Help!!! Explosion and smoke coming from intake grill!

[Dgnarvs]

Help!!!

Firstly, please bear with me as I'm only getting second hand details from my bro who's with he car.

Bro took the car to a Bosch service center to replace the battery. Shop said it's advisable to change to S5 DIN100 which has a 100Ah rating. After installing, the car was started and an explosion was heard and smoke came out of he passenger side (right side of the car) intake grill!

After a few minutes, the car restarted fine. The shop checked the engine and saw some rubber tubing detached or with loose clamps. (I suspect those are intake parts.)

Shop thinks its probably some gas residue since smoke is white.

I do hope it's just that and not anything worse. Any one have a similar experience? Any ideas of what actually caused the explosion/smoke?