Good info, but the prices are extreme.  Go to e-bay and do search for ‘Odyssey battery’.  You can buy the PC680 new for $50-$60 instead of $129. 

 

Yep, just bought one from "odyssey_world" on Ebay for a buy it now price of $57.  It was stuffed in my mailbox 3 days later.  

 

Rusty