How are you powering everything other than the camera? To add to /u/SirSocket's reply, since you are using a Canon camera, if everything else is powered by an outlet, you could get an AC adapter for the camera. They can be found on Amazon for around $20 USD. They come with a typical looking AC adapter, but the end that would normally plug into the device is instead shaped like the battery for your model camera, and plugs into the battery slot. A quick look on Amazon shows this.

There, no need to change any batteries. If everything is powered from an outlet when possible, it helps to minimize things that can go wrong.