Hi, All. I'm getting condensation drops from my PV battery box's hydrogen vent, landing on my batteries. Any suggestions on avoiding this?

The box is indoors, with an ABS plastic 2" vent running vertically six feet to the ceiling then four feet through a well-insulated attic and then two feet above the roof, before ending in an upside-down 'U' to prevent rain/snow entry. It's an eastern Ontario location with cold winters.

Is this a common problem? I guess one step would be insulating the vent within the attic? Anything better I can do?

Thanks,
...Terry