You could easily get 75kW(100hp) out of a 10kWh battery, it's not even 'just theoretical'. The 8.8 kWh unit from the Prims already makes 70kW(93hp). PHV batteries are usually rated at 5-10C, which means the (numerical value of) power is 5-10 times the capacity. At 7.5C a battery will completely discharge in 8 minutes (60/7.5), but all ratings are 'peak values', the definition of which varies. Usually it's a 15-second burst or 30-second burst scenario (to simulate an overtake maneuver, for example). Most of the time the vehicle will be cruising at 80-120kph and only requests 15-40kW of power, but manufacturers rarely disclose 'sustained cruising power' for batteries.
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You could easily get 75kW(100hp) out of a 10kWh battery, it's not even 'just theoretical'. The 8.8 kWh unit from the Prims already makes 70kW(93hp). PHV batteries are usually rated at 5-10C, which means the (numerical value of) power is 5-10 times the capacity. At 7.5C a battery will completely discharge in 8 minutes (60/7.5), but all ratings are 'peak values', the definition of which varies. Usually it's a 15-second burst or 30-second burst scenario (to simulate an overtake maneuver, for example). Most of the time the vehicle will be cruising at 80-120kph and only requests 15-40kW of power, but manufacturers rarely disclose 'sustained cruising power' for batteries.
bogglo
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am curious
If they decided on this, they already future proofed the system... new 300h's main motor still has 118hp.
Question is if they believe this to be right action to take, not if it is possible - it certainly is, just the question if they decide to do it or not.
indeed, and recharging is question of mpg, nothing else... they can simply recharge with engine more to get back some of the power, but yes this will decrease MPG substantially... but will give you really a sport hybrid.
Right now every hybrid that Toyota has only one mission - to increase mpg. Only with recently introduced UX and ES, they started mentioning more about sports mode that gives more battery power. This was possible before as well but it would decrease mpg so they did not care about it.
TheNerdyPotato
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You're right. I don't know what I was thinking when I wrote that. Maybe the range limitations that spwolf mentioned. I had just got back from a week vacation and my brain was (and still is) frazzled.
german phevs, while really bad in general, have mode that lets engine recharge battery aggressively.... so it could actually work pretty well in HSD, but again question is what about getting pretty bad mpg since engine would be running at higher rpms all the time to recharge battery faster.
and it in all my reviews of phev's reading, this has been mentioned 1 or 2 times... and it is a major problem but i guess if they dont care about Porsche Phev losing half of ev-power after some aggressive driving, would they care about Toyota/Lexus?
new V8 in upcoming Tundra?
F1 Silver Arrows
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Because they don't understand the concept of things working to perfection. They're so blinded by the fact that while at times they may push out dynamically superior cars, they can't manage to hold a damn candle to what Lexus (and to a greater extent Toyota) is able to do. The only exception to this is Porsche, even then, Toyota are much more ahead of them in terms of hybrid technology, and also the fact that they're taking great care of how the battery will live during its lifetime, so they make everything about it toned down and understressed, because for most buyers, they want something with no frills. The only issue to this is the god-awful CVT that's mated to the engine, but if it had the 8-speed automatic or even the multistage-hybrid system transmission, it would do the car wonders in terms of performance, also having pretty good fuel economy at the same time. It's reached to that point for me that CVT's in this day and age are quite dangerously slow. Would you sacrifice five, or maybe if all hell goes loose, ten miles per gallon (I know it doesn't even make that much of a difference, but I'm trying to make a point here), even though with a CVT is horrendously slow, and can really hurt you in terms of performance? Sometimes performance is necessary, because that allows the driver to do crucial things when on the road, like passing, overtaking, or launching off the line in important situations. I also feel like it won't also make a huge difference in fuel economy either. This is the only thing that I feel the Germans are edging out the Japanese. Nothing else.
This was mentioned and TMCs hybrid reviews, battery lifetime, replacement cost etc... funny how now this problem does not exist with German hybrids.
I have to say I do not dislike CVT on hybrids.
