If there is, I haven’t found it, either by looking around the engine bay or by reading the manual.
Currently (no pun intended),my CTEK is clipped to a nut on the top of the near side suspension tower and, of course, the battery.
As the car is garaged, I’ve been able to leave the bonnet propped open. If any hydrogen were to be generated, it should dissipate quickly - I hope!
I was surprised to see that the battery on my car is designated for “stop start” systems, even though there’s no such system fitted to my Spider. Luckily, my CTEK is rated as suitable for such, otherwise it would have been back onto the Amazon website for a replacement charger and another dent in the bank balance.