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First Crash-Tested Mass-Produced PHEV Conversions from Hymotion/A123
Apr 27, 2008 (From the CalCars-News archive)
This posting originally appeared at CalCars-News, our newsletter of breaking CalCars and plug-in hybrid news. View the original posting here.
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Big news from Hymotion below, but first our overview:

Ever since CalCars first turned a Prius into a PHEV in Fall 2004, we've been promoting conversions as part of a strategy to build awareness of PHEvs' benefits and support for our main goal: mass produced PHEVs from the world's large carmakers. Since then, as people have clamored for PHEVs, the pace of conversions has been frustratingly slow, with about 150 completed both from our EAA-PHEV project and from a few private companies. (Many of those cars are listed at our Where PHEVs Are page,­where-phevs-are.html .) Most have gone to utilities, national labs, and a few to early adopters. Toyota has even converted less than a dozen of its own Priuses. Now, three-and-a-half years later, many of the small companies and our "do it yourself with the help of an engineer" solution have advanced to the point when Prius PHEVs are becoming more broadly available.


  • A few weeks ago, the Wall Street Journals's Senior Automotive Editor Joseph White said,­calcars-news/­941.html PHEVs "have made the journey from the auto industry's fringes in near record time," and called the PHEV campaign "a victory for the technological insurgents who pushed the plug-in concept over Detroit and Nagoya's objections."
  • And today, Matthew Wald begins The New York Times's exclusive report (full text below) on Hymotion's launch of the first mass-produced conversions by describing PHEVs as "possibly the most sought-after technological innovation since Captain Kirk first flipped open his communicator." No wonder people have been banging down the doors of the conversion companies!

This is taken from our How To Get a PHEV page,­howtoget.html Depending on the choice of battery types, PHEVs using lead-acid are now available for $6-$10,000, nickel-metal for $8,000 and up, and lithium chemistries for $10,000 and up. Conversions are mostly for the Prius, with a few for the Ford Escape/Mercury Mariner hybrid SUVs. At these prices, people are buying the "environmental feature" -- they want to be among the first owners of the world's cleanest extended-range vehicles. They are early adopters, buying "Version 1.0" PHEVs with "Good Enough to Get Started" batteries.

In addition to our someday seeing "from the ground-up" PHEVs like the Chevy Volt, Fisker Karma, Tesla WhiteStar, and cars from Aptera, BYD, Venture and others, we believe carmakers, benefiting from economies of scale and far larger development resources, will some day extend their current hybrid lines with far better PHEVs, and we think they will be able to sell them for $3-$5,000 more than standard hybrids. At that point, we expect the aftermarket companies' prices to have come down sufficiently so that their conversions will be attractive to owners of hundreds of thousands of hybrids already on the road.

The nonprofit CalCars does conversions to demonstrate new designs and provide a platform for different batteries; we don't sell conversions. We have sponsored the EAA-PHEV project -- our Open-Source designs are being used by some of the private companies as well as technically advanced individuals. We maintain links to the companies offering conversions at the CalCars "How to Get a PHEV" page,­howtoget.html .

In May 2007, Canadian company Hymotion was acquired by Massachusetts batterymaker A123Systems, which thereby became a source for aftermarket conversions as well as a vendor offering its pto carmakers -- including contending for the prize of supplying batteries to GM for the Volt and the Saturn Vue. Since then, its conversions have showed up at the White House, Google and many other locations. Now it's announced the launch of its consumer product: $9,995 + $400 delivery for a 5kWh battery pack. It gives you a 30-40 mile all-speed boosted range at 100+MPG plus about a penny a mile of electricity. Hymotion has not-yet-identified installation centers in Boston, Washington, DC, Minneapolis, Seattle, San Francisco and Los Angeles. It's offering a three-year warranty to start, with additional possible warranties in the future. (To GM, A123 says it believes its Nanophosphate lithium batteries will to meet GM's criteria of 150,000 miles/10 years.) Its crash-tested system has received federal NHTSA and FMVSS safety approvals and conditional California certifications. The batteries go under the rear deck, in the area usually occupied by a tool tray and the "doughnut" (minimal spare tire). The company's revamped website at includes a handy calculator where you can enter your driving patterns etc. and compare the fuel and greenhouse gas results with an internal combustion car and a standard Prius. It's taking $1,000 deposits for delivery of cars this year. (One of our correspondents who signed up on Day One told us he was #114 in the queue.)


