Ipod batt. won't charge

This is always tricky with 1st generation iPod touches. After a while they can't handle the new software anymore and some functions won't work anymore. Maybe try to downgrade the software. Otherwise you should probably get a new iPod.

hi,
Your ipod has problem with its battery. No other way other than replacing the same. The following Video will help you to open the ipod. Check the part number for the battery and find a new one with the same part number.
ok

be sure that your computer recognizes the ipod, and if you are using a wall charger than consider replacing it.

Try charging it with an AC adapter.

If this doesn't work, it's likely that the battery is simply old. I think your model of iPod is a 1st gen Nano, in which case the battery has probably neared the end of its life.

See this page on how to get it replaced by Apple:

http://www.apple.com/support/ipod/service/battery/

Or, if you think you've got the skills, you could try doing it yourself:

http://www.ifixit.com/Guide/Repair/iPod-Nano-1st-Generation-Battery-Logic-Board/431/1

Does the screen light up and you see the charging logo at least or is it just black? If you see that battery logo, but it never turns on, you have a broken battery. If it stays black alltogether you have a broken logic boardIt's not too hard to replace the either part yourself. Here is an iPod Repair Guide that shows how to open an iPod. Parts are easily available on Ebay. If you want somebody else to do it for you go to iPad Repair

This is because you are using different generations.

If the dock was only meant for 1st generation, then itwill only charge 1st generation. It's how they make their money.

Batteries can only take a finite number of charges and they degrade over time.  A 1st gen IPOD is at least 5-6 years old.  The battery is probably bad.  You can buy a replacement battery from Sonnet Technologies (www.sonnettech.com).  It comes with installation instructions and is really easy to replace.

Do the 5 R's - any mp3 player - not just iPod - is prone to acting goofy on low batt
http://www.apple.com/support/ if you need further explanation

Start with these five simple solutions: Reset, retry, restart, reinstall, or restore

http://www.apple.com/support/ipod/five_rs/

If you need more assistance let me know. I'm here to help.

See:
iPod with color display User's Guide

Exploring the iPod

Or download from here.