If a lithium ion pack has 300-500 full discharge cycles or let's say 1000 or more partial discharge cycles, would you really compromise your $15,000 battery pack by draining it back to the grid on a regular basis? What about if you are a single car family and your wife develops a migraine and needs you to go to the store at midnight for medicine? Sorry, you will have to wait while I recharge the car. I sold power back to the grid.
I know I am coming off as being totally against electric power but I am not. I am simply a pragmatist. I have personal experience with both lithium ion and lithium polymer technology. They are dangerous and must be respected.
Ever heard of Horlacher? I was bitten by the electric bug way back in the 80s.
http://www.horlacher.com/products_se...ment/index.htm