If you're going to purchase a cordless tool, then you should really think about getting one with Lithium ion batteries. They cost more, and it's easy to think you could just buy a cheaper model and get a spare battery, but it's not the same. Lithium ion batteries are a true hassle free solution.
When you do something processor intensive, plug in the charger. Not only because this usually triggers a higher performance setting and give you more horse power to play with, but because when the battery is discharged at maximum rate it's more probable to overheat, and heat is a great enemy of Lithium-Ion.
Therefore, the key to long iPod battery life is to only charge it when you have to. And remember dead iPod batteries are those that lithium ion stocks won't hold any charge at all. An iPod battery with some charge left can hold some charge can still be useful, but you will still want to consider purchasing an iPod replacement kit.
When it's time to buy a new lithium ion battery, be sure you're buying one that's new (as in recently produced). Just like fruit has a shelf-life, so do batteries and just like you want to buy fresh produce, you also want to invest in "fresh" lithium ion cells. Check the date-code on the battery or packaging to ensure you're not buying a pack that's been degrading for a year on some shelf.
There are some concerns when it comes to these high powered batteries and how good they are for the environment. But all hybrid batteries are set to be recycled (Toyota has a $200 bounty on each Lithium battery stocks pack), and so unlike some lead batteries from conventional cars, they shouldn't end up in landfills.
External effects can be a radiator in your room or direct sunlight, or just simply a mind boggling ambient temperature. A Lithium mines Ontario-ion cell loses 20% of its maximum capacity in one year when it's stored on 40 degrees Celsius and full charge. Not too many people have 40 C in their room all year long, but what about internal heat sources? If you use your notebook from AC power, you're keeping it fully charged, which it doesn't fancy, and on about 40C.
You cannot use the phone whilst initially charging. You can use the phone whilst charging even during the initial charge with no damage to the battery.
And that's about it; not so hard, right? So, although lithium ion batteries might keep us on our toes, utilizing these few simple practices will help you keep your batteries performing at their peak for a whole lot longer. Respect your stuff and in return you'll enjoy really great results.