In order to ascertain which 9V battery was the best to be used for operating the AIM-8 unit, a series of tests were conducted during the months of November and December (2000) on popular alkaline batteries. The results of the tests are shown in figure 1 (below), but the names of the batteries not recommended for use in the AIM-8 unit have been omitted from the chart. For the test, a circuit simulating the current drain of the AIM-8 operating continuously ( No Sleep Mode ) was created. Each of the batteries tested was placed in the same mock-circuit and had its voltage measured by the same digital voltmeter. All of the batteries were tested once, except for two batteries, which were tested twice to verify the quality of the test. The batteries tested were chosen based on customer inquiry and availability. A list of the ones tested is shown below:
Please note that the entire life of the battery is irrelevant in this study, because the AIM-8 unit cannot run on a power supply of less than approximately 5.6 volts; therefore, on figure 1, the AIM-8 threshold voltage is indicated by the yellow, dashed line, and the lifespan of a battery 'as seen from' the AIM-8 unit is the time measured from the origin of the graph to the intersection of the AIM-8 threshold line with the voltage-time curve of that battery.
The batteries recommended for use in the AIM-8 monitor for 8 to 24 hour recordings, based on the test results, are the Rayovac Maximum and the Energizer Titanium. BIT has decided to include one of these two types of batteries in every AIM-8 System Package because of their long 'AIM lifetime.' Based on our study, the Energizer Titanium and the Rayovac Maximum can be active or operate in Wake Mode for about 9 hours and 10 hours, respectively, which is enough life to take about 24hours worth of data.