How is the development status of lithium titanate battery technology at home and abroad?

　　Internationally leading companies in the research and industrialization of lithium titanate materials include the American Ao Titanium Nano Technology Company, Japan's Ishihara Industry Co., Ltd., and the British Johnson Matthey Corporation.

　　Since the industrialization of lithium-ion batteries in 1991, the negative electrode material of the battery has been dominated by graphite. Lithium titanate, as a new type of lithium-ion battery's negative electrode material, has received attention due to its many excellent properties since the late 1990s. For example, the crystal structure of lithium titanate materials can maintain a high degree of stability during the inlay and deintercalation process of lithium ions, and the lattice constant changes very little (volume change

　　This "zero strain" electrode material greatly extends the cycle life of lithium titanate batteries. Lithium titanate has a three-dimensional lithium ion diffusion channel unique to the spinel structure, and has the advantages of excellent power characteristics and good high and low temperature performance. Compared with carbon anode materials, the potential of lithium titanate is higher (1.55V higher than that of lithium metal), which results in that the solid-liquid layer that usually grows on the surface of electrolyte and carbon anode is basically not formed on the surface of lithium titanate. .

　　More importantly, it is difficult to generate lithium dendrites on the surface of lithium titanate within the voltage range of normal battery use. This largely eliminates the possibility of a short circuit formed by lithium dendrites inside the battery. Therefore, the safety of lithium-ion batteries with lithium titanate as the negative electrode is the safest among all types of lithium-ion batteries that I have seen so far.

　　Most people in the industry have heard that lithium titanate replaces graphite as the negative electrode material of lithium batteries with a cycle life of tens of thousands of times, which is much higher than the common traditional lithium-ion battery, and it will die after only a few thousand cycles.

　　Because most professional lithium battery professionals have never actually made lithium titanate battery products, or have just done it a few times and have encountered difficulties and ended up in a hurry. So they couldn't calm down and think carefully, why most of the perfect traditional lithium-ion batteries can only complete 1000 to 2000 charge and discharge cycle life?

　　Does the fundamental reason for the short cycle life of traditional lithium-ion batteries stem from one of the basic components-graphite anodes that are overwhelmed? Once the graphite anodes are replaced with spinel-type lithium titanate anodes, the same lithium-ion battery chemistry is basically the same The system can be recycled to tens of thousands or even hundreds of thousands of times.

　　In addition, when many people talk about the low energy density of lithium titanate batteries, they ignore a simple and important fact: that is the long cycle life, extraordinary safety, and superiority of lithium titanate batteries. Power characteristics and good economy. These characteristics will be an important cornerstone for the large-scale lithium energy storage industry that is currently emerging.

　　In the past 10 years, research on lithium titanate battery technology at home and abroad can be described as turbulent. Its industrial chain can be divided into the preparation of lithium titanate materials, the integration of lithium titanate battery production and lithium titanate battery systems, and their applications in the electric vehicle and energy storage markets.

　　1. Lithium titanate material

　　Internationally leading companies in the research and industrialization of lithium titanate materials include the American Ao Titanium Nano Technology Company, Japan's Ishihara Industry Co., Ltd., and the British Johnson Matthey Corporation. Among them, the lithium titanate material produced by the United States Austrian Titanium has excellent performance in terms of rate, safety, long life, high and low temperature. However, the production cost is too high due to the excessively lengthy and detailed production method, which makes it difficult to commercialize.

　　Ishihara Industries is one of the largest titanium dioxide manufacturers in Asia. The company has production bases in Japan, Singapore, and Taiwan. Ishihara Industry has made full use of its abundant raw material resources and successfully developed a variety of low-cost, high-rate, and different particle size lithium titanate products by wet process. Products with similar performance have a greater advantage in price compared to the American Aoti's lithium titanate materials, but they are slightly inferior to Chinese domestic products. Johnson Matthey has taken over materials such as lithium iron phosphate owned by the former German Southern Chemical Company, but has insufficient investment in the development and production of lithium titanate materials, and the product quality is difficult to stabilize.

