Maxwell Technologies delivers first commercial application of Li-ion capacitor technology with CRRC-SRI in China
Maxwell Technologies, Inc., a leading developer and manufacturer of ultracapacitor-based energy storage and power delivery solutions, announced the first commercial application of lithium-ion capacitors, developed in conjunction with China Railway Rolling Stock Corporation (CRRC-SRI), China’s largest rail manufacturer. (Earlier post.)
The technology will be used for rapid energy regeneration in the trolley system in the capital city of Hunan province in China. Following last year’s announcement of Maxwell’s strategic partnership with CRRC-SRI to collaborate on developing next-generation capacitive energy storage solutions, this project is the first to leverage Maxwell’s new lithium-ion technology and validates its unique value proposition for rail applications.
Lithium-ion capacitors have emerged over the past few years as an approach to improve the energy density of ultracapacitors by combining a low potential Li-ion battery electrode (for example, insertion-type, pseudocapactive transition metal oxide and pre-lithiated carbon) and a high potential ultracapacitor electrode (typically commercial activated carbon).
The result is a wide cell potential window; however, operating at a wide cell potential window can be detrimental to cyclic stability—one of the hallmarks of ultracapacitors. Manufacturers thus pay close attention to electrolyte stability.
Maxwell’s lithium-ion capacitors deliver ultracapacitors’ high power density with lithium-ion batteries’ high energy density for onboard energy storage systems. Compared to traditional ultracapacitors, lithium-ion capacitors triple energy density and reduce the total weight of the energy storage system by 50%.
Lithium-ion capacitors can charge light rail vehicles in 30 seconds and keep them going for five to 10 minutes, ensuring the trolley will be able to restart quickly in constant stop-and-go traffic. The technology fulfills China’s rail requirements for energy savings and environmental protection.
CRRC-SRI will leverage lithium-ion capacitors for the Changsha Subway in Changsha, Hunan, as the single source of power for instant charging and discharging to propel the trolley.
As railways continue to be a dominant form of transportation in China, rail infrastructure increasingly needs dependable energy saving technologies. Maxwell Technologies’ lithium-ion capacitors fill that market demand today and ensure our trolleys are constantly moving. We’ve continued to place our trust in Maxwell and its energy storage expertise and look forward to working together to meet the needs of the growing China market.—Liu Baoming, chairman of CRRC-SRI
The commercial use of lithium-ion capacitors represents a transformation in the energy storage industry and a significant opportunity for Maxwell to revolutionize the way power is distributed in rail applications in China. Maxwell’s lithium-ion capacitors are the perfect solution for the growing rail market. As demand for energy storage solutions increases, we believe there is a large opportunity to use the technology in even more applications, such as grid firming, wind pitch control and robotics, to drive future revenue growth.—Dr. Franz Fink, president and CEO of Maxwell Technologies
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