I run 7-10 cameras (depending on how many fail and how long it takes me replace a broken one). AC Delco from Amazon for spring/summer, Energizer lithium for fall/winter. The lithium make a huge difference in cold months.
Mine are all Moultrie, Wildgame Innovations, & Primos brand. This is what i've figured out after years of dealing with these things besides the type of battery for season....
They need strong batteries. Meaning high state of charge. When the camera says it has under 80% battery life, that means it's about to shut off. They will not function (or will have all kinds of errors) with partially depleted alkaline batteries. They won't do that on Lithium and will run them down really far. So replacing ~50 batteries at a time, it sure is a lesser hit to the wallet to use the Amazon AC Delco vs lithium. But since the lithium last longer, they aren't as crappy a value as they seem. A camera that sees little action and is pointed in a way it isn't taking pictures of trees blowing in the wind or other nonsense can easily go for 18 months on a set of lithium - long past when alkaline would fail (and potentially be leaking).
I REALLY notice the difference with the cameras that are set to video and with minimal delay or the ones that take 1,000s of pics of tree branches every time it gets a bit windy. 3x as much stored on a memory card before battery failure with lithium in that case.
As to the "use the solar rechargeable pack" ... that's fine for many, but a lot of us can't/don't want to use. For me:
1. None of this stuff lasts. I have $40 cameras & $180+ cameras. They all eventually leak water or just up & die. I keep the moultrie ones in their steel lock boxes which keeps a lot of sun & weather off them & they still randomly die sometime within 48 months. I have no reason to believe the external battery packs/solar setups would last much longer than the cameras, so spending $ replacing cameras and solar chargers too? No thanks.
2. Mine are mostly for monitoring remote property with no utilities. Getting pics/video of vehicles on private road where they have no business being. I have so many in use because they are arranged so that they overwatch each other. So whoever messes with a camera they see is at least being recorded by one (or more) they cannot see. The added bulk of the external solar pack makes the more hidden cameras easier to spot.
An external solar or larger 12V battery box is as much or more than a mid-range camera. I have to go around swapping out SD cards to see what the cameras see anyway, may as well just swap AAs too since I'm already there....
