According to Article ID #61141 the battery of your iPod cannot be removed.
Does this means you cannot change it after a couple of years?
How long do these batteries last, before they become weaker and weaker, and at the end you cannot charge it at all anymore?
From Apple Knowledge Base:
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iPod: How to Check How Much Charge Is Left in the Battery
Article ID: 61141
Created: 1/28/02
Modified: 3/18/02
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TOPIC
This document explains how to check the battery's charge.
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DISCUSSION
A battery icon on iPod's screen indicates the state of the internal battery.
When iPod is charging, the icon changes to a battery with a lightning bolt inside. When iPod is disconnected from the power adapter and from your computer, the progress bars on the icon indicate how much charge is left.
A fully charged battery provides up to 10 hours of playing time. After about 28 days of no use, the battery needs to be charged. If you connect iPod and the battery icon does not animate, its battery is fully charged.
iPod's battery can't be removed.
This document contains information from Help Center, the help system included with your computer.
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Document Information
Product Area: Peripherals
Category: iPod
Sub Category: General
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