I laser cut some covers that place an acrylic wall between each of the busbars of my battery, as well as covering the top. They are designed to keep a falling screwdriver, wrench, or bolt from bridging the bussbars and causing “excitement”. I have a lot of air holes to try and allow a normal amount of air flow, as well as exposing the bolts and screws for occasional tightness checks.

You can download the textual openscad design file here:
battery_shield.scad

Or, you can just download the PDF files if you want to laser cut them exactly as they are:
battery_shield
battery_shield_reversed

A “how to assemble” video is here:

Youtube Video link

Acrylic could be a bit brittle for this application, and using 3mm craft plywood could provide a bit more impact resistance. However, the covers are inside the “sidewalls”, plus the batteries will be mounted sideways and the current “top” will be mostly protected by insulating foam in my battery boxes,so I chose to go with the less smoky option. (Plus, I think the semi-transparent nature of the acrylic just looks cooler.)