I went to start the car yesterday and no dice. Starter just clicking away. Noticed battery voltage at about 9 volts. I suspect that either the optima has gone bad or more likely culprit is the battery tender. I put another charger on the battery and let it run for about an hour and viola it fired up. I plan on checking to see if it restarts today before ordering a new battery. Went for a 20 minute ride (first one this year). What a blast! Even after all these years, the car still puts a smile one my face when driving it. The battery is 11 years old and has served me well. Never had an indication that battery was beginning to degrade. I have always used a battery tender. I seem to remember readings that the gel batteries tend to just fail with no warning signs. Can anyone confirm that?