I can finally report on the battery life of the Energizer Advanced Lithium Batteries given to me in late January. I wrote about them on February 4th, and put them in my Canon EOS 5D’s battery grip a week or so after that. They worked until this past Saturday evening, April 25th. When I did the tally, I saw that I’d taken 1,872 photos with them. That’s not a typo. The vertical grip stayed on my 5D all the time, from the time I put the batteries inside it to the time I took them out, and that’s how many photos I got with the batteries.

While that battery life is very impressive, given the 5D’s 500-600 shot battery life with one of its single rechargeable batteries, or 1,000-1,200 shots or so with two rechargeable batteries in its vertical grip, it doesn’t tell the whole story. There are a few things I need to clear up first:

• During these past few months, I’ve been shooting mostly landscapes. That means I didn’t take lots of photos in one sitting, which would have drained the batteries faster. I would expect that if I shot events, the battery life would have been significantly less.
• For some reason, and I’m still not sure whether my vertical grip is to blame or the batteries, the battery life sensor kept giving a low battery notice the whole time the batteries stayed on the camera, from the time I put them in to the time I took them out. Sometimes the battery life sensor would even flash the really low battery signal, indicating the batteries only had a few shots left in them. Regardless, they kept on working until Saturday evening. Not sure whether this was because the camera expected 1.5V out of each battery, not 1.2V, or whether my battery grip, which had been sitting in a box, unused, for several months before this, is at fault, but that was my experience.
• Related to the two bullet points above, the batteries gave out while I was shooting an event. It’s possible that they would have lasted even longer if they hadn’t been put through prolonged, continuous use. It’s also possible that if I stick them back in the camera, they might have enough life in them to let me squeeze off another several shots, but that would go against the conditions of my test, where I wanted to see how long they lasted without taking them out of the camera.

Whatever your mileage may be (and I encourage you to do your own testing), I’m very impressed with the battery life. While it was a hassle to keep the vertical grip on my camera the whole time (I prefer to shoot without it unless I’m doing events), it was an interesting experiment. I would recommend keeping a set of these batteries in your bag as a backup, just in case your regular batteries run out of juice. They have a long shelf life, and they won’t self-discharge like rechargeable batteries.

I also promised in my initial post that I would use them in my 580EX II speedlite. I’m keeping that promise. I’ve been using them in it since February, and they’re still doing fine. Again, I haven’t used the speedlite very much, because I’ve been shooting mostly nature stuff, but I did shoot a wedding recently and it worked flawlessly the whole time. I’ll let you know when those run out and I’ll tally up their shot life, too.