## 3 Results
### RGR and RDGR Combination Indicator  
Figure 1 shows the RGR and RDGR results, where the dark color bar presents RGR and the light color bar shows RDGR. As mentioned above, the RGR value can be interpreted as the \"innovation strength\" of the specific technology and the RDGR value as the \"innovation potentiality\". By combining RGR and RDGR, this indicator is a strong visualization approach to identify the R&D strategies in specific technology among several companies during 2005-2015. The modified RGR and RDGR indicator based on issued patents and can show the actual competitiveness of patent assignees in the field of electrolyte, whereas the patent application count-based method, previous Ernst' indicator, shows the research efforts invested. Figure 1a shows the calculated RGR and RDGR values of six companies in the CPC code H01M10/0567, namely \"additives\". Ube, Panasonic, and Samsung SDI showed greater than 1 for the RGR value, indicating that they had better innovation strength in developing additives than other companies. However, the negative RDGR values of Samsung SDI and Panasonic represented less innovation potentiality in the latter 5 years. In particular, Mitsubishi Chem. had an RGR value close to 0, which indicates less active development in additives or the relevant patenting activity was less notable when compared to other R&D activities within the enterprise. However, Mitsubishi Chem. showed a much higher RDGR value, 6.72, which means the average growth rate of issued patents were about six times in the second 5 years. It also represents that the company's innovation in additives was more effective. Sony and LG Chem. had lower innovation strength in additives technology, which results in less innovation potentiality. Figure 1b illustrates that the patenting activities of Panasonic, Sony, LG Chem., and Samsung SDI show great innovation strength with a greater RGR value. It means that they obtained considerable numbers of patents related to lithium salts technology. However, they were less active, and less progress was shown in the latter 5 years with RDGR less than 1. Especially, Samsung SDI shows a negative RDGR value, which means the company was granted less patents in the second 5 years from the major patent offices. Ube shows delayed innovation strength and potentiality with negative RGR and RDGR values. It indicates that Ube was not specialized and interested in the development of lithium salts. Mitsubishi Chem. 's innovation strength was lower than Panasonic, Sony, LG Chem., and Samsung SDI and had average innovation potentiality in lithium salts. \begin{table}
\begin{tabular}{c c} \hline
**Company/(Country)** & **Patent Counts** \\ \hline Samsung SDI/(Korea) & 653 \\ LG Chem./(Korea) & 505 \\ Panasonic/(Japan) & 446 \\ Sony/(Japan) & 321 \\ Ube/(Japan) & 241 \\ Mitsubishi Chem./(Japan) & 240 \\ \hline \end{tabular}
\end{table} 
Table 1: Patent counts of top six patent assignees. In Figure 1c, Ube, Panasonic, Sony, and LG Chem. show better innovation strength in solvent technology. Especially, Panasonic outperformed others with an RGR value greater than 4, which means that Panasonic was great in the development for solvents. Nevertheless, they obtained fewer patents in the second 5 years and show less potentiality for innovation with a RDGR value less than 1. In particular, Mitsubishi Chem. had shown increasing interests and progress in solvent technology, as the company was the only one among six major assignees with a positive and high RDGR value. Comparatively, Samsung SDI had lower innovation strength and shows the weak potentiality in solvents technology. With another viewpoint for Figure 1a-c, six patent assignees had totally different patenting strategies in the technological fields of electrolyte compositions. For example, in the Japanese companies, Ube is specialized in additives, Panasonic shows leadership in solvents and lithium salts, and Sony shows a strong presence in lithium salts. In addition, in the Korean firms, LG Chem.