  • Hymotion's letter to those who had asked get their latest news
  • Excerpts form the website's blog discussing California certification, etc.
  • Excerpts from its FAQ about those warranty issues that always come up
  • The New York Times story (complete version)

Greetings from the A123Systems Hymotion product line team!

Thank you for your interest in our product line and for filling out our Hymotion request form. We know that many of you registered for updates quite a while back and have been patiently awaiting news of our product development progress. We apologize for the silence over the past year, but assure you that we have dedicated ourselves over that time to completing development and testing of our first product, the Hymotion L5 Plug-in Conversion Module (PCM) for the 2004-2008 Toyota Prius. We have recently added several new members to the Hymotion management and customer service teams that will enable us to better respond to your questions and orders as we now move into commercial production and sale of the L5.

Over the past year, with the help of our fleet and demo partners, we have completed the field testing and product development protocols to produce the market’s first fully tested, standardized and publicly available PHEV conversion module - the Hymotion L5. We have released the product to mass production and are now offering the L5 for purchase by consumers, as well as fleets and government programs. Lead times for each customer will depend on overall demand and product availability, but we expect consumer deliveries to begin in July 2008.

We are happy to announce that our new Hymotion website launched today with consumer order capability! We are committed to ensuring that those of you who have already expressed your interest in our products are given priority for product delivery. If you are interested in purchasing the L5 for your Prius, please reply to this email to indicate your purchase intent AND place your deposit online on our new website to initiate your order. A member of our customer service team will respond to you with further information regarding your order within 5 business days.

Thank you for your loyalty and your patience over the past year. We appreciate your interest in our Hymotion L5 conversion modules and your support of plug-in hybrid technology! Again, if you are interested in purchasing an L5, please respond to this e-mail indicating your purchase intent to ensure your priority for delivery of an L5 AND place a deposit online to initiate your order. We hope that we can serve you as customers soon!

FROM HYMOTION'S BLOG­blog/­hymotion Other Hymotion Highlights:

First Hymotion PHEV Conversion for Individual Consumer Completed We recently completed the first conversion of a privately owned Prius into a Hymotion PHEV with our L5 PCM, which we unveiled at the Washington International Renewable Energy Conference in Washington, DC on March 5th. James Woolsey, Former Director of the CIA and ardent spokesperson for US independence from foreign oil, now has the first privately owned Hymotion PHEV in the world. President Bush also stopped by our booth to check out the Hymotion PHEV:­index.php?article=344.

Hymotion Dealer Network We are currently establishing and certifying our A123 Green CHIP (Certified Hymotion installation Partner) dealer network in major cities around the country. Initial Green CHIP dealers will be located in Boston, Washington, DC, Minneapolis, Seattle, San Francisco and Los Angeles.

California Air Resources Board Approval In April 2008, in the absence of established PHEV certification procedures, the California Air Resources Board (CARB) working together with our team outlined a path for conditional approval for A123Systems to sell up to 500 L5 PCMs in California as a means of initiating our rollout to consumers. We are now in the process of finalizing that approval. Additionally, we and others are also working with the CARB to establish certification procedures for PHEVs. Once those CARB PHEV certification procedures are final, we expect to certify our Hymotion L5 for sale in California under those procedures with no restriction on quantities sold.

FROM HYMOTION'S FAQ: WARRANTY ISSUES­hymotion/­products/­faqs

The L5s have a standard 3 year warranty. Additional warranty options may be offered at a later date. Will the Hymotion conversion alter the warranty given by the vehicle's manufacturer?

