The DSLR Battery Holder 2 from Think Tank eliminates the hassle of fumbling around through your camera bag searching for that extra battery. When the shot is there and you need power right away, this small, compact & efficient folding holder will help you get back up and shooting in no time. It features hook and loop closure and holds two standard lithium-ion DSLR batteries. I've used it to store Canon LP-E6N batteries, Fujifilm NP-W235 batteries, Nikon EN-EL15 batteries, and Sony NP-FZ100 batteries.
Tip: I store fully charged batteries with their electrical contacts facing down into the holder, and once they are discharged I store them facing up. This allows me to quickly identify whether a battery is or is not charged.