I have a house in HI (1/4 mi from ocean) and have had battery operated sensors there for just under 2 years. My last trip there (9/12) I noticed corrosion probably due to alkaline battery leakage (Duracell) in 2 of my Everspring HRDS sensors. One was in my garage and the other was the inside of a frequently openned window. I thougth that the one in the garage was ruined because it wouldn’t function after changing the batteries. However after I excluded and included it twice today (10/12), it seems to be working ok. I have read that lithium batteries are less prone to corrosion and leakage and may even last longer. They certainly are a lot more expensive unless you find good deals on eBay. One has to factor in the cost of replacing a sensor if the corrosion/leakage goes too long.
I am in the process of replacing all of my alkaline batteries there with lithum.
I had a job sending out battery powered gps devices to people, and so I sent hundreds of GPS devices out with AA batteries. Never had a lithium battery leak. Frequently had problems with Akalline batteries leaking when they are fully discharged. You might also try Nickel Metal Hydride as they are quite safe.
Hope that helps!