　　There have been many domestic mass production of lithium titanate materials, such as Xingneng New Materials Co., Ltd., Zhuhai Yinlong New Energy Co., Ltd., Huzhou Weihong Power Co., Ltd., Shenzhen Beiterui New Energy Materials Co., Ltd., Hunan Shan Shan New Materials Co., Ltd. and many smaller lithium titanate manufacturers around Shenzhen.

　　Xingneng is a manufacturer specializing in the production of lithium titanate materials, with an annual production capacity of 3000t. The lithium titanate production process has customer adaptability and stability. It can be flexibly adjusted without changing the existing production lines and equipment to produce suitable products. Lithium titanate required by customers, and to maintain the stability of product technical indicators. Relying on the upstream lithium ore and titanium ore resources, Xingneng can realize the coordinated production from raw ore to final materials, which can realize the performance improvement and cost reduction of lithium titanate products, and avoid the impact of fluctuations in the raw material market.

　　In 2011, Zhuhai Yinlong completed the acquisition of 53.6% of the shares of the American Austrian Titanium Nanotechnology Company, thus becoming one of the few companies in China that simultaneously possesses lithium titanate material preparation, battery production, lithium titanate electric vehicles, energy storage systems, and frequency modulation. It has a number of core technologies and more than 30 patents for peak shaving and other applications.

　　At present, Northern Austrian Titanium Nanotechnology Co., Ltd. ("Northern Austrian Titanium") has an annual production capacity of 100t of lithium titanate materials and provides high-quality nano-level lithium titanate for Northern Austrian Titanium and Zhuhai Yinlong. Zhuhai Yinlong New Energy has also carried out a strategic cooperation with Ishihara Industry on the research and development of new lithium titanate materials. The cost of the materials will decrease with the increase of its output. In the next few years, it is expected to be close to the current cost price of graphite anode materials.

　　Huzhou Weihong is currently one of the most successful companies promoting lithium titanate battery technology and other fast-charging batteries in the domestic industry.

　　The lithium titanate material produced by Huzhou Weihong is mainly used in its own lithium titanate battery products. The continuous expansion of Huzhou Weihong's lithium titanate battery products in domestic and foreign markets has also played a good role in demonstrating the application of lithium titanate technology in the electric vehicle and energy storage market.

　　Shenzhen Betterray is currently the world's largest supplier of carbon anodes for lithium batteries. The company has a strong R&D team and is also one of the drafters of the lithium titanate industry standard. Shenzhen Beterui's strong sales network will also take the lead in the sales of lithium titanate, and has launched two products, carbon-coated lithium titanate and carbon-free coated lithium titanate. However, the current lithium titanate material is not Beterui's main product. As the lithium titanate battery market has not yet been fully developed, the company has not yet formulated a long-term plan for the production of lithium titanate materials.

　　2. Lithium titanate battery and its application in electric vehicles and energy storage

　　There are not many manufacturers that can mass produce lithium titanate batteries in the world, mainly represented by the United States Austrian Titanium and Japan's Toshiba Group. The application markets of lithium titanate batteries mainly include electric vehicles, energy storage markets and industrial applications.

　　The American Austrian Titanium has its own unique core technology in the manufacture of lithium titanate batteries. It is still in a leading position in the manufacture of large-scale lithium titanate batteries in the world, and has solved the so-called "flatulence" problem. At present, its fourth-generation 65Ah monolithic lithium titanate battery has been used in energy storage systems, and there is still no significant capacity degradation after tens of thousands of cycles at 65°C.

　　In terms of the application of lithium titanate battery system, the hybrid electric bus provided by Aotea for California, USA, has been put into operation in 2008. Its fuel economy index is 106.4kg/L, which is much higher than the 23.8kg/L of ordinary diesel generators. The company provided a 1MW storage system for the Hawaii Institute of Natural Energy's 10.5MW wind farm and connected it to the local power grid, as well as a three-year technical support service. This lithium titanate battery energy storage system is mainly used to regulate the voltage fluctuation of renewable energy and control the load change rate of the unit within 1MW/min.

