After living with the system for several months,it was clear than I was not going to realize the full potential of the system with the 16 trojan T105 golf cart batteries.
After doing some research into the most bang for the buck, I settled on the trojan L16RE2V 2 V cells. They are rated at 1100 AH @ the 20 hr rate, compare to the golf cart batteries which are 220AH.
Trojan just introduced in march what it calls its Smart Carbon construction for Renewable energy batteries. This is supposed to add 15% to the battery life when used in RE applications.
The problem with buying big batteries is getting them home, so a big part of my choice was that a local battery supplier had 24 of these batteries in stock, and was willing to deliver them for free. Only catch was that they bought them before Trojan
introduced their smart carbon technology, so they were in a position to want to get rid of the old stock. The street price of the batteries is $364 each, but they let me have them for $300 each,so the 15% possible life improvement of the new smart carbon batteries was given to me as a discount, and hopefully by careful maintenance I can get some good life out of them.
An important thing to note here, is the construction of the cells.
The L16RE batteries come in a 330AH 6V version, or a 1100Ah 2V version. The case is exactly the same, and the battery still has 3 cells, the difference is that the inner cells are either series or parallel. The down side is that you have three cells to check and maintain even though it is a 2V cell. Turns out that they make an Industrial battery of 1500AH that is a single cell, but that cost close to $1000 each.
Time will tell if I made the best purchase. Now I need to build a big battery box with vents that will house all of the batteries.