drees wrote:There one important performance spec that also degrades along with the battery: Efficiency. Without regen, you lose significant efficiency whenever you have to slow for a stop, unless you are extra careful and give yourself plenty of room to slow down.
On my way down the mountain today, I ran the cabin heater at a continuous 3 kW or so. Owing to the fact that there was scarcely any regen available (4 temperature bars and less than 80% charge), the LEAF reached the bottom of the 4900' descent with less charge than I started with
. Even at about 50% SOC (six battery bars) near the base of the mountain, the available regen was zero or close to it. I had to make two long stops to cool the brakes, thus doubling the duration of the drive. Even still, the brakes smelled and some shuddering occurred.
drees wrote:I really wonder how the EPA efficiency specs compare with a new battery compared to an old one, and if the EPA cares that cars within their warranty period can lose a significant amount of efficiency.
I doubt the EPA cares a great deal. Gasoline cars also lose efficiency with time, though not this dramatically.
The dealer representative who took my key fob did note on the paperwork that the car can't be driven down the mountain (that is, not in any "normal" fashion) due to bad regenerative braking. He seemed attentive to my concerns and was sympathetic when I explained that this is a safety issue and that regenerative braking is supported by the lithium-ion battery which remains under warranty for defects. We'll see what the LEAF tech says.