It does tickle me seeing such a luminary engineering setup like Bosch making such a silly mistake after Tesla has 'been there, done that'. It may turn out well for them but it seems a bit arrogant when you consider how much a success Tesla has had after just 1/10 of the time all the big automakers have been around for, and yet 'they know better'! Well, it'll be interesting to see if it lasts or whether they'll go back to having a single speed transmission on the end.
Of course, it could just be a cunning ploy to build some cash revenue onto their EVs. After all, it'll need *some* maintenance! MW On 21 Jul 2014, at 15:55, Bill Dube via EV wrote: > Remember that the early Teslas had a two-speed transmission that proved to be > a disaster. They cured the problems by simply removing the source of the > problem: The transmission. > > If you install proper motor cooling and controller cooling, and perhaps > upgrade the motor or controller, then the desire/need for a transmission > naturally goes away. > > There is really never a need for a transmission in a well-designed EV. It > adds complexity, cost, and inefficiency. > > It is a red flag to investors when a start-up EV company proposes using a > transmission. It shows they have not really done the modeling correctly, or > they have installed a mismatched drive system and are trying to "fix" it with > a transmission. > > Bill D. > > On 7/21/2014 7:44 AM, brucedp5 via EV wrote: >> >> Bosch sez Gear changes will soon be part of EVs >> >> http://ecomento.com/2014/07/14/prototype-golf-proves-gears-make-electric-cars-go-further/ >> Prototype Golf proves gears make electric cars go further >> July 14, 2014 – Stephen Edelstein >> >> [image >> http://cdn.ecomento.com/wp-content/uploads/2014/07/step2-electric-golf.jpg >> ] >> >> Thanks to their instantaneous torque delivery most electric cars get along >> with a single forward gear. BMW, Nissan, and Tesla all employ this strategy, >> yet German automotive supplier Schaeffler thinks more is better. >> >> The company entered its STEP2 prototype in the fifth Silvretta E-Rally in >> Montafon, Austria, to test a new two-speed transmission that it believes can >> improve the efficiency of electric cars. >> >> Schaeffler stripped the internal combustion powertrain from a Volkswagen >> Golf, adding a complete electric powertrain and the novel transmission, >> which features a low gear for traction and a high gear for higher-speed >> cruising. >> >> The company says the STEP2 has already achieved an efficiency improvement of >> around six percent over a comparable electric car in simulations and tests. >> That’s six percent more energy that can go towards increased range. >> >> Internal combustion-engined cars need a spread of gears to match road speed >> with engine speed, but since electric cars produce all of their power no >> matter what speed the engine is turning, multiple gears have largely been >> viewed as unnecessary. >> >> Schaeffler believes an additional gear will allow the motor to work less >> hard to propel the car at a given speed, improving efficiency. It’s like a >> riding a bicycle: a gear that works well for sustained speeds might require >> more effort from the rider when starting out. >> >> That makes for a tired cyclist, but also a less-efficient electric car. The >> harder the motor has to work, the more electricity is required to keep the >> car moving. >> >> The STEP2 doesn’t exactly put an abundance of power at the driver’s >> disposal. Its output is just 50 kilowatts (67hp) in continuous operation, or >> 70 kW (93.8hp) at peak. >> >> The Silvretta E-Rally is the perfect place to test this setup. Unlike >> conventional road rallies, where the object is to complete a set of stages >> in the shortest elapsed time, victory in the E-Rally goes to the team that >> finishes with the least amount of energy used. >> [© ecomento.com] >> >> >> >> http://www.fleetnews.co.uk/news/2014/7/14/gear-changes-will-soon-be-part-of-evs-says-bosch/52966/ >> Gear changes will soon be part of EVs, says Bosch >> 14/07/2014 >> >> Transmission technology will soon find its place in electric vehicles (EVs), >> just as it has in petrol and diesel vehicles, according to Bosch. >> >> Electric motors have no difficulty in running up to 20,000 revolutions per >> minute (rpm) – compared to petrol or diesel engines, which usually only run >> up to a maximum speed of around 9,000 rpm – and so can run in a single gear, >> without the need for a transmission. >> >> To think of transmission and electrification as opposites is a >> misconception. Whether you're talking about an electric drive or a petrol or >> diesel engine, the right transmission will make any engine more efficient. >> >> As electric vehicles become more popular, motorists are being introduced to >> automatic vehicles that do not use traditional transmission. >> >> Most electric vehicles effectively operate in one gear without any need to >> change up or down – with reverse and neutral as the only options. >> >> Bosch believes that changing gears will soon be part of the electric >> vehicle. High-precision automatic transmissions are essential in hybrid >> vehicles to ensure that the combustion engine and electric motor are >> synchronised with each another, but such transmissions could also find their >> way into pure electric vehicles. >> >> EV sales predictions >> >> Looking at all new vehicle sales worldwide in 2020, Bosch expects at least >> 6.5 million hybrids, 3 million plug-in hybrids, and 2.5 million all-electric >> vehicles, alongside some 100 million petrol and diesel cars. >> >> In 2013, there were 1.5 million hybrids, 90,000 plug-in hybrids, 100,000 >> all-electric vehicles and over 60 million petrol and diesel cars sold >> worldwide. >> >> In 2013, more than half of all new cars and light commercial vehicles sold >> had an automatic transmission. In future years, Bosch believes automatic >> transmissions will increasingly overtake manual transmissions worldwide. >> >> In terms of the future, the biggest driver for modern transmissions is the >> desire to reduce CO2 emissions, according to Bosch. >> >> They are primarily designed with one goal in mind and that is to keep the >> engine as close to its optimum operating level as possible. >> >> There are already some very efficient nine-speed transmissions on the >> market, and it's only a matter of time before ten-speed designs come along. >> [© fleetnews.co.uk] >> ... >> http://gas2.org/2014/07/20/bosch-electric-cars-will-soon-transmissions/ >> Bosch: Electric Cars Will Soon Have Transmissions >> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
