... when I tried to use it last year to recharge my cell phone. I did realize that the actual lighter worked fine, but clearly wasn't designed to work with today's 12v adapters to provide power to electronics. ....
Mike,
can you charge your phone with an USB source? If so then the easiest way is to buy a USB charger that has a spring-loaded plug at the end. The springs assure contact with the wider rim on the old European lighter sockets.
Your local automotive shops should have them, just make sure it is also long enough.
From Wikipedia:
12-volt cigar lighter receptacle and plug, size A
• Receptacle inside diameter: 20.93 - 21.01 mm (median 20.97 mm)
• Plug body diameter: 20.73 - 20.88 mm (median 20.805 mm)
Most often used in American automobiles.
12-volt cigar lighter receptacle and plug, size B
• Receptacle inside diameter: 21.41 - 21.51 mm (median 21.455 mm)
• Plug body diameter: 21.13 - 21.33 mm (median 21.18 mm)
Most often used in European automobiles, and sometimes as a second socket in American automobiles expressly for DC power connections.
Cheaper then buying a "middle" adapter:
http://www.classiccult.com/vintage-german-cigarette-lighter-plug-nos.html