Ensuring Safety and Business Models for Lithium Ion Batteries

Transcription

1 Technology Report Ensuring Safety and Business Models for Lithium Ion Batteries Dr. Noboru Sato Executive Adviser, ESPEC CORP. Visiting Professor, Green Mobility Collaborative Research Center, Nagoya University Abstract Business models in the lithium-ion battery (LIB) industry differ significantly between small consumer batteries, in-vehicle batteries, and fixed batteries, and it is thought that businesses must have detailed strategies based on an understanding of the differing nature of these various models if they are to increase competitiveness. In particular, competition related to technology development and business models for in-vehicle LIBs has been gradually intensifying on a global scale. This report provides commentary on related market trends, business models, and ensuring reliability and safety.

2 Technology Report Ensuring Safety and Business Models for Lithium Ion Batteries Dr. Noboru Sato Executive Adviser, ESPEC CORP. Visiting Professor, Green Mobility Collaborative Research Center, Nagoya University 1. Market trends surrounding lithium-ion batteries In 1991, Sony became the first manufacturer in the world to mass produce lithium-ion batteries (LIBs). The LIB business has since been overwhelmingly dominated by Japanese manufacturers, but our position at the top has been threatened from the mid-2000s onwards. It is now 23 years since Sony established its LIB business, and the firm's announcement in the second half of 2012 that it was going to sell off its battery business sent shockwaves through the industry. Sony's announcement is indicative of the extent to which the Japanese consumer LIB industry has lost competitiveness. Even Sanyo, which was the industry leader at the time, has been absorbed by Panasonic, but there is a feeling that even Panasonic itself has been unable to come up with the winning formula (Fig. 1). 10 items in which first position has changed 12 items for which Japan is No. 1 worldwide Item 1st position 2nd position Item 1st position 2nd position Increased sales in prominent markets Products with high level of bulit-in quality and coordinated design Toyota Motor Corporation Toyota Motor Corporation General Motors (USA) Automobiles (Japan) Automobiles (Japan) General Motors (USA) 11.7 (1.7) 11.2 (-0.2) 11.7 (1.7) 11.2 (-0.2) Yingli Green Energy Holding First Solar (USA) Solar cells (China) Video cameras Sony JVC Kenwood 7.2 (1.2) 5.6 (-1.7) 44.0 (0.0) 18.0 (3.0) Wind power generators Washing machines GE Wind Energy (USA) Vestas (Denmark) Canon Nikon Digital cameras 15.5 (6.8) 14.0 (1.1) 22.6 (3.8) 20.9 (5.4) Haier (China) Whirlpool (USA) Nintendo Sony Computer Entertainment Video game consoles 12.4 (1.0) 12.2 (-0.1) 41.4 (0.1) 41.1 (2.2) Product competitiveness increasing High function materials and components Lithium ion batteries Samsung SDI (South Korea) Panasonic (Japan) Toray Toho Tenax Carbon fiber 25.1 (1.9) 20.7 (-2.8) 20.9 (0.4) 16.7 (0.3) Samsung Electronics (South Samsung Electronics (South Nokia (Finland) Nichia Corporation Cellular phone handsets Korea) White LEDs Korea) 23.5 (4.2) 19.3 (-5.0) 33.1 (0.8) 10.8 (-7.4) Samsung Electronics (South LG Display (South Korea) LCD panels Korea) CMOS image sensors Sony OmniVision Technologies (USA) 24.6 (2.5) 20.1 (-2.6) 32.1 (0.4) 14.4 (3.7) Performance in depressed markets Renesas Electronics Freescale Semiconductor (USA) Microcomputers Mitsui O.S.K. Lines (Japan) Fredriksen Group (Norway) 25.6 (-1.3) 9.4 (-0.1) Crude oil shipments 5.9 (-0.2) 5.5 (-0.8) Facilities and services supporting manufacturing Semiconductor fabrication Applied Materials (USA) ASML (Netherlands) Toyota Industries Corporation KION (Germany) Industrial vehicles systems 14.4 (1.5) 12.8 (-2.1) 19.1 (0.9) 15.0 (0.2) HDD Western Digital (USA) Seagate Technology (USA) FANUC ABB (Switzerland) Articulated robots 44.6 (14.1) 41.9 (10.1) 27.3 (-1.1) 23.4 (3.2) Mitsui O.S.K. Lines Fredriksen Group (Norway) Crude oil shipments *Figures indicate percentage share of market. Figures rounded up to first decimal place. Figures in 5.9 (-0.2) 5.5 (-0.8) parentheses indicate percentage point change from previous year. NYK Line EUKOR (South Korea) Automobile shipments 16.3 (-1.5) 13.5 (0.4) *Figures indicate percentage share of market. Figures rounded up to first decimal place. Figures in parentheses indicate percentage point change from previous year. Fig. 1 - Changes in global market share (The Nikkei, July 1, 2013)

