I'm nearing the finish of my phase 1 testing, and am now looking for replacement batteries. right now, I am using two of these:
http://www.power-sonic.com/images/powersonic/sla_batteries/ps_psg_series/12volt/PS-12180_11_Feb_21.pdf ;. They are on separate contactors, so I can use either or both when flying. I use both when starting. They are two years old, and today when I went flying I noticed that the voltage was getting down to 11.6 volts. after landing, the voltage was up around 12.3 volts. Usually I show around 13~13.6 volts when running. I always use a float charger specifically designed for these batteries when the plane is put away. Usually the float charger shows a slow charge, but when I cam back from flying today the charger was showing a fast charge, meaning that the batteries were discharged a fair amount. Any comments on the suitablitiy of these batteries and suggestions on how to test them out for holding a charge or otherwise deterining their suitablity or not for my plane. I have a 40 amp Nippondenso alternator, and run an Xcom radio, a terra transponder, Dynon D10, Tracys EM2 and EC2, and one fuel pump(at a time unless landing or taking off) that draws around 4 and no more than 6 amps.