Hymotion L5 Battery Unit

Hymotion, a division of A123Systems has announced the availability of a high capacity battery called the L5 Conversion Module for the Toyota Prius that will ship to customers in July of 2008. At $10,395 delivered and installed, it’s a lot of money, equal to 2772 gallons of $3.75 gasoline. With only three years of warranty and $1000 up front to reserve one you can get well over 30 perhaps as much as 40 miles of fuel free miles if the gas engine doesn’t come on to boost power.

The Hymotion battery is a ”Nanophosphate” lithium ion battery that recharges from standard 120-volt outlets to a full charge of 5kWhs. Once discharged the Prius reverts to the normal drive cycle as originally engineered. Hymotion offers that the recharge takes 4.5 hours, the battery weighs in at 180 pounds, and is applicable to Toyota Prius model years 2004 to 2008. The only loss is carrying the spare tire as the battery and charger kit fill the spare tire well.

EnerDel’s Prius Battery Unit Prius

Coming a little later may be EnerDel’s lithium titanate battery option to a full plug in a Prius. Last week saw the announcement that the Argonne National Laboratory’s Center for Transportation Research completed tests of their 10kWh battery. The test was of a prototype unit with the battery installed to a Prius without any modifications except to integrate the battery. EnerDel has already had the Idaho National Lab test, finding that the battery has twice the energy as the stock Nickel Metal Hydride battery allowing for half the weight and size in a battery trade out.

Most interesting is the Argonne test checked the battery for heating, or the release of battery energy to heat rather than motive power and in consideration of overheating risks. Argonne found the battery running on a dynamometer would not need a cooling system. EnerDel is also reporting that the reduction in the battery’s internal resistance is down by 67% thereby passing more power out to energize the drive motor.

Argonne ran the EnerDel battery through the Federal Urban Drive Cycle test to get a comparable mileage number with other contemporary cars. The EnerDel modified Prius came in at 77.41 MPG. EnerDel is also saying they expect costs to be significantly less than the standard NiMH battery at similar performance ratings.

Where does that leave the “lucky” Prius owner? EnerDel hasn’t announced a kit to upgrade a Prius and may not. But the effort looks headed that way with the tests completed and the results so very useful for direct comparison. Comparing the City MPG from the Toyota web site at 48 MPG to the Argonne test at 77+ MPG or a 61% improvement, offering kits may be irresistible. But without a price and anticipated date, it’s a nice thing to think about and use to measure the other offerings in the market.

Hymotion is in front with a delivery date and hard pricing delivered and installed making their advantage more solid. The weakness is in the comparisons of the payback. Claims and estimations without the results of the Federal Urban Drive Cycle test which are in fact don,e showing about the same MPG as EnerDel, leaves people wondering. Peak MPG in short travel is fine, yet we need more direct comparisons.

At the end of the look, the lucky Prius owner has one certain choice and another perhaps soon. A quick look at the DOE link shows that these two are not alone and the EnergyCS may be coming, too. (Links to a pdf)

What is most reassuring is that the MPG is way past 75 MPG on longer drives and on short ones perhaps no fuel use at all. It makes one wonder what was going on when Congress set out to fight over a new MPG standard.

As for us, the next few years are going to be great. A Prius might be a little small for some of us but the Camry size covers a lot of potential buyers. A Camry might well clear 60 or 70 MPG. Put those on sale and I’ll be impressed.


5 Comments so far

  1. Conor on July 24, 2009 3:28 AM

    great stuff to kick start my creative side this AM

  2. Pelzer on May 10, 2010 10:28 PM

    Thanks for this, Ive always wondered. Great job explaining it for me!

  3. Strada Pescarusului on October 5, 2010 6:12 PM

    I think that is right bout that. Nice info and thanks. Need to get in google feed.

  4. treatment on December 12, 2010 5:48 AM

    Hrmm that was weird, my comment got eaten. Anyway I wanted to say that it’s nice to know that someone else also mentioned this as I had trouble finding the same info elsewhere. This was the first place that told me the answer. Thanks.

  5. Matthew Moat on February 2, 2011 12:23 PM

    Hi there! Would you mind if I share your blog with my myspace group? There’s a lot of folks that I think would really enjoy your content. Please let me know. Thank you

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