Sometimes it is difficult to gauge scale on your CAD model. Small objects can seem huge because you have zoomed in so close in order to model the feature.
I have found the following technique particularly helpful in modelling human scale products, or more specifically - objects and features within the envelope of your monitor screen. Even large products tend to have smaller human interfaces so this tip could be useful to a lot of people
Go to one of the orthographic views. First find a reference length. In this case the length of the battery is 106mm
Then I set my callipers to the reference length (106mm)
Zoom the view to match the length on your calliper. This calibrates the size on the computer screen to the real world
After matching the length, do not move or zoom your view. Create a new view and name it 1:1 scale
Voila! As long as you dont zoom in, you should be examining a calibrated 1:1 scale model on your monitor. Just rotate the viewport/camera to observe from all angles. At the very least this method can save you a few printouts to confirm scale. I use it to quickly gauge the ergonomics of a CAD model before sending to rapid prototype
I believe that these techniques are applicable to Alias and Rhino as well