I use velcro instead of silicon. Stick a piece of the "Loop" side to every battery pack and a piece of "Hook" side to every Rx.

Now, with every new plane, just cut an inch or two of velcro and attach the "Hook" side where the battery will go and the "Loop" side where the Rx will go.

It holds the items in place and provides protection from vibrations AND it makes them easily removable and replaceable.

The only thing you need to watch out for is installing the battery inverted (I.E. Placing the battery in a low-wing plane, then flipping the plane over so the velcro is on top) as the combination of weight, gravity and vibration could cause it to come un-stuck.