　　Austrian Titanium's 1MW large-capacity high-power energy storage unit is currently the only large-capacity lithium titanate battery product in the US power grid that has passed more than two years of on-site commercial operation and performance and quality inspection. The number of cycles of the energy storage system exceeds 500,000, the total charge and discharge power exceeds 3300MWh, the system capacity loss is less than 2%, and the power has no obvious attenuation.

　　Toshiba Japan mass-produced lithium titanate batteries under the brand "SCiB". Among them, 3.2Ah, 10Ah and 20Ah aluminum shell prismatic batteries are mainly used for electric motorcycles, electric vehicles and car start-stop batteries. SCiB battery has the advantages of fast charging and long life. It can be charged more than 90% in 10 minutes, and its capacity is less than 10% at 3000 times of repeated charging and discharging. It has been applied to "EV-neo" electric motorcycles in batches.

　　In terms of energy storage, Toshiba is applying lithium titanate batteries to large-scale energy storage power stations and household energy storage systems through the Dongfeng of Japan’s New Sunshine Project. Another Japanese company, Murata, has developed a new type of lithium titanate battery that uses 5V lithium nickel manganate as the positive electrode. The voltage difference is 3.2V, and the energy density can reach 130Wh/K song, which exceeds the current level of lithium iron phosphate batteries.

　　There are many domestic companies in the production of lithium titanate batteries, such as Huzhou Weihong, Zhuhai Yinlong, Shenzhen Bo Leida, Tianjin Gateway Power Industry Co., Ltd., Xingneng, CITIC Guoan Mengguli Power Technology Co., Ltd., Hunan Shanshan and many small-scale lithium titanate battery manufacturers around Shenzhen.

　　Huzhou Weihong has been committed to the development of lithium titanate technology since its establishment in 2006. The company has vertically integrated the lithium titanate materials, separators, electrolytes and cathode materials required for the production of its lithium titanate batteries. In recent years, in order to meet market demand, Huzhou Weihong has a daily production capacity of 80,000 10Ah lithium titanate battery products and twice the production capacity of multiple positive electrode lithium battery products for lithium titanate batteries.

　　As of the end of 2014, Huzhou Weihong’s 10-minute fast charging battery system has been equipped with more than 3,000 hybrid-powered electric buses, which are mainly sold to the UK, the Netherlands and Chongqing, China. In the energy storage market, Huzhou Weihong has installed lithium titanate battery energy storage systems for grid frequency regulation and grid demand management in Vermont, the United States and Chongqing, China.

　　Zhuhai Yinlong’s current mass-produced lithium titanate battery products include 20Ah and 65Ah soft-pack batteries and 25Ah, 30Ah and 55Ah cylindrical batteries. The performance indicators have reached the lithium titanate batteries produced by the United States Austrian Titanium. The battery has more than 16,000 cycles of 100% DOD, and 1.6 million cycles of 10% DOD. These batteries have passed the third-party inspection by the Northern Automobile Quality Supervision, Inspection and Appraisal Institute (201 Institute).

　　In terms of application, Yinlong's new pure electric buses use cylindrical, long-life, and fast-charge-discharge lithium titanate batteries. The cruising range can reach 30-80km, and the fast charging only takes 6-10 minutes. It can also be used for night valley electricity. Slow charge for 30 to 60 minutes to fully charge. This series of models has been successfully put on public transport systems in Zhanjiang, Guangdong, Handan, Hebei, and Shijiazhuang.

　　The antique pan-dang vehicle specially designed and developed by Yinlong for Beijing Public Transport was put into commercial operation in September 2014. The car was also designated as the official designated car for the Beijing APEC meeting. In the energy storage market, Yinlong cooperated with the State Grid and China Southern Power Grid to undertake the 863 national energy storage project, and provided two 2MWh and one for the Zhangbei Wind and Solar Storage and Transmission Demonstration Station and the Shenzhen Baoqing Battery Energy Storage Station. Part of the modules, battery box design and system solutions of the 600kWh lithium titanate system.

