Battery Questions (problems), It's Dead Options

[smooth_eddy]

My Optima 34R battery only lasted for 5 1/2 years. I only drive about 1000 miles a year, which may be part of my problems? Anyway, last month I bought a Battery Tender Jr. which will charge the battery, but within one day, the battery looses it's charge. I check battery voltage with a Fluke meter and a it reads 12.34 volts at rest, and 13 volts at 1100 RPM. So I assume this is a good charging voltage?

I have been researching batteries online and have seen many poor reviews for the Optima batteries. Is there a better battery for 914's? Where is the best place to buy a new battery?

Thanks.....

[pbanders]

FWIW, I use a conventional Sears Diehard lead-acid battery, which is what I've used since 1982 when I bought the car. My battery tray is original and has no acid or rust damage. I put the battery on an acid-neutralizing mat, and use treated felt terminal rings to reduce corrosion at the posts. I have taken a wire wheel to all of the chassis, transmission, battery, and fuel injection ground points to clean them for a good contact. I also replaced the ancient copper battery ground strap with a new heavy gauge strap - the old one broke in my hands when I removed it. I have an additional heavy gauge ground wire from the alternator directly to the chassis (normal alternator ground path is through the pivot to the engine, then to the chassis, about a 0.35 V drop path). I have a new rebuilt stock alternator, and I'm using the transistorized replacement from Bosch for the factory mechanical voltage regulator.

Net result is my system voltage is 13.85 V, and my battery stays charged at 12.75 V (after surface charge removal). No leaks, strong starting.