SBIR Phase I: Porous Carbon Substrate for Long Life Lithium-sulfur Batteries

这个小企业创新研究第一阶段项目将解决与高能锂离子电池开发相关的问题。如今，移动设备需要更快的性能和更小的尺寸以获得更好的便携性。然而，这些设备中更快的处理器施加了能量密度要求，将当今的锂电池技术推向了极限。用于移动设备的最先进锂离子电极材料的最大能量密度为0.28-0.6 kWh/kg。我们的团队正在开发一种商用二次/可充电Li-S电池，理论能量密度为2.3 kWh/kg，这将极大地改变所有便携式设备的电能存储格局。这种锂电池的发展一直受到循环寿命差的限制。该项目将通过开发一种最佳的多孔碳载体来隔离电池阴极中的硫，从而解决这一问题。宿主将限制多硫化物的溶解，以增加我们目前的硫注入碳纳米结构（S@C）复合阴极材料的循环寿命，从650次循环到1000次（或更多）循环。此外，通过使用低成本、商业上可用的碳原料（碳气凝胶、石墨烯和高硫煤），这项研究的结果可能会降低制造碳硫复合阴极的直接成本。这个项目的广泛影响/商业潜力是巨大的。锂离子电池目前的市场规模为110 - 130亿美元，预计到2020年将达到440亿美元。锂离子电池占便携式电子产品中使用的所有二次（可充电）电池的近75%。二次锂硫电池采用硫作为阴极，金属锂作为阳极，提供了基于两种固体元素的电池中最高的能量存储潜力。这些设备提供的能量容量是目前部署的锂离子电池技术的两倍多，重量只有锂离子电池的一半。如果这种潜力可以商业化，它有可能取代锂离子电池技术，因为它具有更高的能量密度、更低的成本和硫的广泛可用性。这可能会对移动设备、电动汽车市场和更广泛的能源存储市场产生重大影响，从而在所有这些领域实现更高的效率和性能。

This Small Business Innovation Research Phase I project will address issues related to the development of high-energy lithium-ion batteries. Today, mobile devices require faster performance and smaller sizes for greater portability. However, the faster processors in these devices impose energy density requirements that push today's lithium battery technologies to their limits. State-of-the-art lithium-ion electrode materials used in mobile devices produce a maximum energy density of 0.28-0.6 kWh/kg. Our team is developing a commercial secondary/rechargeable Li-S battery with a theoretical energy density of 2.3 kWh/kg, which could dramatically alter the electrical energy storage landscape for all portable devices. Development of this Li-S battery has been limited by poor cycle life. This project will remedy this by developing an optimal porous carbon host for sequestering sulfur in the battery cathode. The host will limit polysulfide dissolution in order to increase cycle life of our current sulfur-infused carbon nanostructure (S@C) composite cathode materials from 650 cycles to 1000 (or more) cycles. In addition, by utilizing low-cost, commercially available carbon feedstocks (carbon aerogels, graphene, and high-sulfur coal), the results of this research will likely reduce the direct costs of manufacturing carbon-sulfur composite cathodes.The broader impact/commercial potential of this project is significant. Li-ion batteries currently have a $11-13 billion market and the market size is expected to reach $44 billion by 2020. Li-ion batteries account for close to 75% of all secondary (rechargeable) batteries used in portable electronics. Secondary lithium-sulfur batteries employing sulfur as the cathode and metallic lithium as the anode offer the highest energy storage potential of any battery based on two solid elements. These devices offer more than twice the energy capacity of the currently deployed lithium-ion battery technology with half the weight. If this potential can be brought to commercialization, it has the potential to displace lithium-ion cell technology because of the higher energy density, low cost, and widespread availability of sulfur. This could have significant impacts on mobile devices, electric vehicles market, and the broader energy storage market, enabling greater efficiency and performance in all those sectors.