Summary

Plenty of these around, and there's nothing particularly special about this one.

Mostly I wanted to try out CoffeeSCAD.
http://kaosat-dev.github.com/CoffeeSCad

Instructions

Here's the code.

rows=4
cols=3
size=14.75
innerwall=1.5
outerwall=1.5
base=1.5
height=20

battery= new Cube
size : [size,size,50]

body= new Cube
size: [((size+innerwall)cols)+(outerwall2)-innerwall,((size+innerwall)rows)+(outerwall2)-innerwall,height]

for x in [0..cols-1] by 1
for y in [0..rows-1] by 1
body=body.subtract(battery.translate([x(size+innerwall)+outerwall,y(size+innerwall)+outerwall,base]))
return body

Battery Holder