These hardware forums are always buzzing about battery life and whether you own an iPod or some kind of Laptop these are most likely Lithium Ion based power packs. Your battery's lifecycle depends on many things such as: storage temp, full discharge cycles, internal resistance, oxidation, chemical decomposition, charge calibration, and so on..... The good news is that what has the greatest effect on how long your battery lasts is in YOUR CONTROLE. Mainly storage temp and full discharge cycles. Sadly laptops run HOT and iPods find themselves in VERY HOT cars or pockets. So for more info here are some useful links. Battery Technology Comparison (See page 8) How to Prolong Lithium-Based Batteries Oh and don't forget to recycle those old batteries. Lets keep those nasty chemicals out of our environment please. A.J.