Chinese patent analysis of power-type lithium-ion battery electrodes

Using the PIAS patent search tool, the CNIPR central data station is used to search for Chinese patent data, and TDA is used for patent data analysis. In order to grasp the overall situation of Chinese patent applications for power-type lithium-ion battery electrodes, this paper focuses on the overall status of Chinese patents, domestic and foreign applicants of Chinese patents and patent applications in various provinces. Through the analysis of this article, we can understand the technology development status and patent layout of the industry, which will help enterprises to grasp their competitive position in the industry and the technical situation of competitors, and provide reference for formulating effective market strategies and patent strategies.

1. Application status

China’s power lithium-ion battery electrode technology development can be roughly divided into the following two stages.

(1) Slow development stage

In the period before 2004, the number of patent applications for electrode technology for power lithium-ion batteries in China did not exceed 100 per year. During this period, the market demand for power lithium-ion batteries, especially the power batteries for electric vehicles, is still in its infancy. From the perspective of patent applications, both technology research and development and market demand are developing slowly.

(2) Rapid development stage

Since 2004, China’s power-type lithium-ion battery electrode technology patent applications have developed rapidly. At the peak of filings in 2013, the annual filing volume was close to 600, six times the number of patent filings in 2004. From the perspective of market development, during this period, China has introduced preferential policies to promote the development of new energy vehicles, and factors such as air pollution control and energy crisis have promoted the rapid development of the electric vehicle industry. Reflected in the number of patent applications, the strong market demand has driven the enthusiasm of applicants to apply for patents, and a combination of various factors has led to a rapid increase in the number of patent applications in China.

2. Composition of applicants

Applicants from countries other than China are mainly from Japan and South Korea, of which Japan has the largest number of applications, accounting for 73% of the total number of foreign applications in China.

Figure 1 shows the trend of patent filings by major foreign applicants in China. Before 2000, the number of patent applications in Japan in the field of power-type lithium-ion battery electrodes was not large, with an average of no more than 10 per year. After 2000, the number of Japanese patent applications in China has increased significantly, and the speed and magnitude of the increase are far more than other foreign applicants. It can be seen that Japan attaches great importance to the patent layout in China, and the United States and South Korea attach great importance to the Chinese market, but they do not have too much technology output, and do not invest much in China’s patent layout.

Among the top 30 patent applicants in the field of power-type lithium-ion battery electrode technology, Japanese companies have an advantage in the number of patent applications, followed by Korean companies. Domestic applicants in China are mainly composed of companies and universities. Companies include BYD, Tianjin Lishen, CITIC Guoan Guli, etc.; universities include Zhejiang University, Tsinghua University, Central South University and Fudan University. Among the top 30 foreign applicants, there are no universities and research institutions.

In the period before 1996, the total number of patent applications was small, mainly those filed by Chinese domestic applicants; during the period from 1996 to 2002, the number of patents applied by foreign applicants was more than that of Chinese domestic applicants, and the proportion was more than 80% at the most; since 2002, the number of patents filed by Chinese domestic applicants has increased year by year. In 2010, the proportion reached 80%, and in 2013, it exceeded 90%. From the composition of Chinese patent applicants, it can be seen that Chinese researchers have increased their understanding of intellectual property rights, showing a positive trend in patent layout and market competition.

3. Technology trends and personnel trends

(1) Technology trends

Figure 2 shows the technical trend of Chinese patents in the field of power lithium-ion battery electrodes. White represents technologies that were new in that year, and black represents technologies that existed before that year. With the rapid development of electrode technology in the mid-1990s, industrial technology research has flourished, and new technologies have begun to emerge. After 2005, many new technologies appeared. Compared with the rapid development momentum of industrial technologies, the growth rate of new technologies was comparable to that of industrial technologies, and new technologies continued to appear.

(2) Personnel trends

The new trend of Chinese patent inventors is shown in Figure 3. The obvious difference from the steady growth of new technologies is that in the mid-1990s, new researchers in electrode technology began to increase significantly, and around 2006, there was a rapid growth trend, indicating that relevant research institutions attach great importance to electrode technology and invest a large number of researchers in R&D work; and, the number of existing researchers continues to increase, indicating that the number of fixed researchers is increasing, and the research has a certain continuity.

4. Patent application by province

In the field of power lithium-ion battery electrode technology, Guangdong ranks first in the ranking of applications in various provinces in China, followed by Beijing and Jiangsu. The top eight provinces and cities accounted for 75% of the total applications. It shows that patent applications are relatively concentrated, and technological research and development forces are mainly concentrated in economically developed provinces and cities such as Guangdong and Beijing. In general, except for Guangdong, which has a large number of patent applications, among the top 8 Chinese provinces and cities, the gap in the number of patent applications in the field of power-type lithium-ion battery electrode technology is not large.

Figure 4 shows the trend distribution of the top 7 provincial and municipal patent applications in terms of annual patent technology applications. Jiangsu started a little late and started to develop in 2006. Beginning in 2009, patent applications in Guangdong, Beijing and Jiangsu began to accelerate. In general, the development of electrode technology in China has grown rapidly in recent years, but the total amount is still small, and it is still in a period of low-speed development.

Read more: Global patent analysis of power lithium-ion battery electrodes