The battery pack is enclosed in an aluminium shell and is quite rigid. Moreover, it has gone through nail penetration testing as a part of the homologation tests. The pack passed, which is why we have vehicles on the roads. Adding to it, that test is done on the battery in isolation.
The battery is actually a lot safer on the scooter because it is shielded by the chassis on all sides. 2-wheeler crash testing standards which are battery focused do not yet exist hence there has been no formal crash testing conducted. However, the scooter has been through its fair share of accidents during road testing and the chassis, the battery casing and short circuit protection mechanisms ensured that there was no fire in the aftermath. (In case you were wondering, our test riders were fine as well )