翻译成中文：
Measuring Innovation by Using Patents in Fuel cells

A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes. Every fuel cell also has an electrolyte, which carries electrically charged particles from one electrode to the other, and a catalyst, which speeds the reactions at the electrodes. Hydrogen is the basic fuel, but fuel cells also require oxygen. One great appeal of fuel cells is that they generate electricity with very little pollution–much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
From the perspective of energy conservation and environmental protection, fuel cell is the most promising power generation technology. 
	Patents is one of innovation metrics in an area of energy technology. Patents provide an easy way to measure innovation. After all, patent statistics are easy to come by, they are objective and quantifiable, so we can quickly count the number of patents by company, city or country, and immediately understand how innovation varies by geography, industry or even time period. Therefore, patents provide a relatively objective measure of new knowledge. Patents are required to describe something novel and not obvious; to be patented "an invention must be something not already known from prior publication, or not a part of the experience of those skilled in the art" (Walker, 1995). Patents thus provide a good measure of technologically new knowledge as defined above. Several studies have recently used patents as a measure of innovation performance (Henderson and Cockburn, 1994). 
	As for fuel cells, I used patentsscope website to research the top 3 countries in patents area. Three strongest countries in fuel cells are the United States, Japan and Germany. The US is the world's fastest-growing and largest market for fuel cell and hydrogen technology. The US research on fuel cell technology is broad, especially in automobiles, but also in other applications such as fixed power stations. For example, a company called UTC Fuel Cells, it mainly develops and manufactures fuel cell systems for buses, automobiles, aerospace and ships. Since the early 1990s, more than 300 united technology dynamics stationary fuel cell power stations have been installed in educational facilities, hospitals, factories, office buildings, and supermarkets in the United States, and 120 PureMotion fuel cell systems have been used on buses in Connecticut, California, and Europe. The U.S. focus on fuel cell development is to improve fuel efficiency and reduce the cost of fuel cell production and generation.
	The second strongest company is Japan. The main drivers of hydrogen fuel technology in Japan are the automotive industry, primarily the Japanese auto industry. And in the Japanese agency, Toyota as the main representative. Toyota has filled the largest number of patent applications in Japan, where it is based. In recent years, Toyota has invested a lot of research and development funds in new-energy vehicles, especially fuel-cell vehicles. The prospects for a clean and sustainable energy future in Japan continue to increase as both the government and many private sector companies further their commitments to hydrogen and fuel cells.  Japan’s vision is that fuel cells, as a power source for several modes of transportation, as well as stationary and mobile applications, will allow the country to diversify and strengthen its energy infrastructure.  
	The third strongest country is Germany. Germany has implemented a number of hydrogen energy industry chain involving hydrogen production, transportation, storage and fuel cell applications, and has applied fuel cell technology to a variety of fields such as automobiles, ships and power stations. In 2006, the German government began a strategic partnership with national industry and science leaders to advance the role of hydrogen and fuel cell technology in Germany’s energy system. The original objectives of the National Innovation Programme for Hydrogen and Fuel Cell Technology (NIP) were to secure Germany’s position as a leader in fuel cell and hydrogen technology, accelerate market development in a wide range of applications, and strengthening the country’s hydrogen and fuel cell value chain.
Patents include detailed information on the nature of the invention with long time series, huge amounts of data. Meanwhile, the number of patents reflects the level of technological innovation in a country and an enterprise. However, most important innovations are not patented, and many patents do not represent important innovations. In patent analysis, those innovations that are not patented are not considered innovations, even though many of them bring great benefits to users. Besides, as early as the 1960s, Jakob Schmookler, an innovation scholar, pointed out that patent is a good indicator of innovation "activity", but can’t reflect the actual economic output caused by innovation activity.