it got really cold (like below 0). This year, I put lithiums in, hoping they would last longer. Not a chance! As soon as it dropped below about 30, it started cutting out occasionally, and would come back when it warmed up. Since it's been consistently cold, they haven't worked since.