3 In addition to these developments, Chinese batteries have been putting pressure on Japan's share of the premium market segment (volume zone) for low-end products. For example, Apple employs LIBs made by Chinese firm ATL in the iphone and the ipad, indicating that Chinese products have achieved a certain level of recognition. While Chinese batteries compare unfavorably to Japanese and South Korean products in terms of reliability, they are starting to earn a good reputation in terms of overall performance including price. There is a need to objectively and systematically examine the relative loss of competitiveness suffered by Japan's LIB industry for small consumer products. Based on my experience at Samsung SDI, I think that the causes behind this loss can be organized as shown in Fig. 2 *1. Fig. 2 - Factors behind decrease in competitiveness suffered by Japanese LIB industry On the other hand, the strength of Japanese battery manufacturers is being demonstrated in in-vehicle batteries. One of the topics currently of most concern to the automotive industry is the issue of vehicle electrification such as hybrids (HEVs), plug-in hybrids (PHEVs), electric vehicles (EVs), and fuel cell vehicles (FCEVs). These environmentally friendly vehicles look set to change the competitive landscape of the automotive industry. Japan is a leader in the field of vehicle electrification, and because this field is driven by high specifications, the high reliability of Japanese in-vehicle batteries would be advantageous. By contrast, the battery industry is weak in Europe and the United States. The name to watch in the in-vehicle battery market is South Korea's LG Chem. LG Chem has been strengthening its business ties with Hyundai, GM, and Renault. Samsung SDI has business partnerships with BMW and Chrysler. However, neither company has been able to collaborate with EVs, HEVs, or PHEVs developed by Japanese automakers.

4 A feature of the Japanese market is that automakers and battery manufacturers have established specialized battery manufacturers through joint ventures. Automakers want to get a deeper understanding of battery tecnologies and features, which is necessary also in order to reduce costs. For their part, battery manufacturers gain an understanding of how batteries are used in vehicles, and reflect this in product development. Such cooperative relationships allow both parties to realize each other's ideas by making compromises. This is a feature that is lacking in the European and US industries, which have different product development cultures. It looks certain that Japan will continue to be a driving force in the vehicle electrification. Japan is also a strong performer in the fields of power semiconductors and power electronics as a whole. Power device products including batteries will continue to be the core of the Japanese industry in the years to come. 2. Business models for in-vehicle LIBs 2.1 Shift from EVs to HEVs, and battery development In 1997 Toyota released the world's first HEV, the Prius, and was followed two years later by Honda, which released the Insight in The technology cultivated in EVs was clearly applied to vehicle and battery technology in HEVs, and the two firms attained overwhelming strength in HEV intellectual property rights. The Strategic Market Creation Plan, which was prepared as part of the Japan Revitalization Strategy announced in June 2013, sets targets related to next-generation vehicles (EVs, HEVs, PHEVs, FCVs, and CNGVs). The plan calls for such vehicles to account for 50 to 70 percent of new vehicle sales by Fig. 3 shows one aspect of the Chinese market in 2013, where the situation with regard to fine particle (PM2.5) counts as well as air pollution is extremely serious. In light of this state of affairs, the Chinese government has introduced environmental regulations. Alongside the US's ZEV regulations and Europe's CO 2 regulations, more stringent environmental regulations such as China's CO 2 regulations are acting as a driving force behind the development of next-generation vehicles. Fig. 3 - Worsening air pollution in Zhengzhou, China, and draft regulations