Federal consumer protection laws do not allow a vehicle's OEM to void a consumer's warranty for installing a Hymotion module unless the Hymotion module is the direct cause of an otherwise warranted problem. For example, Toyota shouldn't void your warranty on your headlights for putting a module in your trunk. The Hymotion L5 is engineered not to adversely affect any OEM-warranted system. Our product field testing of over 200,000 miles of real life driving did not show any otherwise warrantable problems on the stock vehicle caused by the L5. If a vehicle's OEM denies a Hymotion customer warranty service due to a problem caused by a Hymotion module, A123 will pay for the otherwise warranted repair. SEMA, the Specialty Equipment Market Association provides guidance on understanding the legal protection for aftermarket products, specifically the Magnuson-Moss Warranty Act. Click here for more information.

THE NEW YORK TIMES EXCLUSIVE STORY APRIL April 27, 2008 [This is the online version; the print version was half as long and lacked the zingy intro] A Plug-In Conversion for Prius By MATTHEW L. WALD­2008/­04/­27/­automobiles/­27PLUGIN.html?

WASHINGTON: Possibly the most sought-after technological innovation since Captain Kirk first flipped open his communicator is the plug-in hybrid, a vehicle that runs first on a battery charged from house current, and then on gasoline.

Big car companies have talked about it, but they do not yet sell plug-ins. Beginning this week, a company in the Boston area will be taking orders for what it says is the first mass-produced aftermarket conversion kit. The company, A123 Systems, is starting out with the Toyota Prius, with what it calls a range extender module. The module fits in the well normally occupied by the spare tire, with a charging port installed on the back bumper.

The A123 conversion will allow a Prius driver to substitute electricity, at about 3 cents a mile, for gasoline at three or four times that price. And it would let the United States shift toward the use of coal, wind or sun energy sources instead of imported oil.

About 50 converted vehicles are already in service around North America, some for more than a year, but so far they have been available only to fleet or institutional buyers.

The module carries 5,000 watt-hours of usable energy, compared with about 300 watt-hours for the battery that is built into the Prius, the one that is charged by the engine, or by electricity generated as the car slows down. That one is charged when the car’s brain decides it is time; the one that A123 adds takes about four hours to charge on 120-volt household current.

Leslie J. Goldman, the Washington lobbyist for A123, opened the hatchback of his Prius, pointed to an orange extension cord coiled in the back and said: “That’s the only infrastructure you need!”

In most parts of the United States, a full charge would cost 60 cents or less. How much extra range the car gets depends heavily on the driver — as does everything in the Prius.

“If you drive like a maniac, you get about double the Prius mileage,” Mr. Goldman said. With a lighter touch, a driver can get a lot more, at least until the charge runs out. In city driving, the battery could give an extra 35 or 40 miles, he said. That may be more miles than the car goes in a day.

A driver who could plug in while at work could get 60 or 80 miles a day on the electric drive system, although most people have a much shorter daily itinerary.

The A123 conversion makes barely any changes to the car. Electrically speaking, it sits between the original battery of the Prius and the car’s computer, serving as a buffer for the factory-installed battery. Mostly what it does is tell the Prius that there is still lots of charge remaining, and thus no need to start the car’s engine to recharge the battery.

Driving around Washington last week, the Prius engine started up as normal whenever the combination of the accelerator pedal position and the grade of the road demanded more torque than the electric motor could deliver. Stomp on the gas, so to speak, and the Prius drew energy from both the internal combustion engine and the combined battery pack.

Maximizing the value of the extra watt-hours requires the same expert touch that driving a stock Prius does. So I recruited a self-described Prius geek, Charlie Richman, who lives in Bethesda, Md., and drives to his job in the District of Columbia municipal planning department in a Prius that is still equipped as Toyota built it.

“Very cool,” said Mr. Richman, test-driving the battery-equipped 2007 Prius.

Mr. Richman said that the car “handles just like a Prius.” But there is a difference. In his own car, when he accelerates gently and drives for extended periods at just below the level that causes the gasoline engine to kick in (though eventually it will to re-charge the battery). With the A123 pack installed, the gas engine never had to do that, at least not in the 10 miles or so that he cruised along North Capitol Street and then New Hampshire Avenue N.W., four or six-lane city streets with a few straightaways and frequent traffic lights.

