Range extender efficiency – a study of a study

With the concept of series hybrids/range-extended EVs growing in popularity, I thought it might be interesting to take a look at a study that was put out a few years ago by San Dimas, CA-based AC Propulsion. AC Propulsion constructed a towable trailer with a range-extender for their tZero prototype car. This genset was based off of a small motorcycle engine – something GM has suggested they might use for some eFlex vehicles.

AC propulsion’s used a 500cc Kawasaki engine rated at 20kW output to maintain their tZero’s battery at around 80% SOC. Without any battery supplementation, the device could achieve between 32-38 mpg. Though an interesting experiment, I think that this study was flawed in a few ways – or at least not completely applicable to future efforts.

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New look of the Chevy Volt – a detailed look and analysis

The new look of the Chevy Volt concept made it’s debut today in the form of a vague teaser image of the front end.

However, a news report shot by a local Detroit news station got inside the design center and got to see a lot more in detail. Here are some decent-sized images of what they saw:

And here are my observations:

Challenge X Equinox goes 40 miles per charge

Despite general, widespread enthusiasm, several sources in the automotive industry have thrown a lot of cold water on the Volt and non-HSD hybrids and EVs in general. Most prominently, Irv Miller of Toyota went on record describing the kind of batteries that could 1) Fit within a hybrid vehicle architecture and 2) capable of propelling the vehicle for 40+ miles as being “theoretical”.

I already took Irv to task in a prior post. However, here’s some additional evidence for why we can comfortably discount Irv as an authority on anything engineering-related. The Dept. of Energy and GM run an event called Challenge X, where university students are given a Chevy Equinox, some money, and told to go wild on improving the “green-ness” of the vehicle. One of those teams, UC Davis, has taken their Equinox, added a 1.5L Atkinson-cycle engine (pulled from a Prius, admittedly), beefed it up with bigger electric motors at each axle, and fitted some lithium ion batteries.

The result? Well, it’s a plug-in hybrid SUV that’s capable of going 40 miles on a charge!

Sorry, Irv.

Source: LA times.

Images of Volt Prototype Pack from CPI

These are images of the Volt prototype pack from Compact Power, Inc. They are courtesy of Podtech, who filmed a presentation at EVS23.

Additionally, sharp eyes will notice one frame from the video where engineers appear to be fitting electric drive components under the hood of a Chevrolet Cobalt:

LA Auto Show – Pictures and News

I finally made it out to the LA Auto Show. GM and Ford had pretty much taken over half of their respective exhibition halls. Chevy was playing up its hybrid/hydrogen/electric effort FULL FORCE. There were fuel cell cars, hybrid cars, bronzed models of hybrid tranmissions, and lots of flashy plasma TV displays playing “Gas Friendly to Gas Free” propaganda ad nauseum.

On the Scene: KillaCycle breaks its own world record

I was fortunate to see the KillaCycle at the Pomona AHDRA races this weekend. The bike set two times under 8 seconds for the quarter mile (7.82 and 7.99), to set a new world record. Pictures and a video:

Safety of A123 battery cell

With all the conversation about lithium ion battery safety, I decided to do a little 5-minute, hands-on experiment of my own to see what’s what.

AltCar 2007-Santa Monica, CA

I got the opportunity to visit the 2007 AltCar expo in Santa Monica, where they had displays for all sorts of novel solutions -EV, fuel cell, biodiesel, etc. They also had lots of test drive opportunities. Full story and photos after the jump.

Survey of USABC Contractor Lithium-ion Technology

The United States Advanced Battery Consortium is essentially a communal technology incubator for the domestic automakers, providing development funding for new technologies. At the moment, advanced lithium ion is in vogue, with several large and several small companies being contractors. However, when you take a look at the list, one rather striking feature is that the USABC chose a wide range of lithium ion approaches to fund. For example, each contractor has a very different chemistry and/or cell format. It stands to reason that the USABC isn’t putting all its eggs in one basket, and it chose to fund the most promising examples of each.

But how do the contractors stack up against one another, and what are the inherent compromises of each approach? Each company is understandably reticent to reveal their exact specifications, as it is competitive information. However, with a little clever research into published white papers and presentations, you can uncover their approximate progress relative to one another.

IMPORTANT NOTE: This is a work in progress that only uses publicly available information. Please submit rebuttals, corrections, etc, to ensure that this comparison is accurate and up to date. I have no commercial interest or financial connection to any of these companies, other than as an American consumer.

Electric Motor Comparison

I want to take what I did with battery specs, and do a quick review of the various electric motors being planned for HEV/PHEV/EV use. I’ve sampled the top spec motors from five manufacturers: UQM, AC Propulsion, Raser Technologies, PMLFlightlink, and Tesla Motors. The two really defining criteria are power density and efficiency. Increased power density reduces the weight and form factor of the motor needed for the application, and high efficiency helps reduce overall energy losses.

(click to enlarge image)