Feb 8, 2007 (From the CalCars-News archive)
The next model of the Highlander Hybrid will give drivers the option to push a button upon starting up and thereby defer the start of the internal combustion engine, which otherwise happens automatically several seconds later. Driving in "Electric Vehicle Mode" is very handy if you want to move your car across the street. You avoid the "cold-start," which even in an ultra-clean hybrid, is still the dirtiest part of the fuel cycle.
This is one small but significant step by Toyota toward plug-in hybrids. The company is giving drivers a taste of the pleasure of silently gliding down the street. And it shows their marketing team is paying attention to the interest in PHEVs.
But let's not make too much fuss: if you gun the engine or go at highway speed, or once you've driven about a mile, the engine goes on no matter what. Why only a mile? Here's the technical reason: This and other standard hybrids have batteries designed to transfer large amounts of power and remain in the mid-state of battery charge (e.g. 40-60%). In contrast, PHEVs have batteries that maximize energy transfers, and charge/discharge across a much wider range (e.g. 20-90%). In practical terms, the lithium-ion PHEV Prius batteries store 20-30 times more energy than a standard nickel-metal hydride battery Prius.
Below we reprint a report and discussion at AutoblogGreen about the feature and its implications. But before, here's some background about the significance of the EV Button.
Way back in October 2003, the new third-generation Prius included a mysterious non-functional black button to the left of the steering wheel. New Prius owners (I included) discovered that in Europe and Asia, this button was marked "EV," and Americans wanted equal opportunity. One Texas engineer figured out that the American cars had the same circuitry; the wires weren't hooked up. He explained how to do it, and at PriusChat.com and at CalCars.org, we helped publish the instructions (they're still a popular download at http://www.priusplus.org). CoastalETech.com sold little kits with all the needed parts. At least several hundred people enabled the button in the U.S.
This "hidden feature" became the starting point of our online-based open-source style project that led to CalCars first PRIUS+, completed in November 2004. It facilitated the designs of other after-market conversions. At the time, Toyota said it didn't enable the button in the US because it would complicate emissions testing. This never made much sense to us. We did understand that Toyota saw enough confusion about "gas-electric hybrids" that it wouldn't want a button labelled "EV" in a car it has always promoted "you don't have to plug it in."
Toyota's FAQ warned users not to install the button. (The current version of its faq still mentions the "switch," but now reads more broadly, and confusingly, since there are 4 warranties in a hybrid: http://www.toyota.com/vehicles/2007/prius/key_features/launch_faq.html 25. Does Toyota support the modification of my Prius to be a plug-in Hybrid and run on electric mode only with a switch? Any such alterations, modifications or tampering with the vehicle voids the warranty and is likely to be counterproductive for air quality and Prius' durability and safety.
Logically, Toyota should now ship 2008 Priuses and its Lexus hybrids with the EV button enabled....
A few comments:
- Marc Geller, in his "Plugs and Cars" blog http://plugsandcars.blogspot.com/2007/02/toyota-hybrid-breakthrough-one-mile-ev.html, emphasizes that 1-mile limitation of the button has nothing to do with the the type of battery used.
- We include excerpts from the Toyota press release, noting with regret that,as it tries to out-muscle Detroit, efficiency improvements pave the way to bigger/heavier/more power. Toyota didn't mention the button; the company singles out: "four inches longer and three inches wider...The new Highlander gained about 500 pounds, growing significantly in every dimension and receiving extensive body and chassis reinforcement, aimed specifically at achieving best-in-class crash ratings. Not only were engineers able to increase output to 270 net horsepower, they were able to maintain Highlander Hybrid's impressive fuel economy at 31 city and 27 highway."
- Many reader comments show how much people yearn to drive electrically.
AutoblogGreen Chicago Auto Show: 2008 Toyota Highlander Hybrid, now with EV ONLY mode! Posted Feb 7th 2007 12:01PM by Sam Abuelsamid http://www.autobloggreen.com/2007/02/07/chicago-auto-show-2008-toyota-highlander-hybrid-now-with-ev-on/
Today at the Chicago Auto Show, Toyota unveiled the all-new 2008 Highlander Hybrid. Toyota has upgraded the control system of the new Highlander Hybrid so that they can increase the net output, which is now up to 270 hp, an increase of 55 over the first generation model. At the same time, the mileage ratings remain the same at 31 city / 27 highway. The big news, if you can call it that, is the new Full EV mode.
That means there is a switch on the dash allowing the driver to disable the internal combustion engine and run on battery only. Unfortunately, that battery is still a nickel metal hydride type, which results in a whopping battery only range of a whole mile! This really comes off as more of an advertising gimmick than anything truly useful. Aside from that, the hybrid drivetrain is largely unchanged, although everything else is. The new Highland is bigger, wider, more luxurious and has airbags everywhere including three rows of curtain airbags. The new Highlander Hybrid will be available in July.
Toyota Launches 2008 Highlander And Highlander Hybrid At The 2007 Chicago Auto Show
February 7, 2007 - Chicago - Toyota Motor Sales (TMS), USA, Inc., unveiled the all-new next-generation Highlander and Highlander Hybrid mid-size sport utility vehicles (SUV) at a press conference today at the 2007 Chicago Auto Show.
"Highlander holds a unique distinction within the Toyota brand and within the industry," said Don Esmond, TMS senior vice president, automotive operations. "Along with the 4Runner and the FJ Cruiser, it anchors one of the industry's only three-vehicle, mid-size SUV line-ups. Equally important, along with Prius and Camry Hybrid, it is a key component in the industry's only three-vehicle hybrid strategy."