I don't think latest THS allows full parallel hybrid operation, so some of MG2's power will always come from MG1, which is taken from the engine. The bigger hybrid systems are indeed sized (88kW for 2.5 and 80kW for 2.0) to allow EV operation without assist from MG1, so they could in theory get more power from the bigger battery in HV mode. There are just too many variables in a serial-parallel hybrid that analyzing the power balance is almost impossible for non-experts so I'm not making any more predictions.
Remember, serial-parallel hybrid allows regen and electric drive at the same time (ICE->MG1->MG2+HVB). A more aggressive regen strategy will not impact MPG too much, because it is also shifting the engine to a more efficient operating point. It means missing out on some kinetic energy recovery opportunities since the battery is likely to have a higher SoC, but KERS only accounts for about 20% of MPG gains on serial-parallel hybrids.
On a parallel hybrid, you are just wasting fuel to charge the batteries, which is incredibly inefficient (my BYD Qin, for example, requires 10kW of power from ICE to recharge the battery at 5kW). Parallel hybrids rely more on KERS for regen, and their load-shifting is not nearly as efficient. This is why those German PHEVs are basically useless when the traction battery runs out. In that situation the hybrid system just becomes dead weight. Luckily for them, the battery has a lot of capacity, so unless the user drivers like a hooligan it's unlikely to run out.
Here's a quick lecture on how input-split hybrids work. The engine is not mated to a CVT. In fact THS does not even have a transmission: it is the transmission. The planetary-gear system is what decouples engine speed from wheel speed. This is why it can operate like a CVT. This is also why it is the best: super simple, super efficient, and, believe it or not, cheaper than a parallel hybrid. After all, a parallel hybrid still needs a costly automatic transmission.
Traditional CVTs are slow off the line because they are designed to operate at highway speeds. It is possible to optimize CVT for acceleration but it just means losing fuel efficiency during cruising. That problem is easily solved by adding a launch gear to the CVT, which is what Toyota did recently. But that's irrelevant in a hybrid, because MG2 provides enormous amount of torque at start. But just like any electrified vehicle, the performance of hybrids is mostly determined by the software, not the mechanical components themselves.
I will again bring the China-only Corolla/Levin hybrids to this discussion, because honestly TMEC Suzhou did the best job at making hybrids that are not annoying to drive. The Corolla hybrid is tuned for two scenarios: 0-50kph and 30-60kph acceleration which are the most common on chinese roads (starting from a green light and accelerating onto a highway ramp). At these speeds the hybrid system employs electric boost very aggressively, almost ramping up to maximum output instantly, unlike the Prius that just bogs even at WOT. To compensate for that, they also employ more aggressive regen strategies. Their market campaign repeatedly show the Corolla outrunning the BMW 320i or the Audi A4 TFSI. The end result is very positive; people recognize hybrids as not only more fuel efficient but also very fast.
An overly conservative software is what gave the Prius a terrible reputation. To preserve battery and maximize MPG, the hybrid system is programmed to, well, do nothing. The Corolla hybrid uses an identical hybrid system found on the Gen 4 Prius, but the two couldn't be further apart in terms of driving quality. The fuel economy for the Prius and the Corolla hybrid is 4.3L/100km and 4.7L/100km respectively. That's a 9% difference, but the Prius also had tons of aerodynamic and weight-saving tricks so I would say the actual advantage is less than 5%.
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To continue with the discussion, I would like to point out that the single biggest problem with THS right now is the battery. It's too small, too weak, and it's NiMH. It's a consensus in the automotive industry that other components of the THS are at least two years ahead of competition, but it could have more potential if not for the outdated battery tech.
It's almost a miracle the Prius can get over 50MPG with a 1.3kWh (NiMH)/1.0kWh (Li-ion) battery pack, of which only 40% of the capacity is actually usable to preserve the battery. This means at anytime, the hybrid system only gets 1.8MJ of energy reservoir to work with. It's like managing your finances with a very small bank account. Therefore it needs to very carefully balance boost and regen. Early generations of Prius use a very primitive system based completely on throttle input, which means MPG is heavily dependent on driving style. It is well known Prius hypermilers are constantly monitoring battery SoC and driving in a manner to not waste any regen opportunity. The latest Gen 5 has some predictive measures based on machine learning, but it still needs to constantly predict when the energy is needed. For example, it may not know a driver will be climbing a long gradient and recharge the battery accordingly.
