EnerDel Unveils a Lithium Ion Powered Prius

One of the industry’s top contenders in the race to manufacture more powerful next-generation batteries for the auto industry has integrated a lithium ion battery into a Toyota Prius. EnerDel, based in Indianapolis, Ind., exhibited the research vehicle with the new battery pack at the International Electric Vehicle Symposium (EVS-23) in Anaheim, California.

EnerDel’s demonstration vehicle is not a plug-in hybrid and does not replace the Prius’s existing control systems. Instead, it demonstrates how lithium ion batteries can double the amount of electric energy storage while taking exactly the same space as the Prius’s current hybrid batteries.

"We have made a major stride toward providing the power, safety, and affordability that the market has been waiting for," commented Ulrik Grape, Ener1 Executive Vice President for Global Sales and CEO of EnerDel. "We believe that ours is the safest high-power lithium ion battery available for hybrid electric vehicles."

The transition to lithium ion from the current nickel metal hydride battery technology found in today’s hybrids could allow gas-electric vehicles to stay in all-electric mode for greater distances—substantially increasing the fuel economy. The exact benefit of EnerDel’s Prius—in terms of mpg—will not be known until EnerDel releases third party testing in early 2008.

One More Step Toward Lithium—With or Without Plug

A number of battery companies, utilities, advocacy organizations and individuals have used lithium ion batteries to convert Priuses into plug-in hybrids. In fact, Toyota exhibited its own plug-in Prius research vehicle at EVS23. As with the independent plug-in conversions, Toyota’s plug-in Prius require space beyond the compartment found behind the back seat which houses the conventional Prius’s battery pack. The conversions usually usurp the space provided for the spare tire. Toyota opted for nickel metal hydride for its plug-in prototype to produce a vehicle that can travel further in all-electric range than conventional hybrids (approximately seven miles), but not as far as if lithium batteries were used. The company has not announced any plans to bring a plug-in Prius to market.

Many industry observers had expected the next generation plug-less Prius, due in 2009, to use lithium batteries. But Toyota announced in May 2007 that the company’s flagship hybrid would continue using nickel metal hydride batteries. The decision reflects Toyota’s strategy to protect its lead in the hybrid market, rather than taking chances with lithium batteries that carry greater cost and safety concerns.

EnerDel’s lithium-powered Prius is one more step in what many see as a likely transition of auto batteries to lithium technology—first in conventional hybrids and then in plug-in hybrids and electric vehicles.

 


  • Charlie

    “The transition to lithium ion from the current nickel metal hydride battery technology found in today’s hybrids could allow gas-electric vehicles to stay in all-electric mode for greater distances—substantially increasing the fuel economy.” What’s the logic here? The battery still has to be charged by the gas engine; a battery with more capacity just means that the time to fully charge it is greater. In the limit, the time to discharge the battery doubles, but the time to recharge it also doubles. The gas milage would seem to be unchanged.

  • Stan Smart

    Each new breakthru in battery
    technology changes the storage
    equation in several ways.

    Storage is one; charge time is another. Li-Io batteies charge much more quickly than any
    previous technology. Another
    idea for electric storage is the
    capacitor. Capacitors store electricity almost instantly, but they discharge fast, also.

    Several companies are working on
    battery – capacitor “hybrids” to improve storage AND charge times.

  • Fred Thomley

    Charlie obviously doersn’t own a hybrid! The Batteries are also charged by BRAKING!!!

  • Van

    I agree Charlie, if you just double the battery capacity and do not change the existing control system, the fuel economy would probably not be better. However, the next generation Prius, apparently due out in the spring of 2009, is expected to have a larger NiMH battery (2.6 KWH instead of 1.3 KWH). This new Prius is expected to get about 20% better mileage than the existing Prius (about 54 MPG overall versus the existing 46 MPG). It is also expected to be able to operate in “All Electric Mod” (stealth mode) up to 62 MPH for a range of around 7 miles. So it would seem to be a half step toward offering a Plug-in version of the Prius in the future.

    What is interesting is that this battery from EnerDel would seem to be a perfect fit for the next Prius, if it has the safety and the cycle and calendar life properties implied by the article.

  • Dave K.

    The relationship between battery capacity(both power and energy) and mileage in a hybrid is very complex, as Fred mentioned regenerative braking is a very demanding event for any battery, if it has too high an internal resistance some of the energy will be converted to heat and thus wasted. Also if the hill is too long the capacity may be insufficient. Also, a large amount of the fuel savings in a hybrid comes from running the engine in the higher power more efficient range for a shorter time, thus more capacity would enable longer electric periods punctuated by shorter, more efficient engine cycles. From the CalCars guys I know the Prius Nimh battery is far from ideal in both power and energy density. EnerDel’s battery represents real improvements, unfortunately since Toyota owns a big piece of Panasonic they’re unlikely to use anyone else’s product.

  • Harold

    Prius is not the only hybrid out there. Maybe the biggest sellar.

  • DaveM

    give some of the other posts tha toyota themselves might not be the primary market for this battery, but companies doing well using licensed copies of the toyota system.

    They should be looking at Ford and Nissan and offering them this product as a future way to make their hybrids stand out from the “stock” system they aquired from Toyota.

    One goal may not be to improve the capacity of the battery, but shrink it for the sedan market. The more weight/trunk space you recover, the more attractive the Hybrid becomes for the non-hybrid focused buyer

  • otto

    overall resistance in
    charging/unloading the batteriepack
    is crucial.
    Lithium-ion is only part of that.
    Improved capacity is nice
    when going down-hill.
    Remember Priusrecords of 100mpg
    were made AVOIDING at all use of the batteriepack.

    It was the puls-glide way
    that can do without it.

  • Charlie

    Thanks, all, for the input. It was refreshing to be part of such a civilized discussion. :-) You have given me a lot to mull over. Perhaps much of the benefit of a new battery system comes from the non-linear efficiency improvements in the charging cycle of the gas engine (as a charger)and the charge/discharge cycle of the battery. So it’s not as simple as doubling the battery capacity equals better milage.
    No, I don’t have a hybrid yet. It’s a little like buying a new PC — they are good today, but they’ll be so much better tomorrow! I’m thinking, I’m thinking… :-)

  • Indigo

    Doubling the battery capacity would help out a lot in hilly terrain. My HCH sometimes goes down to one “bar” of charge when driving on the PA turnpike. When that hppens, the IMA stops offering assist and the fuel economy drops a lot.

  • khooper

    There are only so many ways the Car Tech can be used. None of them involve any sort of recharging in a way that we would recognize as hybrid tech.