Yes, though note that the battery won't fit inside the system as the smaller ones do:
If you have a 65W adapter, a 90W will charge the battery faster but isn't required.
In addition to what ejn63 has said, the 9-cell battery has an extended piece that runs along the back edge of the system and extends further from the bottom. Because of this design, the system actually rests on the battery and is at a steeper incline than when the 6-cell battery is installed.
If you are from the USA, you may contact our Dell Spare Parts sales team @ 1-800-372-3355 to order a compatible battery.
Do let us know if you have any further questions.