This is the type I purchased on Ebay last year. It's versatile because it can hold AA, AAA, AAAA or CR123A size batteries and you can clip them together, they also come in different colours. They aren't waterproof but they do keep things organized and prevent short outs.

I've got a dozen or so to hold my stock of AA and CR123A batteries but carry 1 pack of 4 AA batteries in my daypack.