CD Music to an MP3 Player...

Finally I got it right.. oh sigh...

I copied the CD's, without protection, to "Microsoft Media Player 9", in W2000... Then processed the music into mp3 with "WinLame"... Then to the MP3 unit... Easy as scratchin' an itch in the middle of your back...

But now I'm concerned that I will be on a job, and suddenly the MP3 player's battery will run out, and I'll be without tunes for the rest of the day... I do so need my tunes on painting jobs.. the music blocks-out the crazy stuff people say...
Is there a way to plug-in an auxiliary battery to an MP3 player, should its battery die?..
Is there a particular MP3 player that will run constant for days on a charge?..
What is the most reliable MP3 player in the world?..
What are the very best earphones?..
What are tomorrow's winning lotto numbers?..