Here's a short saga that pertains to battery maintenance.
I have a street rod that for some reason (bad alternator diode, I suspect) will drain the battery if left idle for about 2 weeks. I went looking for a suitable maintenance charger for this short-term storage issue, as well as long term winter storage for my Benz and rod batteries. I also wanted a compact unit that could also provide a full charge, all without any danger of overcharging.
After searching the net, and looking at what was available locally, I found the 'Battery Tender Jr.'. This tiny little unit has been maintaining a storage charge since December on both batteries. It will get used all summer for the rod, and I expect many years service from here on in.
After reading the technical discussion on their website, I think it may convince you too that not all trickle chargers are the same, and that this technology is unique and, so far, quite superior to anything else on the market, IMO. I say this partly because I've actually had a brand new battery dry up on me after being connected to a regular trickle charger for several months.
http://batterytender.com/default.php?osCsid=9ddbb1fd379cd753442343679314c19c