As promised about a week ago i have attached a photograph of the battery
carrier we use in Australia, it is attached to the main fuselage tube
with either cable ties (zip ties) or with super clamps (special
industrial hose clamps). The breaking strain with each cable tie is 54
kg's and we use 6 of them, so it will never come off.
Not shown in the photograph, we attach the battery into the carrier
using cable ties to hold it in, i drill two holes on the vertical strap
on each side of the holder and thread cable ties into them, when
tightened it pulls the battery back into the holder. The inside of the
holder is lined with rubber so it is a nice tight fit. We have never had
a cable tie break or had a battery come loose.
When fitting the battery for the first time just lay it in loosely as
we move it up and down the tube to get the Center of Gravity correct,
once it's in the right spot mount it permanently. I do not recommend
bolting or pop riveting the carrier to the main tube as this may weaken
the aircraft.
I hope this information helps
Thanks Michael Coates X-Air Australia