Charging a dead 12 volt battery

After a long delay, here's the final update:

It worked. After pulling the battery from the car it took the trickle charger about 48 hours to bring it back up to full charge. I put the battery back in the car yesterday. 1st attempt at starting gave me a ton of warning indicators, I turned the car off, waited a couple of seconds, and on the 2nd attempt it fired right up. The hybrid battery had only lost 1 bar of charge in almost 7 months. Left the car ready for a few hours and this time I've backed it into the garage so if the 12 volt dies again at least the jump terminals will be reachable.