Being a Strobist-style wedding photographer, I use a lot of flashes. Nighttime, daytime, direct sunlight, I’m rarely without at least one or three Speedlights and I need them to recycle fast, especially when shooting the dance floor during the wedding reception. Nothing more annoying than waiting for the flash to recycle and missing key moments. And on the other hand, you’re firing away and when things are starting to get good, you’re flash runs out of battery. So how do we fix this?
Easy, meet my little friends: Sanyo Eneloop NiMH batteries. They are the best thing since slice bread. They’re inexpensive, hold a charge very well, and recharge in like one (Canon 580EX II and Nikon SB-900) to two (Canon 550EX and Nikon SB-800) seconds from a full power discharge. A set of four with charger can be had for $18.95 from B&H Photo Video and an 8-pack for $19.99, but the best prices I’ve seen are at Costco whenever you can find them.
I would recommend using Ni-MH batteries over Lithium Ion (Li-ion) for flashes, as Ni-MH does a better job of handling full-power discharges and is quicker on recycle time. I should note that I tend not to fire full-power flash blasts, but rather try to shoot for 1/4th power for faster recycle and less battery drain. At 1/4th power on the flash, I can shoot an entire wedding before needing to recharge the Eneloop, but YMMV depending on your shooting style.