Lipo mount for electric skateboard v2

Note:
V1 for this was here: http://www.thingiverse.com/thing:2099034
It broke after a few weeks of use (https://goo.gl/photos/5fpRg7m1fgBkHXUp9)
So I designed a much more rigid part that will probably last much longer.

This is part of a project in which I converted my longboard into an electric longboard for my kid. I mount 4S 5200mAh lipo on it for the kid, but it can hold 2 or even 3 packs stacked if you don't mind the hight. There is room for velcro straps on the sides, but those are n