Overview:
This week is a prelude to my upcoming review of the Kia Soul EV for 2015.
Merkel Weiss gives us an automotive engineer’s take on the subject of Electric Power for the Automobile.
High Performance 21st Century Design Directions by Merkel Weiss 1-1-15
Now that we’re permanently entrenched in the era of the return of electric drive in automobiles, it’s clear that battery design is going to be the new engineering Holy Grail. The energy density is the Kilowatts (KW) of stored energy per Kilogram (Kg) unit of battery weight. As we push for more and more energy density, the battery materials are necessarily more and more exotic. Currently we’re getting comfortable with Lithium polymer batteries, apparently without notice that several Fisker Karma and Tesla Model S sedans have burned down from battery pack fires. I’m confident that we’ll eventually get past this hiccup in battery production quality. We still have a significant learning curve in order to get where we want to be, on some level on a par with gasoline model vehicle range of about 300-400 miles per refill. These new battery materials promise to be more and more volatile.
One particular promising direction appears to be super-capacitors. These are electrical energy storage devices much like a battery except that where batteries generally prefer to release their stored energy slowly and then recharge slowly, super-capacitors like to release the stored energy quickly. This makes it a pretty good auxiliary power unit for launch of an electric drive vehicle. Although they are far from perfected at this time, the technology appears promising in the near future. Since electric motors have full torque at very low speed, they’re only limited by how much electrical energy can be rapidly dumped from storage. This is in direct contrast to rotating engines where the torque delivery is limited to being proportional to the crankshaft rpm.
This coming year in Formula One Racing brings some new innovative changes that will have the effect of increased efficiency on street cars in a few short years. The hybrid drive system is aided by a turbocharger which recovers heat and flow energy from the engine exhaust and converts it not only to an intake charge pressure boost (as usual) but also to electrical energy, stored in the battery pack. For this purpose, the turbo has its own electric motor/generator which could also serve to completely eliminate turbo lag.
These are several examples of how electronic engine optimization is stepping up. It’s no longer a simple management system, but now an entire integrated hybrid drive system which recovers kinetic (motion) energy from wherever it can be found, converts it to electrical energy, stores it for future use, and then delivers it back to the drive system.
Transmissions will have many more gears in the future, perhaps as many as ten. CVTs (continuously variable transmissions) will be common and the days of old geezers shifting gears will be gone forever, replaced by ever more efficient gear changes that are microseconds in length and unnoticeable in character. Just a note here: I love to shift gears, and I love the increased durability of a manual gearbox. I especially like the way I can control the rate of power takeup, a feature not possible on any self-shifting
box.
Steering columns between the front wheels and the steering wheel will be gone soon. They’ve always been extra weight and a packaging problem, not to mention a serious crash liability for manufacturers. The steering wheel will be backed by a rotary servo which in turn will translate motion to the electric servo on the front rack and pinion steering. Who needs actual road feel anyway? It’s only a distraction. The first car to have this steer-by-wire feature, the Infiniti G50 is already on the road. Infiniti calls it DAS, Direct Active Steering.
Shortly, brake systems will delete the mechanical and hydraulic components altogether, and the ABS systems will simply do full duty in their place. The new system will be cheaper, lighter and more efficient as well.
Repair of all these on-board electronic devices will take a new kind of automotive repair technician, one that is not yet in place. We can only hope that he is more competent than the previous generation. Things will certainly be more complex, more expensive and more disposable. These are my best projections. The only thing that I can say for sure is that drivers don’t need complex systems to replace simple ones. It just seems to be the direction that things are going.