Submitted by TimHuey on March 27, 2013
As I reach for the charge cord more frequently for my cell phone every passing day I worry about the implications for my future Model S. I know the battery capacity will diminish every year. Even TESLA puts a NEW battery (<1y/o & <25k miles)as one of their prerequisites for getting the stated mileage. We have had enough TESLA battery powered cars out for a sufficient amount of time to see some data start to come in. At least we should be able to see if the degradation is linear or curved over time.
My cell phone battery's life span is about a year. At that point its down about 2/3 of what it was. I would think the same would be said for a car battery. If 260 miles was what you bought your car for and all of a sudden you could only drive 156 miles, you would probably have major problems doing the things you bought the car for. Or at a the very least, a major reworking of how you get them done. So if my Model S's battery drops below 2/3 of the stated range I would be looking for a new battery. When is that 2/3's number going to be hit?
I understand that supercharging has an effect. Lets assume 2 super charges a month to full capacity. The rest of the charges would be thru twin charging 240volt 100 amp circuits. Driving on average 15k miles a year in south Florida.
Any ideas on battery life degradation projections?