DaimlerChrysler to Launch Mercedes Mild Hybrid in 2008
17 July 2006
 |
| Mercedes’s concept “Direct Hybrid”: an S-Class gasoline-electric mild hybrid, shown in 2005 |
Handelsblatt. DaimlerChrysler will bring a Mercedes gasoline-electric hybrid to the market by the beginning of 2008, according to DaimlerChrysler Board Member Dr. Thomas Weber.
In an interview with the magazine WirtschaftsWoche, Weber said that the company will commercialize an S-class mild hybrid, and that further mild-hybrid models are in development for subsequent years.
At last year’s Frankfurt auto show, DaimlerChrysler introduced both gasoline and diesel Mercedes mild-hybrid concept cars based on the S-Class. (Earlier post).
 |
| The S350 Direct Hybrid is based on a new V6. |
The S350 “Direct Hybrid” prototype is a V6 gasoline hybrid that uses DaimlerChrysler’s second-generation spray-guided gasoline direct injection in a 3.5-liter, 4-valve V6 with fully variable valve timing.
With the spray-guided direct injection process, the Direct Hybrid 3.5-liter V6 generates an output of 215 kW (292 hp) at 6,000 rpm. Its maximum torque of 365 Nm is already accessible at 2,400 rpm and remains available over a broad range of engine speeds up to 5,000 rpm.
The exhaust treatment for this layered direct injection process takes place in the double-stream exhaust system. A NOx trap system for reducing the nitrogen oxides is also used, in addition to the two bulkhead catalytic converters and controlled recirculation of exhaust gas in each branch. The results meet both current Euro-4 exhaust emissions standards and the forthcoming Euro-5 limits.
A 6kW electric motor is installed between the concept’s engine and the 7G-TRONIC automatic transmission’s converter. Depending on the driving situation, it functions as a starter or a generator, and provides a tractive boost on startup—up to 250 Nm upon ignition, with 50 Nm of torque at 1,000 rpm—and at other points during operation.
The S350 concept uses a lithium-ion battery pack for energy storage.
The combination of motor and engine boosts the maximum available torque to 395 Nm and makes the vehicle’s starting characteristics powerful.
The concept mild Direct Hybrid consumes 8.3 liters of gasoline per 100 km (34 mpg US). Compared with its predecessor model, the S 350 V6, the power has been increased by 19% and the consumption cut by 25%.
Maybe the 250 Nm elec torque should be 25? 365 Nm (gas) + 25 Nm (elec) = approx 395 ...
Posted by: JN2 | 17 July 2006 at 08:41 AM
No, it's 250 Nm electric upon ignition, 50 Nm at 1,000 rpm, for total combined torque of 395 Nm. I'll clarify above.
Posted by: Mike | 17 July 2006 at 09:00 AM
Note that it says "Maximum available torque". The 250N-m of torque from the electric motor is near 0rpm. At peak torque for the gasoline engine the electric motor will have significantly less torque available being that it is only a 6kW motor.
Posted by: Patrick | 17 July 2006 at 09:13 AM
Doesn't the teeny-weeny Insight have an electric motor almost twice the power of this one? When they say "mild" hybrid, they really mean it!
Posted by: clett | 17 July 2006 at 09:14 AM
JN2 -
the whole point of a hybrid is that the electric motor delivers torque at low RPM where the gasoline engine cannot. In this particular case, the electric motor is a stop/start device and also provides launch assist from standstill.
Clett -
strange how Americans only value something if its bigger and brawnier than the next guy's. First it was skyscrapers, then cubic inches, now apparently it's electric traction motors. Enough already with this puerile nonsense.
An S-class Mercedes is in a rather different league than a Prius. Most of the customers are over 50 (if not over 60) and may be prepared to pay a little bit more for hybrid bragging rights but they still want a big naturally aspirated engine and the associated sound under the hood. A four-banger, no matter how super-duper-efficient, simply won't cut it in this vehicle category.
Besides, mild hybrids get you something like 80% of the benefits for less than half the cost of a full hybrid. Most analysts think they hold more appeal for the European market. The Lexus 450h may reveal if that perception is correct or not, but that brand has little market share in Europe.
What surprises me is that Mercedes is not going with the two-mode hybrid they've been developing with GM and BMW. Perhaps they felt that going with a Li-Ion battery pack first was more important, or perhaps the two-mode is simply not as far along as the triumvirate has claimed.
Posted by: Rafael Seidl | 17 July 2006 at 09:47 AM
Rafael :
Don't treat clett as if he was American... because he lives on the other side of the Atlantic Ocean ! Me too, but on the other side of the Channel ;-)
And yes, electric power can be important for fuel economy - especially when considering regenerative braking efficiency.
Posted by: François | 17 July 2006 at 10:09 AM
since when is the 450h a mild hybrid anyway.
Posted by: lensovet | 17 July 2006 at 10:55 AM
34mpg (US) is outstanding for a big luxury sedan like this. Consider that the owner is probably not too concerned with gas prices, so getting him/her to use less resource is all to the good. Need to get this tech into more mass market vehicles, however, so if it provides a model for a more cost-effective hybrid, I'm all for it.