The Prius comes with an instantaneous fuel economy gauge that runs up to 99.9 miles per gallon, but A123 installs another with an extra digit. After I drove the Prius for a distance the gauge said my mileage was in the 80’s, but Mr. Richman quickly moved the average back up over 100. (The test car was covered with decals proclaiming 120 miles per gallon.)

A123 uses a battery technology it calls lithium ion nanophosphate, developed at M.I.T. It stores 5,000 watt-hours in a 140-pound module. In comparison, Toyota’s nickel metal-hydride battery weighs about 100 pounds and holds 1,300 watt-hours.

But to increase the longevity of the nickel metal-hydride battery, the powertrain control control of a standard Prius keeps the charge from falling more than a few percentage points below 50, so its 1,300 watt-hour battery is effectively much smaller. A123 says its battery will withstand 7,000 cycles of full charge and then discharge. At a charge a day, that is longer than the likely life of the Prius.

The warranty is a bit more modest, at three years. David Vieau, president and chief executive of A123, said the battery had been tested in hot and cold conditions, and was legal to install because it reduces the already-low emissions of the stock Prius. He also said that it would not void the Toyota warranty because it does not alter the function of any Toyota system. Toyota, though, has yet to be heard from on that point, he acknowledged.

(Martha Voss, a spokeswoman for Toyota, said that an after-market part would, in fact, void the warranty if Toyota decided it was responsible for the failure that occurred; this would be determined on a case-by-case basis, she said. Toyota is working on its own version of a plug-in, she said, using in-house engineering.)

A123’s long-term goal, though, has always been to sell its batteries to companies like Toyota. Mr. Vieau said he had gotten into the aftermarket parts business backwards.

“It’s hard to sell to the car guys unless you are already in mass production,” he said, so the company began with a smaller market: power tool manufacturers. Soon, though, it found that a tiny Toronto company, Hymotion, was buying its batteries and assembling them into conversion kits for the Prius. Mr. Vieau said his company was worried that untrained mechanics could build an unsafe car.

So A123 bought Hymotion, which had done only a handful of conversions but had extensive experience in hybrid vehicles. Now A123 has six approved installer companies around the country and is planning to add more, he said.

But selling to General Motors (A123’s batteries are being tested in G.M.’s development program for the Volt plug-in hybrid) or other manufacturer would make life simpler, said Ric Fulop, A123’s founder and vice president of business development; that would simplify charging systems, cooling systems, packaging and other aspects, he said.

As an add-on, the A123 module is a bit cumbersome and quite expensive, $9,999. Using a calculator on the company’s website,, a shopper can enter his anticipated daily mileage and see the savings in fuel and carbon dioxide. For example, a 16-mile-each-way daily commute, half city and half highway, and a total of 12,000 miles a year, saves about 162 gallons a year compared to an ordinary Prius. (A problem in a way, is that the A123 module is an add-on to an already-efficient car, and thus saves a substantial fraction of a number of gallons that is small to begin with.) That indicates a payback period of more than 17 years. If a shopper anticipates a tax on carbon dioxide of, say $20 a ton, that reduces the payback period by about a year.

But a shopper who drove more miles and could recharge at mid-day, and who expected gasoline prices higher than the mid-$3 range over the lifetime of the car, might find the economics better.

“If the price of fuel stays at $3.50, we’d agree that for most people this is a marginal case,” said Mr. Vieau. The target market is clearly first-adopters with some disposable income.

As with all great energy innovations, the next thing the inventors want is a tax credit for their product, just as the Prius and other hybrids got. That would allow manufacturers to build volume and cut costs, they say. A123 says costs could fall 20 or 30 percent in the next few years just on volume.

For Mr. Richman, the conversion might not be cool enough to justify the $9,999 price. “If I had $10,000, I’d be half way to a new minivan,” he said, adding that he would like to find something more efficient than his Honda Odyssey. Strictly speaking, the Prius itself may not have been an economic choice, he said, “but I convinced myself it was almost neutral” in dollars, and worth it because it reduces the family’s carbon footprint, he said.

But for the time being, the discussion of how best to spend $10,000 is hypothetical, he said, because “I don’t have $10,000; I have children.”

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