These should work okay. Going to AA, you would be able to use the Lithium Ultimate AA batteries in colder weather. These test out at 1.79 to 1.83 volt. They are high voltage. This is why they last longer in cold weather. On the down side, dropping from a "D" or a "C" battery to the "AA", your are greatly reducing battery storage capacity, (reducing the length of time a battery would last). As an example, suppose your vehicle has a high cranking amp battery (1000 amp). You remove this and install a lower cranking amp (750). The 750 would not crank the vehicle engine over as long as the 1000 in cold weather. For a temperary trial, cut light weight card board from a cereal box etc., building a tube for each set of batteries that are installed end to end. You would have to build enough for each row of batteries in the camera. Add a metal spacer or spring to make up the additional battery length for the shorter AA batteries. Now, put packing around these tubes, once they are installed in the battery compartment, making sure the tube assemblies line up with the battery contacts. Moultrie D55-IR and SpyPoint IRB would require 3 tubes each, just mentioning cameras I have as examples.
If I remember correctly, this was mentioned on one of the trail camera forums a year or two ago. Checking at that time, someone had them listed on EBay.
I did a search on EBay for "battery adapters". There are lots listed for various conversions. Very reasonably priced. Good luck.
Last edited by littlearrow; 10-24-2012 at 09:30 AM.