170 years ago, Faraday appreciated the different electrical properties of nano gold over bulk metal in electrical devices, so applying nanotechnology to these things is scarcely new. However, the huge sums now being applied to improvement of lithium traction batteries in particular are now leading to work on a much larger scale and thin film technology, nanotechnology and printing are an increasingly important part of this.
Potential is considerable. LG of Korea, one of the leaders in traction batteries, forecasts 4.6 million electric cars produced in 2015 and IDTechEx forecasts 3.8 million for that year - hybrid and pure electric.
The conference "Lithium Battery Technology and System Development" in London 9 March 2010 was concerned with "breaking barriers for electric vehicles". Professor John Owen of the School of Chemistry at the University of Southampton in the UK described work on interdigitated laminar electrodes to overcome the problems of ionic and polymeric electrolytes that are resistive. His team is involved in a pan European project working on this and involves Swedish, Dutch and French organisations, Varta Battery and St Jude Medical.
Importance of iron, manganese and phosphorous
Dr James Myners, who has recently sold his Lithium battery electrode business in Switzerland to Dow Chemical, reported on that company's effort and gave his take on progress. Interestingly, he pointed out the widespread abundance of lithium - current reserves can power one billion cars - and the fact that the lithium is only about one percent of the cost of a lithium electric car battery.
Cobalt may have a supply problem however - perhaps another reason to move to the more affordable and - many say - chemically safer manganese formulations (e.g. with phosphorous and/or iron). He said that the more exotic options such as Zn-air, LiS and Li-air will appear in laptops and mobile phones before cars.
Johnson Controls-SAFT
Dr Christian Rosenkranz, EUROBAT representative and Director of Global business & EU Government Affairs - Johnson Controls SAFT Advanced Power Solutions GmbH claimed that only SAFT, with its military work, has actually demonstrated life of over ten years for lithium batteries because the others have not been in the business long enough.
JC-Saft has had great success in gaining a lion's share of the Obama battery investment and it expects to be price competitive with East Asian factories making these traction batteries as it brings on its facilities in Holland and the USA at an initial cost of $600 million. JC-Saft does not take the popularly narrow view so often encountered in the West that the opportunity ends with cars.
Ribbon batteries?
Various other speakers described experience integrating traction batteries and gave the trends. For example cylindrical wound cells can be good for high power in hybrids and prism construction is used for high energy as with pure EVs but pouch constructions still have a place.
At a later stage, battery ribbon printed reel to reel and placed across the surface of the car may give faster charge-discharge, lower cost and better temperature control leading to longer life. It may also save space and weight. It is interesting that Planar Energy Devices, set up in the USA to make laminar batteries, is now targeting traction.
Varied applications
LiFeBATT described how its five personnel are supplied with LiFePO batteries from Taiwan and these will be fitted on 10,000 vehicles in 2011 including military ones. It is niche marketing. For example, it is involved in a Dutch built marine hybrid. Like ReVolt Technologies and the East Asians, JC-Saft sees considerable potential in the 24 million e-bikes being sold yearly and many e-scooters and e-motorbikes are coming along often with a motor on each wheel and regenerative braking.
However, the retail price of some e-bikes in China, where 95% of them are purchased, can be as low as $150. At the other extreme, several speakers noted rapid adoption in buses and commercial vehicles with 200KW and 10-80kWh being typical specifications.
One aside was that the newer lithium batteries will mean that supercapacitors (also thin film and printed technology) are no longer needed to manage fast discharge and charge but, with supercapacitors coming along with several times improved parameters, that is not certain.
Indeed some buses recharge using supercapacitors whenever they stop to pick up passengers and there are some large vehicles that have supercapacitors and no battery.
Market value
The value of the traction battery market now exceeds that of other lithium batteries: one car traction battery is equivalent to 10,000 mobile phone batteries and the gap is widening. Whereas lithium battery output in China roughly matches expected demand, in Europe it is half and in Japan/Korea it is 40 times the expected demand for traction batteries.
Capacity in the USA is also well in excess of expected demand so there will be global overcapacity and a shakeout of major suppliers with no more than six succeeding. Of the leading contestants, several are now investing their second billion dollars to achieve the necessary one billion dollars of yearly traction battery sales that are necessary to be viable in the long term.
Panasonic, now owner of Sanyo, is leader since it also has a traction battery joint venture with Toyota, the global leader in hybrids. JC-Saft is unusual in having supply agreements with Azure for commercial vehicles, and Mercedes, BMW and Ford for cars.
An SMMT study has recently shown that the Chinese are not serious competition in electric cars in the near term. Only a few hundred Prius cars, the world's best selling hybrid, sell yearly in China so far.
Importance of electronics
With over-engineering of traction batteries for safety reasons being common practice, according to the conference speakers, it is interesting that the electronics is now a major part of the cost. There is scope for printing both battery parts and associated electronics to reduce size and cost and improve performance. For example, Sharp Laboratories of America is involved in this.
IDTechEx notes that T-ink is making multilayer, printed, conductive patterning a replacement for ceiling-located car control units, saving space, cost and weight and there is work on putting conformal, transparent, photovoltaic film over the whole surface of a car. Indeed, we have transparent flexible laminar electronics coming along thanks to Fraunhofer ISC, the University of Cambridge and others. Transparent organic photovoltaics being developed by Korea Institute of Materials Science, the Institute of Materials Research and Engineering Singapore, CSIRO Australia and Dyesol Australia needs better barrier layers for longer life but these are being developed by DELO Industrial Adhesives Germany, 3M Display and Graphics Business Lab USA and others presenting at Printed Electronics Europe in April.
For more attend Printed Electronics Europe 2010.