In January I got my CPO 2013 Model S. I recently found out about the A/B batteries and the limited SC charging rate on the older A batteries. With the helpful info I went underneath the car to check the battery stick only to find out it was gone. I had been there, but probably had been worn off from use. Is there any other way to determine if I have an A battery or B battery? I want to know for time planning since the A battery will take longer to supercharge.