myLexus007

Anyone heard of anything about the new Lexus' Next Generation Hybrid - Multi Stage Hybrid? It's supposed to be introduced to the 2018 LC500h. The quote from Lexus is the new system will be "enhanced driving pleasure, more performance, and greater efficiency", but I wonder when/if it will triggered down to lower models like ES/GS/CT etc.

I supposed the 2019 ESh/GSh will be equipped with it?

chromedome

Not sure what multi stage hybrid means. The cheaper Lexus and Toyota hybrids have a single planetary gear transmission with 2 motors and the engine; the GS450h and LS600h have two planetary gear systems piggybacked together to handle more torque and to get more efficiency at higher speeds. Maybe the LC500h will use the latter system.

Then again, the new Prius adds a one-way clutch like the Volt to its planet gears for higher efficiency and a more direct feel. Maybe Lexus will add that component too. I'm thinking they should make the LC500h a plugin hybrid to go head-on against the i8 since both play in the same price bracket.

jollick

Check out this article https://lexusenthusiast.com/2016/02/...-hybrid-coupe/

chromedome

Thanks for the link. It looks like a variant of the GS450h system but with an automatic transmission (dual clutch? torque converter?) hooked up to the planetary gearset. To the ring gear that's usually hooked up to MG2?

You'd get a more direct feel because the auto box ultimately drives the wheels, whereas a typical Toyota hybrid has no set gear ratios and manual mode just means setting rpm points. I'm wondering how efficient this two stage system is compared to connecting the electric motor directly to a dual clutch box like on the i8, or running the engine without a transmission like on the Accord Hybrid.

350 hp total system power also isn't a lot. It's similar to the GS450h or RX450h when this car should be putting out 400-500 hp total.

bartman44

Would like to see Lexus incorporate the battery into normal accelerations if the battery is fully or near-fully charged. If this is automatically done, accelerations in ECO mode will be peppier. It often seems like charged batteries are not being used unless the speed is below 40 mph. What I do now is use Sport mode for about 3-5 sec from a standing stop and then revert to ECO mode. My mileage has averaged 44.9 since I bought the 2014 ES 14,000 miles ago. Since I started doing this manual mode switching about 4 months ago, it is quite common to finish a tankfull close to 47 mpg...and that's with ethanol gas!

chromedome

That's remarkable. I've been using Eco mode during my commute and doing pulse and glide - I start off on engine power at 2000 rpm to reach my target speed before gliding on battery. I'm only getting 45 mpg and this is with pure gasoline without any ethanol in it.

What's your rpm when accelerating in Sport mode? After switching to Eco, do you lift off the throttle and glide on battery? And what's your target speed?

I've seen 60+ mpg on a slow, steady drive on rural roads with cruise control enabled. I can't get any higher with manual pulse and glide.

bartman44

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I keep RPM below 2500 in Sport mode while accelerating. I observed the battery use in Sport mode, and the battery use seems to drop out when RPM gets much higher. That negates the goal of keeping the battery more involved. I drive normally thereafter, although taking advantage of "freewheeling" at 1000 RPMs occasionally as traffic conditions allow.

Vladi

Is the case of two planetary system limited only to GS450h and LS600h or GS/IS300h belong in that category as well?

chromedome

Only the GS450h and LS600h have the dual planetary gearset transmission. The 300h variants of the IS, ES, GS and NX share the same hybrid drivetrain with the Camry and Avalon hybrids, with a 2.5 liter engine and a single planetary gearset. It's funny because the second gearset is supposed to give a more direct feel but reviewers still complain the GS450h has the typical hybrid rubberband feel.

As for the battery not being used at higher speeds, it's not an efficient way to run the car given the small battery pack. If you have a full charge, the battery does give a boost during acceleration up to 60 mph. The engine also has to run at higher speeds to keep MG1 from spinning backwards too fast.