The 2008 Highlander is significantly larger, roomier and more powerful than the vehicle it replaces. Yet its fuel efficiency will be virtually unchanged. It is noticeably quieter, smarter, with improved versatility and ride comfort. It will offer the highest level of standard safety equipment in a segment where safety is at the top of purchase considerations. And, it's all wrapped in a package designed for buyers who want to stand out and make a statement.
On the outside, Highlander moves away from traditional SUV styling cues with a statement of strength instead of ruggedness; of intelligence over toughness. Calty Design Research in Newport Beach, Calif. sculpted clean, crisp lines, a wide, stable stance and muscular contours to give Highlander an advanced, contemporary, forceful and dynamic personality.
Highlander rides on an all-new chassis derived from the current Camry and Avalon. It is nearly four inches longer and three inches wider, with an inch more ground clearance and three inches of additional wheelbase.
When Highlander arrives in July, it will be offered in Base, Sport and Limited grades. All three grades will be powered by a new 3.5-liter V6 that delivers an impressive 270 horsepower -- a 55 horsepower gain over the previous generation's 3.3-liter engine.
Two months later, the all-new Highlander Hybrid will arrive at dealerships. Offered in both Base and Limited grades, all Highlander hybrids will feature Toyota's advanced VDIM stability system. The system integrates: • full-time four-wheel drive with intelligence, • electronic brake and throttle control, • with true electronically-controlled active steering.
Highlander's advanced Hybrid Synergy Drive system has been extensively upgraded and refined for 2008 for both power and economy. The new Highlander gained about 500 pounds, growing significantly in every dimension and receiving extensive body and chassis reinforcement, aimed specifically at achieving best-in-class crash ratings. Not only were engineers able to increase output to 270 net horsepower, they were able to maintain Highlander Hybrid's impressive fuel economy at 31 city and 27 highway.
"As you can see, the new Highlander has raised the bar significantly," said Esmond. "Last year we did the same with RAV4. And in about a year, we'll do the same with both Land Cruiser and Sequoia. The Toyota division now markets a six-vehicle SUV lineup that appeals to specific buyer demographics and life-stages. It is a lineup that gives us enormous flexibility in responding to shifts in the marketplace. We are committed to keeping our products fresh and at the front of the pack."
1. Nickel metal hydride batteries have a cycle life of 500-1000 cycles. With a range of 1 mile, that means that the useful life of this battery in full electric mode is 500-1000 miles. That's why no "mild hybrids" have ever had a full electric mode. http://www.batteryuniversity.com/parttwo-36.htm Posted at 12:34PM on Feb 7th 2007 by Peter
5. It's not the battery type, it's the size of the pack. I go 120 miles on NiMH in my RAV4 EV. With more NiMH, the new Highlander would get more EV range. It's Toyota's decision to give you squat. Of course with more battery, logic would compel a plug to the the cheaper, cleaner, domestic electric grid. Not ready to go there yet apparently. http://www.plugsandcars.blogspot.com Posted at 1:24PM on Feb 7th 2007 by marc Geller
6. Even with a one-mile range, an EV-only option is great! How many times do you have to shuffle vehicles in your driveway by running their engine for maybe 10 or 20 seconds? This can do away with ALL of that, which is arguably the dirtiest kind of driving you could do. Kudos, Toyota! Besides... this will make is EASY to simply plug in a different (bigger) battery pack. No more hacking the system, just upgrade the battery! Sweet. Posted at 1:27PM on Feb 7th 2007 by Andrew
7. Peter: there's more info for you on the web. First, Toyota does not deep discharge its hybrid packs. The state of charge (SOC) varies between 20 and 80%. EV only mode will not disable the SOC limits. The BU article refers to full cycle in consumer electronics. Second, while Toyota's fully electric RAV-4 used different packs, these have been running for more than 100,000 miles in fleet use since the mid-1990s. Battery packs in well designed hybrids like Toyota's last for the life of the vehicle. Posted at 1:42PM on Feb 7th 2007 by Ron Fischer
8. The RAV4 uses the same battery chemistry but has a much higher capacity. That is why it lasts for 100,000 miles. Cycle Life x Range = Battery Life So 1000 cycles x 120 miles = 120,000 miles (Rav4 EV) But 1000 cycles x 1 mile = 1000 miles (Highlander hybrid) Even if they avoid deep cycle discharge, 1000 cycles is a generous estimate. 500 is more common and don't forget that the batteries in a car are exposed to heat, cold, and vibration. The bench tests from the link I sent were performed in controlled conditions. Posted at 1:54PM on Feb 7th 2007 by Peter
10. One mile seems like nothing - but people drive these distances! I'm working on a project for a town that is so unpedestrian friendly, that they drive from store to store in their business district, way less than a mile. I live about a mile from a train station, and I usually walk, but more people drive. How much do you think range would improve if you yanked out the 3.5l engine and the transmission, put in a smaller ICE engine to power the brakes, steering, etc if necessary... I think range would improve alot if you pulled all that weight. Now it is just up to owners of these new cars to feedback to Toyota and tell them to increase the range. Posted at 4:00PM on Feb 7th 2007 by Dave
12. Please keep in mind that the "EV" button doesn't add any complexity to the car -- all of Toyota's hybrids support full EV mode, and the Japanese market Prius and some European-market Prius models have come with the "EV" button for years. The performance of the "EV" mode, although very limited in range, is seamless and automatic. When the battery charge falls below a certain level, the gas engine automatically kicks in and the vehicle enters normal operation mode. It's not going to be a big feature for most people, just a fun diversion/experiment from time to time. In normal driving, the hybrid system enters "all electric" mode all the time, sometimes several times a second -- all transparent to the driver. The button just enables a part of the software which allows you to demand that the vehicle stay in that mode as long as possible. Posted at 10:23PM on Feb 7th 2007 by Bob R.