Chapter

The Voltec System: Energy Storage and Electric Propulsion

DOI: 10.1016/B978-0-444-59513-3.00008-X In book: LITHIUM-ION BATTERIES: ADVANCES AND APPLICATIONS, Edition: 1, Chapter: The Voltec System: Energy Storage and Electric Propulsion, Publisher: Elsevier, Editors: Gianfranco Pistoia, pp.151-176

ABSTRACT

Vehicle electrification is progressing significantly and is changing the architecture of future cars. This trend is a result of the need for higher vehicle efficiency and the desire to diversify the energy sources used for transportation. Voltec vehicles such as Chevrolet Volt and Opel Ampera are electric vehicles (EVs) with extended driving range. They operate as an EV as long as there is useful energy in the battery. However, unlike a pure battery EV, they do not suffer from lost vehicle utility when the battery is depleted. Volt and Ampera can continue operation by using an internal combustion engine as energy converter. Within the framework of this chapter, in addition to the focus on the current Voltec battery and propulsion system technologies, a brief history of the General Motors EV activities is also provided.
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Keywords: Battery, Chevrolet Volt, Opel Ampera, Propulsion system, Voltec.

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Questions & Answers about this publication

  • Ulrich Eberle added an answer in Electric Vehicles:
    Can anyone help me to find the distribution percentile of NiMH, Li-ion, LiPO, etc... in electric vehicle?

    I'd like to have an idea on the distribution of these technologies in modern EV.

    Any help would be appreciated, thanks!

    Ulrich Eberle

    Julien, I can only second Markus Lienkamp's point considering modern EVs (covering not only pure battery EVs, but also valid for extended-range EVs). Various aspects of vehicle electrification are discussed in the conference paper attached below. The piece is also providing some insight into battery technology progress over recent decades and a conservative forecast. Also please find attached a paper on the technology status of electric energy storage considering the first generation of the propulsion system of the Chevy Volt.

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      ABSTRACT: This publication describes the development of electrified propulsion systems from the invention of the automobile to the present and then provides an outlook on expected technology progress. Vehicle application areas for the various systems are identified based on a range of energy supply chains and the technological limits of electric powertrain components. GM anticipates that vehicle electrification will increase in the future. Battery-electric vehicles will become competitive for some applications, especially intra-urban, short-distance driving. Range-extended electric vehicles provide longer driving range and offer full capability; with this technology, electric vehicles can serve as the prime vehicle for many customers. Hydrogen-powered fuel cell-electric powertrains have potential for application across most of the vehicle segments. They produce zero emissions during all phases of operation, offer short refueling times, but have powertrain cooling and hydrogen storage packaging constraints. While the market share of electrified vehicles is expected to increase significantly, GM expects conventional powertrains with internal combustion engines to also have a long future – however, a lot of them will be supported by various levels of electrification. -- Kurzfassung: Die Entwicklung der elektrischen Fahrzeugantriebe von der Erfindung des Kraftfahrzeugs bis zur Gegenwart wird in dieser Veröffentlichung beschrieben und es wird ein Ausblick auf den zu erwartenden Fortschritt gegeben. Unter Berücksichtigung der Randbedingungen verschiedener Energieketten und technischer Grenzen aller Systemkomponenten eines elektrischen Antriebsstrangs werden sinnvolle Einsatzfelder elektrifizierter Fahrzeugantriebe aufgezeigt. In Zukunft werden die Antriebstränge zunehmend elektrifiziert. In einigen Anwendungen werden batterieelektrische Fahrzeuge wettbewerbsfähig, was besonders für den Einsatz im städtischen Kurzstreckenverkehr gilt. Für solche Anwendungsfälle eignen sich Fahrzeugkonzepte vom Kleinwagen bis zum Stadtbus. Elektrofahrzeuge mit Reichweitenverlängerung erlauben weitere Fahrtstrecken und können somit vollwertige Erstfahrzeuge darstellen. Dadurch wird das Elektrofahrzeug für größere Kundengruppen einsetzbar. Wasserstoffbetriebene Brennstoffzellenfahrzeuge fahren jederzeit ohne lokale Emissionen und lassen sich schnell betanken. Die Anwendung der Brennstoffzellentechnologie ist für die meisten Fahrzeugsegmente sinnvoll und im wesentlichen technisch nur durch die notwendigen Baugrößen der Antriebskühlung und der Wasserstoffspeicher für besonders hohe Anforderungen begrenzt. General Motors ist davon überzeugt, dass der Marktanteil der elektrischen Antriebe signifikant zunehmen wird, geht aber auch davon aus, dass die konventionellen Antriebe mit Verbrennungsmotoren noch eine lange Zukunft haben – wenn auch viele eine Unterstützung durch Hybridisierung erhalten werden.
      Full-text · Conference Paper · Apr 2012

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  • Ulrich Eberle added an answer in Hybrid Vehicles:
    On the design of a hybrid vehicle with electric traction - any thoughts?
    We still live in the era of oil and gasoline powered or diesel powered (or more recently, ethanol powered) cars. We already have idea how should be the next generation of automobiles. But how will be the car for the intermediate phase?
    I think it should be a car with electric traction, with batteries, with a small or micro internal combustion engine only to recharge the batteries.
    I think it could be a car like today's electric cars, equipped with a gasoline engine with maybe 5 hp and a fuel tank with a capacity of perhaps 20 liters. Thus it would be possible to overcome the current limitation of autonomy of electric automobiles.
    This suggestion is not accidentally simple. It is simple because the automotive industry is very slow to introduce effective changes.
    Ulrich Eberle
    Dear colleagues, perhaps the book chapter attached below might be of interest to you. It describes in detail the concept of the extended-range EV, using the Chevrolet Volt and its European cousin, the Opel Ampera, as a specific example. Both the powertrain as well as the battery system and the operating concept are discussed. It would be great if you would consider the piece interesting and helpful. Best Regards Ulrich
    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Vehicle electrification is progressing significantly and is changing the architecture of future cars. This trend is a result of the need for higher vehicle efficiency and the desire to diversify the energy sources used for transportation. Voltec vehicles such as Chevrolet Volt and Opel Ampera are electric vehicles (EVs) with extended driving range. They operate as an EV as long as there is useful energy in the battery. However, unlike a pure battery EV, they do not suffer from lost vehicle utility when the battery is depleted. Volt and Ampera can continue operation by using an internal combustion engine as energy converter. Within the framework of this chapter, in addition to the focus on the current Voltec battery and propulsion system technologies, a brief history of the General Motors EV activities is also provided. ___________ Keywords: Battery, Chevrolet Volt, Opel Ampera, Propulsion system, Voltec.
      Full-text · Chapter · Jan 2014