5 2.2 Business initiatives by battery industry firms Some firms such as Mitsubishi Heavy Industries (MHI) have pulled out of the battery business altogether. Despite having spent around 10 billion yen on completing battery production facilities at its Nagasaki Shipyard & Machinery Works in 2010, MHI withdrew as a regular member of the Battery Association of Japan in March 2014, and plans to sell the business to a Taiwanese firm. The business has production capabilities of 66,000 kwh and can manufacture 400,000 mid-size, 185 Wh-class cells annually. Although MHI had invested heavily in LIBs for EVs, the sale of the business was triggered by lackluster sales of EVs themselves. Meanwhile, as evidenced by the example of startups like US firms EnerDel and A123 Systems, both of which failed in 2012, survival in the battery industry is not easy. A123 Systems was bought by China's Wanxiang Group for around 25 billion yen, and has now transformed itself into a Chinese firm. Generally speaking, one factor behind the demise of these firms is the large number of battery manufacturers around the world, but in the end, the key to success lies in overall competitiveness in terms of performance, price, reliability, and safety. Amidst all this, NEC has decided to buy Wanxiang's large-capacity energy storage systems business targeting power companies for around 10 billion yen. According to NEC, the global market for large-scale energy storage systems looks set to grow to 600 billion yen by It would appear that NEC took its recent decision in response to this prediction. Eying the expansion of vehicle electrification in China, Samsung SDI has built a new factory in Xian, which is expected to be operational from The firm will base its business model on the existence of a Samsung Electronics smartphone manufacturing plant in Vietnam. This move has been taken in response to the Chinese government's strategy to rapidly expand the vehicle electrification, and is the result of significant consideration of the scale of the market. In April 2014, Samsung SDI established a joint venture with a Chinese auto parts maker, Anqing Ring New Group, and at some stage during the year plans to start construction of a new factory, which is expected to be operational in The new business will operate in a site adjacent to a Samsung Electronics semiconductor factory. Although Samsung SDI and Bosch established a joint venture in 2008, the business was dissolved in September 2012 due to differences in opinion between the two firms. Meanwhile, Lithium Energy and Power, a joint venture between Bosch and GS Yuasa started in Maintaining reliability and ensuring safety of in-vehicle LIBs 3.1 Development of components and creation of technologies to ensure LIB safety 2) Recently in China, the number of chemical engineering papers related to batteries has increased, and more and more effort is also being put into research and development. While Japan is a leader when it comes to cutting-edge research, its market share will change unless material manufacturers are able to come up with ways to reduce costs associated with low-end products. Behind this situation lies the fact that South Korean material manufacturers have improved their technical capabilities and enhanced their cost competitiveness in conjunction with the gains made by LIB manufacturers. Under such circumstances, maintaining and improving the cost competitiveness of Japanese materials and components going forward will require (1) the acceleration of cutting-edge technologies to further enhance high-end materials, (2) research and development activities aimed at discovering how to achieve low costs in the premium market segment (volume zone) for low-end products, and (3) strong growth strategies involving partnerships with LIB manufacturers. Approaches related to LIB safety are influenced significantly by materials used, particularly the

6 chemical structure of positive electrode materials. An easy-to-understand example of battery safety is presented in Fig. 4. In the case of LiNiO 2, which forms a layered structure, because lithium moves toward the negative electrode as the charge state continues, it breaks away from the positive layers. If charging continues until the battery is overcharged, depending on the circumstances in which the lithium has broken away, a breakdown in crystal structure occurs. As an extreme example, if we consider a scenario in which the lithium moves completely to the negative electrode, the eventual crystal structure of the positive electrode will be NiO 2. This material cannot exist stably. If we try to stabilize it, an excess of oxygen occurs and the material releases surplus oxygen. Fig. 4 - Differences in safety stemming from differences in crystal structure of positive electrode Eventually, there is a mechanism whereby the surplus oxygen that is released reacts with electrolyte components and the battery enters combustion mode. Accordingly, it is necessary to design positive electrode materials carefully depending on the application. When considered from a similar point of view, it is also possible to explain the stability of manganese spinel LiMn 2 O 4 on the right side of the Fig.4. Even if the battery was overcharged continuously and the lithium moved to the negative electrode, the crystal structure ultimately remaining would be Mn 2 O 4, or manganese dioxide, making it chemically stable. While LiNiO 2 provides more power per unit mass, its poor chemical stability makes it difficult to apply to large LIBs such as in-vehicle batteries and fixed batteries. In contrast, while manganese spinel LiMn 2 O 4 does not provide as much power per unit mass, its excellent safety properties mean that it is often applied to large LIBs. The LIB manufacturing process consists of multiple processes including mixing of active materials, conductive materials, and additives; coating of aluminum and copper foil on current collectors; rolling; drying; winding; and aging. These processes share the same technological domain as various painting processes. Settings and factors that need to be managed in these processes are wide-ranging and include controlling particle size in active materials, managing coating thickness, and ensuring uniform drying conditions. The automation of processes to prevent contamination by foreign matter is also quite advanced. Contamination by foreign substances is a dangerous factor that inhibits safety, and is an aspect of process

