I've been tinkering with a race quad lately, and I quickly realized how much abuse that a bottom mounted lipo has to take.
Even just a tumble through the weeds has left scrapes, cuts and dings on my 6s lipo batteries. It's just a matter of time before a puncture happens and the fire is let out.

I designed this simple case, built specifically for the 6s 1300mAh CNHL lipo, to hopefully negate any harmful battery damage due to collisions or tumbles when crashing.
It also doubles as landing feet to stabilize the quad during take off and landing.

You will need a spare grippy battery pad that's 30mm wide (or less) to effectively use this holder. The TPU alone isn't grippy enough to keep the battery snug.
There is a 30mm wide recessed channel cut into the top side of the case for an adhesive battery pad to be attached.

If the fit seems too tight for your battery, don't continue to force the battery into the case it may become jammed in there and very difficult to remove. There is a relief hole cut in the opposite end of the case to gently push the battery back out (never pull on the leads). Fit should not be an issue, but if it is, check your print settings/calibration and re-print.