Our testing showed some interesting data. We found seven models: Duracell, Duracell Ultra, Energizer, Energizer e Titanium, Radio Shack Enercell, Radio Shack Enercell Plus and Rayovac Maximum Plus. Alkalines are readily available, moderately priced and have excellent shelf live. Running the tests twice allowed us to average out variability in the batteries.Īlkaline batteries are the baseline against which other battery technologies are compared. We tested four batteries of each type from each manufacturer and our jig ran two batteries in series, simulating actual usage. In addition to alkalines, we also tested rechargeable alkalines, Ni-Cd, Ni MH and lithium technology. We bought all the name-brand AA batteries that we could find at local retail stores, including Duracell, Energizer, Radio Shack and Rayovac. Unlike other testing that just shows how long a battery lasts, our jig also allows us to make some inferences based on the battery voltage curve as the battery is used. The PC recorded data to the nearest millivolt. The custom device has a 24-bit A/D converter with an accuracy of at least 0.002 percent. With this information, we designed a test jig with a two-cell battery holder, a 5.9-ohm resistive load, a custom electronic device for measuring the battery voltage and a PC logging voltage measurements once a minute. This means that battery depletion accelerates as the battery voltage drops, at least for the GPS. One interesting fact we learned is that the GPS power usage goes up (from 378 mW to 482 mW) as the battery voltage drops, whereas the VHF radio power usage went down (from 181 mW to 66 mW). However, these devices are similar in power requirements to aviation units.īefore starting our tests, we measured the battery current used by each of our test devices and we used this data to calibrate the GPSs onboard battery gauge. The testing was originally done for our marine division so the GPS and VHF were marine units. We chose three applications for our testing-a flashlight, a portable GPS and a handheld VHF. We limited our testing to AA batteries, the most often-used size. Even flashlights are following this trend, with incandescent bulbs being displaced by brighter, less power-hungry LED-based flashlights.įor our testing, we set out to compare battery chemistries in different applications to see which types are best suited for which applications. Not only can manufacturers cram more stuff into smaller spaces, but the integrated circuits in the devices require ever less wattage to operate, thus increasing battery life. Modern portable electronics are power conservative and growing more so by the day. With so many choices, is it worth the trouble and expense to seek out other battery types or will you do as well with off-the-shelf alkalines? And if the latter is true, which alkaline is the best buy? In addition to the ubiquitous disposable alkaline, there are also rechargeable alkalines, lithium manganese dioxide, nickel-cadmium (Ni-Cd), nickel-metal hydride (Ni-MH) and lithium ion (Li Ion) cells. These days, there are more battery chemistries to choose from than just alkaline. Redundancy or not, you still buy lots of batteries. Even so, youre sure to carry plenty of battery powered devices in the airplane: several flashlights, a back-up portable GPS, a VHF radio. You probably have dual alternators and perhaps even dual batteries, so electrical redundancy is all but a done deal. If you fly a state-of-the-art single-engine airplane, lucky you.
0 Comments
Leave a Reply. |