China’s power lithium-ion battery patent development trend and distribution
As of June 30, 2014, a total of 5,131 Chinese patents for power lithium-ion batteries have been retrieved. In terms of analysis tools, TDA and Incopat of Thomson Reuters and the patent analysis software of State Intellectual Property Office Press are comprehensively applied.
1. Patent development trend
(1) Technology scale and growth rate
Figure 1 shows the trend of patent applications and patent growth rates in China for power lithium-ion batteries. The gray bars represent the number of Chinese patent filings, and the black curve represents the growth rate of Chinese patents. It can be seen that the trend of patent application in China is basically the same as that of the world, but it started late, and the development scale was only achieved after 2002, and it has shown a rapid development trend since then. The growth rate of patent applications in China has basically maintained a positive growth, and has stabilized in recent years, indicating that the technology is becoming mature.

(2) Technology and personnel trends
Figure 2 respectively show the area chart of the development trend of China’s power lithium-ion battery technology and personnel, in which the horizontal grid represents the original, and the dot grid represents the newly added. It can be seen that with the development of China’s power lithium-ion battery industry, new personnel and new technologies have begun to emerge rapidly. The difference is that the growth of new technologies is relatively flat, while the increase of new researchers has increased significantly.

(3) Technology life cycle
China’s power-type lithium-ion battery technology has entered the second stage of rapid technological growth around 2005 after the first stage of technology incubation (), and the number of patents and applicants has increased significantly. Beginning in 2012, the number of patents was close to that of 2011, but the number of applicants began to decrease. It is close to the development trend of the global power lithium-ion battery technology life cycle.
2. Patented technology distribution
Figure 3 shows the technology distribution and development trend of Chinese patent applications for power lithium-ion batteries. It can be seen from the pie chart that in China’s lithium-ion battery technology, electrode patents account for 54% of the total number of patents, followed by monomers accounting for 28%, and battery packs, separators and electrolytes account for less. It can be seen from the graph that the number of patents increases with the change of the years. Among them, the patent of electrode and separator started the earliest, and the patent of battery pack started the latest.

Most of the main applicants for China’s patented technology for power lithium-ion batteries are companies from other countries, and most of them are Japanese and Korean companies.
3. Regional distribution
(1) Strength distribution
The regions with the strongest relevant patents in China are concentrated in Guangdong, Jiangsu, Zhejiang and Beijing, accounting for 41.6% of the total, nearly half. The number of foreign patents in China accounted for 22.5% of the total, and the countries involved mainly included Japan, South Korea and the United States.
Figure 4 shows the application trends of the top 5 provinces in China by the number of patent applications for power lithium-ion batteries. After 2005, there has been rapid growth, which shows that the main patent application areas in China attach great importance to the research and development of power lithium-ion batteries, and foreign patents have also accelerated their layout in China.

(2) Distribution of technical fields in major regions
Figures 5 respectively show the distribution histogram and histogram of the proportion of the technical fields in the main areas of Chinese patents for power-type lithium-ion batteries. As can be seen from Figure 5(a), Guangdong occupies a leading position in various technical fields. Figure 5(b) shows that each region pays the most attention to electrode technology, with fewer patents in the fields of separators and electrolytes (electrolytes).

Further reading:
1. Global patent development trend of power lithium-ion battery
2. Regional distribution of global patents for power lithium-ion batteries