Yes. The battery lasts for 2 years. It is really easy to change and BlueJay uses coin cell battery which is widely available.
Bluetooth Smart (sometimes called Bluetooth 4 or Bluetooth Low Energy) is new wireless communication technology which allows get bigger range and security than in standard Bluetooth with much reduced power consumption at the same time.
You can track your car from up to 80m, depending on the environment.
Don't see the answer to your question? Ask the project creator directly.