The simple solution is to put the battery compartment in a different box where it can be located at an easy to access area. The logical thing to do is put the test button as well as a temporary silence button here as well.
Total cost to most smote detectors: less than $4
Each year many people are hurt during falls that happen while messing the smote detectors either testing them or changing the battery. Many older people never recover from broken hips and many often die with one year of a hip fracture. This looks like a cheap solution to a real problem.