I found that many battery cases are designed around standard primary (non-rechargable) cells, these often are slightly bigger than rechargables leading to a very tight fit.This battery box have been optomised for rechargables and will also work for primary cells.The open side allows you to see how many are in the box without taking the lid off.Models for 4, 6, 8, 10 and 12 batteries are supplied.

Designed for ease of 3D printing and does not require supports.