Having a bigger battery brings a ton of benefits. Let's say if the Prius is equipped with a battery half the size of the Prime's, i.e. a 4.4 kWh 35kW Li-ion unit (compared to the 1.0kWh 20kW Li-ion unit). Such a battery would only weigh 20-25kg more.
>>The battery can discharge much deeper, since it needs to discharge fewer cycles for a given energy consumption compared to a smaller one. The 4.4kWh unit could make 50% of its SoC available and that will be 8MJ of energy reservoir.
>>Having an energy reservoir over four times as large gives the car much more flexibility without much prediction of what the driver is going to do next. For example, it could simply brute force a gradient with the extra energy it stores. Again, the bank account analogy applies here. You are much more flexible with when and how much to save up or spend if you have a bigger account.
>>Since the battery has more power, the car can operate in EV mode more frequently and at higher speeds.
>>The car will be more powerful in general, that's pretty straightforward.
This is why I said the Prime is what the Prius needs to be in the first place. It's very encouraging to hear that the Prime's battery pack is now marginally more expensive than the NiMH unit on the regular Prius. I think for the next generation they need to design a modular battery system for regular hybrids and plug-ins, for example a 5kWh 40kW 'block' that can be combined into different configurations.
It's almost a miracle the Prius can get over 50MPG with a 1.3kWh (NiMH)/1.0kWh (Li-ion) battery pack, of which only 40% of the capacity is actually usable to preserve the battery. This means at anytime, the hybrid system only gets 1.8MJ of energy reservoir to work with. It's like managing your finances with a very small bank account. Therefore it needs to very carefully balance boost and regen. Early generations of Prius use a very primitive system based completely on throttle input, which means MPG is heavily dependent on driving style. It is well known Prius hypermilers are constantly monitoring battery SoC and driving in a manner to not waste any regen opportunity. The latest Gen 5 has some predictive measures based on machine learning, but it still needs to constantly predict when the energy is needed. For example, it may not know a driver will be climbing a long gradient and recharge the battery accordingly.
Having a bigger battery brings a ton of benefits. Let's say if the Prius is equipped with a battery half the size of the Prime's, i.e. a 4.4 kWh 35kW Li-ion unit (compared to the 1.0kWh 20kW Li-ion unit). Such a battery would only weigh 20-25kg more.
>>The battery can discharge much deeper, since it needs to discharge fewer cycles for a given energy consumption compared to a smaller one. The 4.4kWh unit could make 50% of its SoC available and that will be 8MJ of energy reservoir.
>>Having an energy reservoir over four times as large gives the car much more flexibility without much prediction of what the driver is going to do next. For example, it could simply brute force a gradient with the extra energy it stores. Again, the bank account analogy applies here. You are much more flexible with when and how much to save up or spend if you have a bigger account.
>>Since the battery has more power, the car can operate in EV mode more frequently and at higher speeds.
>>The car will be more powerful in general, that's pretty straightforward.
This is why I said the Prime is what the Prius needs to be in the first place. It's very encouraging to hear that the Prime's battery pack is now marginally more expensive than the NiMH unit on the regular Prius. I think for the next generation they need to design a modular battery system for regular hybrids and plug-ins, for example a 5kWh 40kW 'block' that can be combined into different configurations.
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Would TMCs hybrid system make sense for duty vehicles, paired to a diesel engine? The next Land Cruiser might not have such tech, because usually the Land Cruiser only adopts proven tech, but for example the next Prado? I am somehow surprised there are yet no (many) hybrid duty vehicles, the hybrid (non-plugin which still does not convince me) has proven itself.
TheNerdyPotato
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https://www.greencarreports.com/news/1088464_toyotas-largest-heaviest-hybrid-hino-195h-truck
https://www.greenfleetmagazine.com/125206/hybrid-hino-cabover-gets-14-mpg-for-plumbing-fleet
Apparently, they do make some sense. Maybe not exactly what you were looking for, but if tow trucks and moving vans can get better mileage, I'm not complaining.
