BATTERY ANOMALY: Part Three: Additional Testing

After another day of charging I did some more tests of the suspect battery using the Centech Meter. This time the battery resistance reading had dropped to 9 milliohms. A big improvement from the 194 reading but,  still three times what I had measured back in 2012. In addition the meter said I only had 335 Cold Cranking Amps available from the battery. Manufacturing spec says it should be 1100. So even though after several charging attempts the battery is really not up to snuff and will need to be replaced.

I then decided to some quick tests of the other batteries in the string using the CenTech meter. Starting with the first (most positive battery in the string:

As the above photo shows this battery had 1404 Cold Cranking Amps available. So at least with this test seems good. Next I checked Battery Two:

   

As the readings above show the results are not as good as the first battery. In fact it only shows 884 Cold Cranking Amps available. Not as bad as the suspect battery but, under the spec of 1100 CCA.
Battery three was tested next:

This tested better than battery two but, not as good as battery one. At 1150 Cold Cranking Amps it was just over the battery specifications but, not by much.

After doing these tests and thinking about the age of the batteries I came to the conclusion that it would be better to change out all of the batteries in the 48 volt string. In addition after doing these test in the confines of the under the cockpit space I decided I would position the batteries differently to make access for future testing easier. The next question is do I go for Lithium Ion batteries or stick with the AGM's?

TO BE CONTINUED