Sometimes the small conferences are the best. The International Electromobility Conference and Exhibition for Electromobility is currently taking place in beautiful Ljubljana in Slovenia with about 100 people initially in attendance. Mitsubishi Motors MiEVs, Renault and other PEV cars are on display.
Slovenia is sandwiched between Austria and Croatia. The capital Ljubljana has a population of one third of a million and a large university with 60,000 students served by a budget one third of the amount per head that is the average for Europe. The rest of the two million Slovenian population is wandering lost in the forests of this, the third most forested European country after Finland then Sweden.
Jean Marie Tarascon, of the delightfully named Universite Picardie Jules Verne in Amiens France, started the next conference session by describing his attempts to improve Li-ion batteries. He noted that there are 80-100 years of lithium reserves already identified in the world. Sodium vanadium and sodium titanium based cathodes may follow. In the meantime, lithium iron cathodes in lithium-ion batteries are the ones to beat because they use low cost materials and have improved temperature performance and therefore safety.
Energy density needs to improve. 150 Wh/kg is one fifteenth of gasoline. He develops relatively low temperature ionothermal nano processes to improve on lithium iron phosphate cathodes for lithium-ion rechargeable batteries by creating lithium iron sulphate fluoride in nano form. Biomimetic approaches to replacing inorganic with organic Li2C6O6 cathodes from biomass and sunshine were also studied but they have poor performance as yet. LiS at theoretical 2567 Wh/kg and Li air at 3582 Wh/kg are candidates. They give a practical proposition of three times improvement but better electrolytes are needed for Li air which is a long way off.
The next presentation from Josh Thomas of Angstrom Advanced Battery Centre Uppsala University Sweden and Battery Management Systems BMS spinoff Electroengine, standing in for Massachusetts Institute of Technology, noted that highly charged electrolytes are more prone to oxygen release, burning up cathodes. Yet he rehearsed the need for lithium ion batteries of higher energy density both in cars and in the smart grid linked to cars. LiCoO2 cathodes are 36% of battery cost and therefore the first target since the cathode also primarily controls life, power and energy density and safety as well - all aspects that need to improve. Lithium iron silicates are being considered with doping nano coating and nano sizing.
Currently, similar energy density but lower cost and better stability and safety are in prospect. Incorporating manganese as well may lead to higher cell voltage and energy density. Low cost microwave processing was studied but this turns out to be more appropriate for supercapacitors. Combustion synthesis is now preferred. A 50% excess of sucrose gives best power density so far. Interdigitation biomimetics can help more. Solid Electrolyte Interphase SEI layer problems lead to unpredictability so far. He also discussed the need for better BMS and progress towards them.
In the coffee break we saw the impressive in-wheel motor for the Smart car developed by local company Elaphe. At 19kg, It is half the weight of others yet it has more power at 30kW, they claim. It uses much less of the expensive neodymium magnet material so costs will be unusually low despite the fact that this is a conventional synchronous motor not a pancake motor.
Next came Dr Anna Teyssot of Renault who noted that over 16,000 Nissan Leaf cars have been sold this year, largely because of progress with batteries, the topic of her presentation. Of course, Nissan is a partner of Renault. They admit that you cannot afford to replace the battery in a pure electric on-road car so their answer is rental. In development, $150/kWh is the target for Li-ion battery development to 2020 in Europe.
They seek as good or better safety than conventional cars. That is really a battery and BMS issue. Emissions and other aspects were also covered. In answer to questions, she said that they are not wholly committed to pure electric cars to the exclusion of hybrids because they are developing mild hybrids but they do see a larger percentage market share in Europe for pure electric cars because "only in Europe are there lots of diesel cars competing well with hybrids." It was not clear to us how this could increase the addressable market for pure electric cars.
Professor Doron Aurbach of Tel Aviv University Israel returned to the subject of materials for advance Li-ion traction batteries. He studies layered, olivine and spinel lithium manganese oxide spinel and lithium iron phosphate but only the latter works at minus 40 degrees Celsius. However Li metal O structures in an inactive LiMnO2 host and using metals such as NiMnCo together show promise. He liked lithium titanium oxide spinel anodes because of higher voltage, greater stability etc. and Chemical Vapour Deposition CVD silicon nanowires and elaborated electrolyte interaction. Finally he covered LiS chemistries with lithium nitirite electrolyte additive, activated carbon cloth in the cathode and amorphous silicon in the anode look promising to give adequate life. 40-60% improvement in energy density of Li-ion batteries is in prospect in these various ways including Al- ion batteries with chemical range extension. He warned that one big accident can put the industry back for another century.
Wolfram Munch of EnBW, the power utility in Baden Wurttemburg ended the morning with a talk on power plants, renewables, grids - towards the smart energy world. With some six million customers and more than 20,000 employees, EnBW Energie Baden-Württemberg AG generated annual revenue in excess of € 17 billion in 2010. In Germany there is no problem of energy production if even 10% of all cars become pure electric, something not in prospect for the next ten years. However, there would be problems of power delivery without power shifting - smart metering and so on. The hydrogen economy interests Germany as it has long experience and capability in hydrogen distribution and storage but infrastructure for cars and hydrogen burning cars - nowadays meaning fuel cells - are not available, "but that may be about to change". In the future, the use of hydrogen in place of natural gas in the home may return in Germany, progressing the carbonless economy, but economics do not look good. Both integrating electric vehicles into the grid system and increasing the share of renewable energy in the production of power in Germany are economic not technical challenges now. A regulatory framework for smart grids does not yet exist in Germany.
Professor Andreas Friedrich of DLR Germany described the possible use of fuel cells in aircraft. In principle, they can replace the Auxiliary Power Unit APU and emergency power supplies and his team have demonstrated making an airliner into an electric vehicle when on the ground by electrifying the nose wheel. Many secondary benefits accrue such as the fuel cell providing cabin water and humidity and providing depleted air to the existing fuel storage compartment. However, we understand that the necessary hydrogen storage is a deterrent to aircraft manufacturers. Herr Friedrich said that all fuel cells need hybridisation with batteries in the foreseeable future and these lithium- ion batteries are not liked by their partner Airbus. We note that spontaneous combustion of lithium battery cargo caused a fatal crash of a FedEx aircraft not long ago.
Bernard Lestriez of IMN gave a thorough analysis of Lithium-ion cathode optimisation. Slurry stability and electrode homogeneity, reproduceability and performance need improvement with critical dependence on nanoscale . He warned that ultra thin adsorbed polymers do not have bulk properties.
Dragana Jugovic of the Institute of Technical Sciences, Serbian Academy of Science and Arts described work to optimise olivine lithium iron phosphate powders used in the production of lithium-ion traction batteries. Ultrasonic spray pyrolysis and sonochemical activation were tried, for example. Aqueous precipitation in molten stearic acid was best and many morphologies etc are possible. Prof Gunther Wittstock of Oldenberg University in Germany addressed local analysis of catalytic reactions in electrochemical energy conversion and energy storage devices. In a parallel session, hydrogen refuelling stations, automatic measuring infrastructure and smart grid integration were addressed. This focussed on uses for Scanning Electron Chemical Microscopy SECM.
For more attend Electric Vehicles Land, Sea & Air 2012 where a large number of electric vehicle manufacturers not seen in conventional EV events will present including WheelTug aircraft electrification, MotoVolta, LLC motorbikes, SolTrac farm tractors, Monterey Bay Aquarium Research Institute Autonomous Underwater Vehicles AUVs and manufacturers of industrial, commercial, military, e-bike, cars and other EVs.