To circle back to Toyota/Lexus' state of engines: I've said it before and I'll say it again, this company's poor engine development is one of the PRIMARY reasons Lexus' higher echelon sedans and coupes sell so damn poorly. People buy these cars not to just shuttle people around (that's what SUVs are for), but for a performance element that Lexus just lacks and flat-out lies about to compensate.
Everything from the 4 cylinder up to the 8 cylinder are just piss-poor and they don't perform nearly as well as the competitors'. In fact, competitor's 4 cylinders typically out perform Lexus' 6 cylinders in REAL-WORLD testing.
That's why BMW, Audi and MB's 4 Cylinders are so popular: they actually perform well, trouncing even Lexus' ubiquitous V6.
Toyota just doesn't know how to or refuses to develop a decent engine. The complete lack of effort in the Supra (they didn't even try) and the poor-performing 3.5L V6 tt (what were they smoking when they published the performance numbers?) says all that needs to be said.
Remember this and watch when they release whatever engines. Pay special attention to what Lexus says these engines are capable of versus what everyone else tests them to and laugh...
Everything from the 4 cylinder up to the 8 cylinder are just piss-poor and they don't perform nearly as well as the competitors'. In fact, competitor's 4 cylinders typically out perform Lexus' 6 cylinders in REAL-WORLD testing.
That's why BMW, Audi and MB's 4 Cylinders are so popular: they actually perform well, trouncing even Lexus' ubiquitous V6.
Toyota just doesn't know how to or refuses to develop a decent engine. The complete lack of effort in the Supra (they didn't even try) and the poor-performing 3.5L V6 tt (what were they smoking when they published the performance numbers?) says all that needs to be said.
Remember this and watch when they release whatever engines. Pay special attention to what Lexus says these engines are capable of versus what everyone else tests them to and laugh...
problem here is the price + it is still significantly dirtier than petrol hybrids...
but it would certainly be sweet in Prado.
I won't even try to argue with you on who makes the best engines in the world, because your comment is mostly untrue.
The winner is obviously Mazda, the second BMW, but TMC should be a pretty close third.
Wake me up when Audi reaches 40% thermal efficiency.
Who cares about “thermal efficiency.”
You think the average driver—especially one that can afford these cars—gives a cent-pence to something that no one understands outside the Society of Automotive Engineers?
No.
I’ll be sure to tell the salesman that I’m not going to buy the Audi because it has less thermal efficiency than the Lexus...
You think the average driver—especially one that can afford these cars—gives a cent-pence to something that no one understands outside the Society of Automotive Engineers?
No.
I’ll be sure to tell the salesman that I’m not going to buy the Audi because it has less thermal efficiency than the Lexus...
F1 Silver Arrows
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How is it even possible that you can be this dense? Seems like I spotted the one who hasn't had the car-buying experience before.
You don't seem to understand how important "thermal efficiency" is nowadays. It seems like if I tell you within terms of horsepower, then you'll be able to understand, because you probably don't comprehend anything further than that (no offense). Hey kiddo. Thermal efficiency is not only a huge benefit in terms of fuel efficiency, but horsepower too. That's how the new four cylinder that's in the 2018 Camry gained around 30 horsepower more than the 2017 Camry. It's because of "thermal efficiency".
That isn't enough for you? Absolute mad and modern race cars that grace this earth chase high levels of thermal efficiency. That's how they perform so well. If you manage to hit that sweet spot and beyond, that's what will give you the edge over your fellow competitors. Formula 1 and the World Endurance Championship are both examples of high-profile series that chase thermal efficiency (I can still list more racing series if you like to prove you wrong).
Think twice about what the hell you're saying. "Who cares about thermal efficiency"? The world does. It is one point within engineering and technology that is driving us forward among other things (and even then thermal efficiency is NOT the only big thing out there). Give me a break. You're welcome for the small engineering lesson by the way.
I appreciate you putting your thoughts in the forum, but your ignorance is shameful.
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Ian Schmidt
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Have you actually driven an LS500 with the TTV6? It's a *substantial* improvement over the outgoing V8 in terms of always-available power, and it gets better MPG doing it. That engine and the handling from the GA-L suspension put a smile on my face every time I drive the thing.
If what was on paper covered the experience of driving cars, we wouldn't need cars.