So, my dSLR journey started with a starter Canon XSi dSLR that I used for about a year, and then I upgraded to something else last fall. Well, I decided to check and see if my XSi was still operational, and I was pretty surrprised to find out that the Li-on batteries were still good-to-go after 8 months of non-use. I even tried re-charging them, and they were green on the charger, and the camera also showed full charge for the crude battery life indicator. As you can tell, I'm not quite used to Li-on batteries retaining their charge over such a long lay-off. I was told that they had a long shelf life, just didn't have a chance to see that characteristic confirmed until just now. I'm used to the NiMH AA rechargeables that required charging up after a month of storage (though some of the newer NiMH batteries I've bought have a longer shelf life now, as I tend to only use them for the flash unit these days, and a point-n-shoot camera). Did some reading on Li-on battery technology, and they recommend a 40% charge capacity if you intend on letting them sit on a shelf, but unless you have a fancy schmancy charger, it's hard to tell how much charge a battery has in it. Plus, how would you discharge a Li-on battery to get down to such levels if you don't intend on using the dSLR camera to shoot photos/videos (and burning up actuations on the shutter or the sensor)? Storing them in fully charged state can cause internal corrosion, and if their charge is depleted, it can render them un-rechargeable. The flip side, at least the batteries aren't super-expensive, and if they start to perform unreliably after being on the shelf, just get new ones.