7 management to which utmost care should be paid during the electrode manufacturing process. For this reason, many manufacturers employ systems that attract foreign matter by installing powerful magnets in the process. Moreover, the addition of a binder to the active material produces functions that improve the efficiency of the electrochemical reaction and control the degradation itself of the active materials. Thanks to such advantages, binders are right on the verge of establishing a position as a functional material. For example, it has been confirmed that manganese can leach out into the electrolyte and cause deterioration if manganese spinel is applied to the positive electrode, but technology has also been developed that inhibits deterioration by applying an appropriate binder. Until now, positive electrode materials that are expected to increase power and output by achieving high voltages have been OLO, an over-lithiated positive electrode material, and 5V LMO active materials (Fig. 5). Fig. 5 - Chemical structure and thermal stability of LMO positive electrode materials However, while these materials are promising, there are problems with the decomposition voltage of electrolyte components, and practical applications will not be realized unless there is coordinated development of technology to improve the decomposition voltage of the electrolyte. Because such materials are unfavorable in terms of safety, ensuring reliability and safety is a significant challenge. Similarly, new silicon oxide materials are in the process of replacing conventional carbon materials, particularly graphite, in negative electrodes. However, it has not yet reached the point where it is possible to replace all graphite negative electrodes with silicon oxide negative electrodes, and a mixture of graphite and silicon oxides is still used. This is because although the silicon oxide structure is capable of absorbing sufficient amounts of lithium during lithium intercalation to provide a large power capacity, it is placed under load by the expansion and contraction of the electrode during charging and discharging. If the volume of the structure expands too much, capacity deteriorates and battery life is shortened. When originally commercialized by Hitachi Maxell in 2010, silicon accounted for 3 percent of the negative electrode, while the remaining 97 percent was graphite. Since then the ratio of silicon oxides has increased and now accounts for around 7 to 10 percent. A focus of development activities going forward will be to investigate the extent to which the percentage of silicon oxides can be increased. Ensuring reliability and safety is a challenge when applying such materials to in-vehicle LIBs and increasing the ratio of silicon metal oxides. At any rate, the key to the development of new materials lies with Japan's chemical material manufacturers. These companies are a big presence in the industry, with firms like Shin-Etsu Chemical

8 producing silicon oxides and Mitsubishi Chemical Corporation producing general component materials. US firms 3M and DuPont are also promoting materials development, but have not quite been able to make inroads into the business. Both companies have high technical potential, but both are also affected by the lack of a battery industry in the U.S. to give them traction. As Japanese materials manufacturers already understand the specifications that battery manufacturers require, and have development activities that are focused several years into the future, it is hard for other firms to enter the industry. In light of these considerations, there is a high probability that any new materials developed in the future will originate from Japan. Research is conducted by a variety of parties throughout the country including the private sector, universities, public research institutes, and national projects managed by NEDO. No other country is undertaking such comprehensive efforts as Japan, and in this sense, the future looks promising. 3.2 Development process for ensuring safety technologies When all is said and done, increasing the durability, reliability, and safety of batteries is an essential part of technology development. This is because automobile manufacturers have caused automotive accidents attributable to batteries, and ensuring safety in the future is the industry's most pressing challenge. The conceptual process of evaluation test items that are required before a technology is applied to in-vehicle batteries is shown in Fig. 6. The manufacturer must be able to adequately ascertain the suitability of a given technology for use in battery pack systems. This area is also extremely important when it comes to the relationship between automakers and battery manufacturers because any kind of omissions can lead to defects or accidents. In Japanese product development culture, automakers and battery manufacturers both employ a cooperative working style so that such omissions do not happen. Evaluation steps required before product can be used as in-vehicle battery Fig. 6 - Development process for ensuring battery safety