　　Shenzhen Bo Leida can prepare Li4Ti5O12 materials with good performance through unique material processing methods, and through technical research projects, starting from the improvement of the production process of lithium titanate batteries, the design and preparation of high-performance Li4Ti5O12 have made significant progress. The mass-produced products include 17Ah, 20Ah and 25Ah cylindrical batteries, which solved the problem of easy flatulence of lithium titanate batteries, obtained high-performance lithium titanate battery products, and obtained authoritative third-party inspection reports.

　　Boleida Company started with the design of high-power Li4Ti5O12 electrode materials, and studied the side reactions of Li4Ti5O12 materials to reveal the gas generation mechanism and solution mechanism. It has made a major breakthrough in the large-scale application of Li4Ti5O12 electrode materials in power batteries.

　　Tianjin Gateway has obtained the transfer of the lithium titanate battery production technology from American Austrian Titanium, and combines its own technology accumulation in the production of polymer soft pack power batteries for many years and has its own characteristics. The company successfully broke through the problem of flatulence, and has the technology and ability to mass produce large-size single lithium titanate batteries, with a battery capacity of 60Ah and a cumulative shipment of 20 million Ah.

　　The battery can withstand continuous charging and discharging above 10C, with a life span of more than 20,000 times, and a temperature range of -40～60℃. It is mainly used in fast charging buses and frequency modulation energy storage power stations.

　　Difficulties and development direction of lithium titanate battery technology development

　　1. Reasons for developing lithium titanate battery technology in China

　　The competition of lithium titanate battery technology in various energy storage batteries in our country should have the advantages of time, location and people. In terms of service life alone, the long cycle life of lithium titanate batteries is far better than that of various lead-acid batteries; its efficiency, cost and electrochemical performance are even better than those of sodium-sulfur and flow vanadium battery systems.

　　The main market for lithium battery products has been portable electrical appliances such as mobile phones and laptop computers over the years. Although the use of mobile phones and laptops in China is large, most of them are not domestic brands. Therefore, the sales capacity of domestic lithium battery manufacturers in portable appliances is lower than that of Japanese and Korean products.

　　However, the applicable market for lithium titanate technology is hybrid electric vehicles, special industrial applications and energy storage applications such as frequency modulation and grid voltage support. These markets are still in their infancy in the world, and it is not yet known who is the leader. Lithium titanate technology is expected to become a leader in these markets.

　　China's population base accounts for about 1/5 of the world. Due to its large population, China's electric vehicle, energy storage and industrial application market is a huge market coveted by multinational companies in many countries. In recent years, the Chinese government has attached great importance to the development of electric vehicles and energy storage industries, and various national incentive policies have been introduced. Chinese-made lithium titanate battery systems have been used in hybrid electric buses in Chongqing and Europe, wind and solar storage demonstration stations in Zhangbei, and Baoqing energy storage power stations in Shenzhen, which have accumulated data for commercial applications for several years.

　　In addition, the upstream and downstream of China's lithium battery industry chain have long been a climate. In addition to the complete battery material supply and equipment manufacturing capacity, the production capacity of lithium battery products is also one-third of the world's Japan and South Korea. This allows China's lithium battery manufacturers to transform from traditional lithium battery production to lithium titanate battery product production with innate conditions.

　　China has already had strong and experienced enterprises such as Xingneng, Zhuhai Yinlong, and Huzhou Weihong in the production of lithium titanate materials. Representative companies that stand out in the production of lithium titanate batteries include Huzhou Weihong, Zhuhai Yinlong, Shenzhen Bo Leida, and Tianjin Gateway.

　　These companies have initially established their own sales channels in the domestic and international electric vehicle and energy storage markets. It is especially worth pointing out that Shenzhen Bo Leida has a series of proprietary technologies and intellectual property rights from material production to battery production and system integration. At present, China's lithium battery industry is still a rare manufacturer with independent intellectual property rights.

　　2. Bottlenecks in the production of lithium titanate materials, batteries and battery packs

　　Since lithium titanate battery technology has many advantages that other lithium batteries can’t match, why has it been so far used in China’s energy industry and even the world’s energy sector?