Time codes 3:06, 37:07, 43:57, 43:36 (note on the eCVT naming), and 44:17.
[0] https://global.toyota/en/newsroom/corporate/27512455.html
Having worked in the field I've been of that opinion for 15 years or more. Two motors and a planetary gear are simpler than a regular transmission. More efficient also, and more reliable. The inverter and small battery may add some cost, but the MPG improvement is more than worth it.
Hybrids are an awesome improvement over plain old ICE, but they tend to get an unnecessary price premium due to their advantages.
Trains don't do the above in large parts because the gears needed either wouldn't fit in the allowed space. (we may not be able to make them large enough either - that problem is solvable but may not be worth it)
The place where they fall behind is at steady state on the highway -- but all of the series hybrid systems on the road have a solution for this problem too! They typically have clutch that engages a one-speed direct drive from the engine to the wheels. This skips the double-conversion losses at highway cruising. Then if you give it some gas to accelerate, the clutch disengages and you go back to full double-conversion again.
Efficiency seems to match or exceed conventional hybrids in city driving, and only slightly less efficient for highway driving. And people like the instant torque and the smooth “EV like” driving feel.
I agree in principal that there's efficiency to be gained by minimizing conversion losses, but Honda may be clawing that back with larger and more efficient motor-generators that only package well because no planetary gear set is required to connect everything.
* Honda hybrids do have either one or two clutches to mechanically connect the engine to the wheels at fixed ratios for highway cruising, but their city EPA numbers are still very competitive.
"In that concept, the rotary engine functions as a generator to produce electricity for the battery and electric motor, rather than mechanically driving the wheels."
Excited to see if this becomes a reality
more: https://uscarcover.com/blog/2026-mazda-rx9-review-rotary-is-...
The engine doesn’t run at a constant speed though, it responds to the amount of electrical power needed.
However, in the USA, in order to get EV status, it was nerfed where it was only allowed to use its engine to charge the battery once you went below a 30% state of charge, and next to that, the fuel capacity was electronically limited.
A neighbor of mine had one, and the engine couldn't keep up with charging the battery to move the car on the freeway + running the AC, because it wasn't powerful enough.
In the EU version, this wasn't a problem, because you could set up the motor to run to maintain a charge (instead of only allowing it to run below 30%).
Edit: 30% state of charge, not 10%.
https://expeditionportal.com/the-extended-range-ev-influx-is...
The latter was sold in the UK/EU and was on the market for two years only.
The Chevy Volt was one and the current Honda CRV is another. Both of them work mainly by the gas engine driving one of the electric motors as a generator while the other motor drives the vehicle. They have a simple eCVT transmission. However, both vehicles have a mode where they directly engage the engine to the transmission at highway speed cruising because that is more efficient.
Nissan has a series hybrid system that they have used in the Note that is only the series hybrid without the direct connect mode. That saves some money.
It took a while and several explanations for it to completely click for me. The e-cvt mechanism does seem to be quite clever and simpler (at least mechanically).
This does not appear to be a packaging issue, as the late 2000s LS 600h had a V8 with rear-wheel drive (and then AWD) with an “eCVT” in a “conventional” longitudinal package.
I think the most important question is whether the system requires a regular automatic/manual transmission or forgoes one entirely. The Toyota planetary gear system forgoes one, as does the modern Honda and Nissan approaches. Not having a transmission in the traditional sense saves so much complexity that the overall system is net simpler imo even with the additional complexity from having a motor and engine.
Then there are systems that have a full automatic drivetrain and some extra clutches to couple to a motor-generator. And there's even systems with an electronically controlled manual transmission instead. Those systems are going to be incredibly complex and fragile.
