I just bought an IPod dock with speakers so i can listen to it at home and I noticed that my Ipod gets charged when I turn the dock off; not only that, but I keep seeing (vaguely) the full green energy bar as long as the iPod is set in the dock. Since I’m planning on leaving my iPod in the dock for extended periods of time, I’m wondering whether this constant chrging will kill the battery.
I used to hear this a lot about batteries - how continually charging them rduces it’s power once you unplug - and have developed a tendency to remove any chargers as soon as batteries are filled. Since I don’t feel like disconnecting the iPod verytime I’m done listening with, I’m hoping batteries have improved and can safely be left charging.
The iPod uses Lithium batteries that are charged with a “smart” controller. These batteries don’t have a significant memory effect, like NiCds used to. Leaving the iPod on the charger is perfectly OK.
Thanks, that’s what I wanted to hear 
Lithium-ion batteries tend to do nasty things like explode if you over charge them. As a result, they require “smart” chargers like what beowulff mentioned.
Lithium-ion batteries have a greater capacity and smaller weight compared to something like a ni-cad. The so-called memory effect of ni-cads is poorly understood by a lot of folks, but how you treated your ni-cads did have a significant effect on how long they lasted. Lithium-ion batteries aren’t so sensitive to that sort of thing. It doesn’t matter as much if you let them go most of the way dead or if you only let them discharge a bit. Unlike ni-cads, lithium batteries will last about the same either way.
The bad thing about lithium batteries though is that they just don’t age well. They’ll lose about 20 percent of their capacity per year no matter how you treat them.
The one thing that can negatively affect your lithium batteries though is heat. The charger will prevent you from overcharging the battery and doing it harm, but if the charger’s circuitry gets very warm and heats up your batteries (along with the rest of your iPod) then you could significantly shorten the life of your batteries by leaving it on the charger. If your charger doesn’t get too warm though then it’s nothing to worry about.
What do you do after several years and the ipod won’t hold a charge well enough? Can you change the battery yourself?
You can, but it’s not that easy.
There are lots of resources on the web that show you how it’s done.
Apple’s battery replacement program. There are probably aftermarket/DIY solutions too.
A few years ago there was this guy who developed a cult following with a video he made telling people the “dirty little secret” that when your iPod battery dies, there is no Apple replacement battery. That was 2003, things have changed.
But you are killing it softly, with your songs.