9 There has been discussion from time to time regarding the development of international standards for in-vehicle storage batteries, and amongst such standards battery safety evaluations and criteria are especially important. These standards apply in particular to immersion tests, crush tests, vibration tests, impact tests, and battery life test methods, and cover a wide range of fields if charging systems and the like are included. Fig. 7 indicates evaluation modes used for finished vehicles. The figure shows safety and reliability validation tests, but all conceivable evaluation methods must be introduced and substantiated. (a) Immersion test (b) Impact test Fig. 7 - Validation of EV safety and reliability (From AESC and Nissan's AABC Asia 2014 proceedings) Processes aimed at reducing the burden of evaluation on automakers, and business models involving these processes will be effective. A variety of such businesses can be envisioned. For example, cases where automakers directly conduct evaluations and produce results in evaluation facilities that they have installed themselves; cases where automakers obtain results and reduce costs in terms of time and manpower by outsourcing evaluation work to companies that have evaluation outsourcing functions such as ESPEC; or cases where outsourcing firms provide particular automakers and battery manufacturers with laboratory functions, thus providing outsourcers with a place they can use as though it were their own laboratory. Because automakers that are proactively promoting vehicle electrification by expanding the range of models under development have to deal with an increasing number of battery types, the aforementioned business models are effective for both parties. At the same time, automakers for whom it is not easy to roll out evaluation facilities can improve the efficiency of product development through the proactive use of outsourcing firms. In addition to the obvious time improvements, ESPEC is able to offer solutions that go the extra mile,

10 for example, by providing know-how concerning evaluation methods and by identifying and making proposals regarding technical challenges related to evaluation results. Accordingly, it is hoped that this kind of new business model will be rolled out in the future. One point that also applies to the battery industry as a whole is that when considering the possibility of collaborating with many automakers, the same kind of thing can be said due to the fact that the specifications of each automaker differ. Going forward it is hoped that the building of relationships and collaboration between outsourcers and outsourcing firms will become a trigger that improves the competitiveness in the development of in-vehicle secondary batteries. In November 2013, ESPEC established the Energy Device Environmental Test Center in Utsunomiya. The center allows ESPEC to provide customers with a true full-scale outsourcing business that contributes to the development of the automotive and battery industries. As indicated in Fig. 8, the Toyota, Kariya, and Kobe test centers also provide similar functions. Fig. 8 - ESPEC's test centers and evaluation systems ESPEC's Energy Device Environmental Test Center is home to the world's first external short circuit testing system for battery packs. Furthermore, with the development of a three-chamber charge/discharge evaluation test system, ESPEC has released a product that is capable of performing efficient evaluations based on desired temperature conditions and load modes. A satellite map of industries involved in research into innovative in-vehicle batteries is shown in Fig. 9. Powerful development capabilities can be created by pulling together satellite industries that provide efficient basic research, material and components development, battery development, and evaluation and analysis outsourcing functions. This unique cooperative style is unheard of in other countries.

11 Fig. 9 - Forces driving the development of innovative in-vehicle batteries from research to commercialization Conclusion Business models in the LIB industry differ significantly between small consumer batteries, in-vehicle batteries, and fixed batteries, and businesses must have detailed strategies based on an understanding of the differing nature of these various models if they are to increase competitiveness. In particular, competition related to technology development and business models for in-vehicle LIBs is intensifying on a global scale. Aside from being an issue of worldwide importance, vehicle electrification presents a chance not only for the automotive industry, but also for research organizations and the battery, materials and components, and evaluation test industries. Compared to other types of batteries, the most challenging aspect of product development for in-vehicle batteries is ensuring safety and reliability. Currently, in light of the fact that there has been increased activity towards providing international standards for safety evaluation tests a field in which many countries have seized the initiative, the automotive industry is intent on developing technologies to fulfill various test methods while the battery industry is intent on creating strategies and tactics for winning business with the automotive industry. Bibliography 1. Sato, N., Nikkei Business Online, "Technology Management", serial starting April 19, Sato, N., Yoshino, A. (Editor), "Safety Technologies and Materials for Lithium-ion Batteries", CMC Publishing, p. 247 (2009)