Loud POP under front end when supercharging

[Walt14]

Has anyone experienced a loud POP while supercharging? I had it happen twice yesterday.
This is only my second time using a supercharger. I only needed a 20 mnute charge to get to my destination with battery to spare, Also heard/noticed the under the front end cooling fan kick into high but I am going to guess this is normal for supercharging given the charge rate was apporximately 700km/hr and a lot of heat was generated.

 

[compu85]

It's the battery pack enclosure expanding... it's sealed, so it can go pop like a can lid as the pressure changes.

 

[Adrien]

Yep, pretty normal, but can be worrisome if you're not expecting it

 

[zhu-]

Yep it's normal. It's the metal flexing from the heat - like some baking pans inside an oven. It normally happens during supercharging and with the weather getting warmer it's happened once during driving too.

 

[CAAD]

Yes it also pops when you're driving which is more disconcerting because it feels like you hit something.