[Al Skierkiewicz]

Guys,
We chose the 7.5 amp/0.4C discharge rate as it gave an fairly accurate calculation of the design AH rating for the battery while using a test that lasts a little over two hours. We experimented with adding a shunt load to increase the discharge current and as expected the AH rating went down nearly identical to published curves from the manufacturer for the higher discharge rate. Remember that the 18 AH rating is generally accepted for discharge rates in 0.1 C range. Discharge rates above 0.4C will give quicker results but will not display anywhere near the rated AH.