If you are constantly getting inj 7 codes after replacing the injector you should check your wire harness for shorts. I pulled my whole harness unraveled it and checked every wire. I found 2 bare wires and a ground broken. Re-wrapped it and installed it.
If the harness is showing a short follow the wires and make sure none are pinched or shorted together the injector wires all run through 1 ground. It's easy to follow.
If the wires look ok, more then likely it's going to be a PCM problem and will need to be replaced. I had the exact same issue with mine and it was #7 this one seems to go out first. After research it had something to do with a short in the PCM. I sent it in to a place the re-manufactures PCMs I got a new one back installed it and it worked fine. If you send in the factory PCM you get a lifetime warranty. It was a place I found on ebay. It was around 150-200 to have it fixed I can't remember.
Injector problems need to be fixed asap and not driven. Depending on the short it can leave the injector open flooding the cylinders, fouling out the plug, washing out the rings, and damaging the o2 sensor.
The bucking is due to the misfire in #7
The other code is due to a faulty or damged battery sensor. The sensor is under the battery tray it's that little circle thing that sits under the battery, either you have a short or the battery/charging system needs to be replaced.
Dodge's electrical system is very sensitive. A bad battery can cause a lot of problems. As the other guy stated I would get this checked first, and if they are both ok continue on to my other suggestions.