powering a nikon d40 from an ac outlet

I have been shooting a lot of time lapses lately. The biggest problem with that is battery life. I have a very ghetto hack to power the camera from a cell phone charger, but I am looking for a more permanent solution. I found a fotodiox battery grip on amazon that has an internal battery, and is able to charge from the wall. Getting the right answers out of the vendor has proved to be difficult, so I’m afraid that I may just have to buy it and try it. Does anyone out there in internet-land have this already? And can anyone tell me if it will run from ac power? I am looking at multiple day long shoots, so changing batteries (and bumping the camera each time) just isn’t an option.


Here’s the link to the grip – Any opinions?