lithium ion battery box

[awtistiaeth goch]

Hi folks. I now have the siderails and side-locker re-attached to my revoery lorry-to-motorhome conversion. The lovely lockable aluminium box that used to hold the ratchet-straps etc in seems like a good place to mount the 200ah lithium ion battery and DC toDC charger we want to use. If I vent the box, how much clearnce do I need to leave around the battery? I've seen confliciting advice on the internet so far that ranges from none to 100mm.

Thanks/Diolch