My Kia Niro EV only has one "gear". My Chevy Volt before that only had 1 "gear" (but a much more complex hybrid system of planetary gears and direct drive components). I would love to see more EV's get a second "high speed" gear put in them, but my guess is that the engineers have tried this and have not found the efficiency to increase at high speeds vs the single "gear".
EV's in real life have many upsides to them but there are a couple downsides: 1) High speed efficiency needs to get better and 2) cold weather efficiency needs to get better. In the summer I can get over 6 miles/kWh at speeds below 40mph. In gasoline terms, that like getting 130-140 mpg. At 70mph on the highway, it drops to about 4 miles/kWh. Thats a 33% efficiency loss which, frankly, sucks. If a second gear, ie. a "High Speed" gear, could net only a 15-20% loss, that would greatly increase your drivable range at highway speeds. Most normal EV cars could see a 50-80 mile range increase if that type of efficiency gain could be found. Low speed driving would be unaffected. But my guess is that the efficiency losses are more from wind resistance and general aerodynamic drag than the motor spinning at high speeds. Cold weather efficiency (below 40* Fahrenheit) drops the efficiency another ~25%, and that is without using any heat in the car, expect ~30% efficiency loss if you use heat. So that needs to get worked on as well. Fortunately, we are still in the early days of EV cars and it will only get better as more time, testing and technology comes in to the fray.
First, I agree with you, EVs are still evolving and have a little ways to go before they're ideal for EVERY use case. But to address your two main points:
1. High Speed Efficiency -- The thing is, high speed efficiency literally can't get better. EV motors are already almost 100% efficient at all RPMs, to the point where wind resistance is really the only factor affecting efficiency. The reason they SEEM inefficient at high speeds is because gas engines are extremely inefficient at low speeds, and slightly less inefficient at high speeds, so we're used to seeing better mileage at high speeds than at lower speeds. But EVs are equally efficient (near 100%) at all speeds / RPMs, so even with extremely aerodynamic designs, this guarantees (non-linear) efficiency loss as speed increases due almost entirely to wind resistance. In gas cars, wind resistance is a much smaller piece of the efficiency pie. Because so much of the power released by the gasoline combustion is already being consumed as noise, heat, internal machinery, and the effects of a relatively narrow power band compared to EVs, the added inefficiency of wind resistance is just one of a large number of inefficiencies for a gas car, rather than almost the only factor like an EV.
A transmission does nothing for an EV's high-speed efficiency, since electric motors are (roughly) equally efficient at all RPMs. All it does is allow a higher top speed if the motor happens to be running out of usable RPMs. The added weight, complexity, and drivetrain drag definitely wouldn't have a positive effect on high speed efficiency. Its only use is higher top speed, at the
expense of efficiency. Honestly, using a transmission simply doesn't make sense for a motor that has equal torque and nearly identical efficiency across its entire RPM range. Picking an appropriate final drive ratio is the real answer that I think all EV makers are going to come to, even for high-performance models. The Model S gets to 212mph in first gear. No tranny needed*. But back to the point -- in the end, it's the wind that affects EV range at high speeds, not the high RPMs.
2. Cold Weather Efficiency: Tesla greatly improved cold weather efficiency by switching from a traditional resistance heater to a heat pump system in their newer models, and uses software to strategically keep the battery warm. I think the cold weather issue is overblown anyway ... practically all new cars in Norway are EVs, and I think it gets more than a bit chilly over there. I mean you're not wrong, range is definitely reduced in cold weather. But it's not a dealbreaker IMO or apparently in Norway's opinion either.
* the motors that drive the rear wheels have a different final drive ratio than the motor that drives the front wheels ... is that technically "two gears" even though they're both usually active at the same time? The software shifts the front/rear balance dynamically for various power / efficiency / handling reasons but i don't know the details.