Posted by: Nick | 17 July 2006 at 11:01 AM
This is a vehicle ,powered by a powertrain, I have absolutely no interest in.
What our country and world needs is a four-passenger vehicle that weighs around 700 kilos and gets at least 100 mpg. It must be cheap and fast to build and able to turn a good profit at $15K.
Design and produce such a vehicle and the world will beat a path to your door. You won't ever be able to meet the demand.
It could have, and should have, been done thirty years ago.
Posted by: Lucas | 17 July 2006 at 11:48 AM
Clett -
my apologies for assuming you were an American. Apparently there are bigger-is-better guys on both sides of the Atlantic.
lensover -
the 450h is a full hybrid, that was my point - it will help prove or disprove the hypothesis that Europeans prefer their hybrids mild, if at all.
Lucas -
fortunately for the environment, cars like the S-class Merc are only built in small numbers. Wrt to something more along the lines you are suggesting, look at
http://www.loremo.com
Granted, it's only a 2+2, the rear sears face backward and especially, there are no side doors. However, the base model will is estimated to come in at over 150 MPG (diesel), weight is ~500kg and price is below $15k.
More conventional chassis designs, weakened by the presence of side doors, feature more sheetmetal to meet crash tests. Curb weight for a European subcompact (Opel Corsa) is around 1000kg, fuel economy is 40-55MPG combined depending on engine and transmission. The price would be in your range, though. Cars of this size have been on the road in Europe for well over 30 years.
Posted by: Rafael Seidl | 17 July 2006 at 12:50 PM
Is the erosion of "hybrid == super efficient" a bad thing?
On the one hand, we're just starting to see legislation that favors hybrids. With weak hybrids, that legislation has less bang for the buck, and may get its plug pulled more quickly.
On the other hand, more hybrids means more experience building them, suppling their parts, and repairing them. This should result in lower per-vehicle ownership costs in the long run, which helps make hybrids affordable for more people.
I think the more hybrids, the better. We'll be better for it in the long run. Hybrids aren't the solution to all our problems, but they'll help hold off peak oil and reduce global warming impacts while we progress to the next step in the journey to a solution.
Posted by: stomv | 17 July 2006 at 01:00 PM
great to have a company to start gaining the profits of a Li-Ion battery pack which hopefully won't die after just 4-5 years, in addition with the spray guided lean burner, its just great for a cross country trip through the US and still efficient enough for the citytraffic,
Posted by: Sebastian | 17 July 2006 at 01:09 PM
Rafael- Thank you for the info on the Loremo. I would most certainly buy one tomorrow were they in production.
I have long promoted the two-cyclinder turbo-diesel hybrid as the most efficient powerplant for sufficent personal automotive transportation
Posted by: Lucas | 17 July 2006 at 02:10 PM
Rafael:
6 cylinder engine feels (and in fact is) much smother in power delivery, is quiter and generates less vibration. In real world it is a must to luxury cars buyers, so DC is right in their choice. 25% reduction in fuel consumption due to lean burn (while retaining low emissions due to NOx adsorber) is great achievement, as we discussed before.
The only question I have is how powerful battery is to support AC unit during engine shut-off? If it is not powerful enough, start-stop feature will be nullified in most driving conditions.
Posted by: Andrey | 17 July 2006 at 03:25 PM
34mpg in an S class is quite an accomplishment. Its ok to get the mpg boost in ways other then a full hybrid. The point is how well it does in the real world. This looks good.
Posted by: hampden wireless | 17 July 2006 at 05:25 PM
Hi Rafael,
I'm certainly not one of those "bigger is always better" types, but I do think 6 kW in a car of this size and weight barely qualifies it to use the term hybrid.
It's little more than a stop-start system, just like you get on the tiny, basic Citroen C2. You don't hear Citroen publicising it as a mild-hybrid. I agree that such systems are a cost-effective way of saving fuel, but to call it a hybrid when the motor contributes less than 2.8% of the engine output is just a marketing ploy to try to capture some "hybrid" high-ground!
Posted by: clett | 18 July 2006 at 02:20 AM
Does anyone have any information on the battery voltage and Ah capacity?
With regard to the size of the e-motor and whether or not the "qualifies" as a hybrid, bear in mind that start-stop is a valid HEV function, as is the regeneration that is facilitated by the e-motor. If you look at the earlier post, the Direct Hybrid engine has an increase in output of 19% and a decrease in fuel consumption of 25% relative to its predecessor. Pretty darned good in my book.
Presuming also that this e-machine replaces the standard alternator, you're picking up at least a 20 to 30 percentage point improvement in the charging efficiency by going to an inverter-driven ac motor.
Some of you folks should stop being so fastidious about what is called a hybrid and be a little more open to incremental improvements, which in reality is the way the world generally works. DCX - and GM and probably Ford and others soon - should be congratulated for the mild- and micro-hybrid products they are bringing out.
And while I'm venting, it sure would be nice if you gentlemen would be a tad more charitable to we Americans. Lest we forget, who do you think invented the transmission that made the Prius famous?
Posted by: Roy | 31 July 2006 at 04:47 PM