Toyota faces obstacles in developing hybrid Tundra

Toyota Motor Corp. is working on a hybrid version of its next-generation Tundra pickup. Toyota is conducting an engineering feasibility study to determine whether a Tundra hybrid can meet customer requirements. Toyota will redesign the Tundra in early 2007. Hybrids use gasoline engines and electric engines to power the wheels.

A hybrid work truck presents engineering challenges not present in standard cars, said Dave Hermance

Hybrid battery packs provide excellent low-end torque which is good for quick-effort heavy lifting. But many truck owners require their vehicles to tow or haul heavy loads over long distances. Hybrid battery power is nearly useless in that aspect. As a result, a pickup cannot scrimp on engine displacement without sacrificing towing performance. That will hurt fuel economy, the main benefit of a hybrid. Long-distance towing stresses the durability of a hybrid system. Toyota plans to sell 300,000 hybrid vehicles worldwide in 2006 and 1 million by 2010.



Source: www.autonews.com

[Bakemono]

Toyota will figure it out. I think they will have to tweak the speed at which the gas motor kicks in (perhaps some kind of load sensor), but they will figure it out.
The media was skeptical of the Prius at first, saying that it would never catch on, and they are now eating their words. Why would the Tundra hybrid be any different?
Cap'n

[Tideland Prius]

Hmm. Good point. All I can think of is a larger battery pack since a truck will have more space for it. The Highlander Hybrid and RX400h already use a newer battery pack. It's thinner and more powerful than the one in the current generation Prius.

Another possible solution is a more powerful electric motor. This way, the engine can use less fuel by outputting less power because the power that's going to the electric motor is being amplified by a larger margin. (Maybe the engineers in this forum can check if I'm making any sense lol).

[91MR2quickNA]

A good solution would be to run the hybrid system in parallel with the engine during towing, like through a switch. The motors would have to sustain regular use, and heavy duty use though. If Toyota develops a new electric motor that can rev in parallel to the engine (like an alternator) and run for hundreds of thousands of hours, then maybe Toyota would have something.

I think they're just going to develop a diesel for now though. Hino has hybrid diesels, so maybe they can use some of that technology.

[CACressida]

I was thinking that there would be a trailer mode, when towing, the hybrid would shut off the engine durring stops, shut the engine off when cruising under 40mph, and help accelerate uphills, or even from dead stops. That would do a big difference in mpg. The engine would put in less effort and that means lesser fuel consumption. After you throw your trailer away, trailer mode off, and you have normal hybrid operations like the Prius.

[situman]

I think what the article is saying is that with towing vehicles weight becomes an issue for the electric motors. Two or so tiny little motors will have to tow an enormous amount of weight if the engine is shut off during stop and go traffic. Remember, the heaviest vehicle is the RX400h. But with the Tundra, it would have to sometimes haul up to 11k pounds (vehicle+its max towing capacity). That's more than 2.5 times the weight over a RX. Durability will definitely become an issue.

[Tideland Prius]

I think you mean the battery? The motors shouldn't have a problem cause either way, it'll receive power either from the battery, engine or both. The engine powers the wheels "directly" and can also send power to the motor which then decides whether it's needed to power the wheels or to recharge the battery.

Hybrid battery packs are the problem Toyota is trying to solve. They are only good for quick-effort heavy lifting, but Toyota is trying to find a way so they would be good for heavy loads over long distances that many truck owners want without hurting the fuel economy that the hybrid is made for. I think they will be able to find a way, but at least they will have the 300+hp Tundra before the hybrid. This should give them some time.