EVDRIVER wrote:On hills it's a killer.
I understand that you're against weight - and agree. And yet, if we take a Leaf that can run 100 miles and THEN add 300 lbs, there's going to be a performance hit. But if we take a Leaf at it's weight and 100 mile range, and put it along side the Focus and it's 100 mile range, then the weights don't seem that significant at that point.
Sure - more weight means more structure and more battery and more power and larger motor, I get the gist of the design spiral and the desire to 'add lightness'. But is it really accurate to take two fully developed cars with apparently similar performance and single out weight?
What am I missing, EVD?
This is a classic trap, comparing a heavy EV to a very heavy one. Besides aerodynamics weight is a HUGE factor in efficiency. Anyone wonder why all the major auto makers are racing to cut weight to make the future EPA numbers? In an EV this makes even more of an impact. If you drive in an EV with a respectable weight of say 2700 lbs and watch actual kw usage and then add weight in 100 lb increments under the same conditions you will become very aware of the impact in efficiency and in your foot. Put a hill in the mix and is exponential. This and aerodynamics is what it is all about in an proper Ev design. The pack is a separate issue on its own, just look at why so many converters use the lowest weight car available, why Tesla builds the way it does.
An EV is FAR more sensitive to fluctuations in efficiency than an ICE because of the available energy storage density between gas and our present battery tech. This is only evident when people go up hills or see detailed consumption data while driving and when they see the difference in weight variables. The mods people made to cars for aero gains make even greater strides on an EV. Even the viscosity of the gear oil in an EV can make an impact on range, also the cut on the gears. The leaf gears are set for noise and compromise on efficiency, these things do make a difference particularly when added together. If you own a compact car, add 300 lbs and see how it does up hills and how the economy changes while driving the same on hills and on the city, the rules don't change because the car is already heavy.