First Principles Design of Ionomers for Facile Ion Transport

方便离子传输的离聚物的第一原理设计

• 批准号: 0933391
• 负责人: Ralph Colby
• 金额: $ 30.35万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0933391&HistoricalAwards=false
• 关键词: First; Principles; Design; Ionomers; Facile

0933391ColbyCurrent lithium batteries use a nanoporous polypropylene membrane filled with lithium salts dissolved in high dielectric constant solvents as the separator between electrodes. This technology has problems with safety and regardless of the choice of anion, which moves 5-10X faster than Li+, resulting in anion build-up at electrodes that significantly reduces battery efficiency, maximum battery power and recharge time. The obvious choice for a replacement membrane is a single-ion conducting polymer (ionomer) that has all anions covalently bonded to the polymer, has no solvent to leak out of the battery and can easily be made into a thin film. Unfortunately, the best ionomer membranes have Li+ ion conductivities 100X too small for practical applications. The PI leads a five-PI DOE-funded team that is attempting to design superior ionomers for lithium battery membranes, but also is facing a very broad design space, with 30 polar groups that could be added as side chains and 20 anions that could be attached to polymers. Combined with at least five backbones that have low Tg, there are thousands of possible combinations. Furthermore, he is a co-PI on a seven-PI Army MURI aiming to synthesize ionomer membranes for actuators, which additionally have flexibility in the choice of cation. The intellectual merits of this research are two-fold: (1) The proposed research will suggest anion, polar side group, backbone combinations worthy of synthesis and directly aid the seven synthesis students on the two teams mentioned above. (2) Ab initio calculations can be rapidly applied to a wide variety of anions and cations in different polar media, enabling a detailed understanding of ion interactions and solvation by polar groups, which should propel our modeling efforts with Sanat Kumar at Columbia. The broader impacts of our proposed research are three-fold. (1) The understanding of how to design ionomers for improved ion-conduction will not only impact advanced lithium batteries and actuators, but is also vital for other battery membranes (such as commercial ones transporting F-) and the membrane electrode assemblies for fuel cells. All ion-conducting membranes suffer from the fact that only a tiny fraction of counter-ions participate in conduction, and the proposed research directly addresses boosting the conducting ion content. (2) Materials development in the energy field is expected to play a very important role in the future of the United States economy and way of life. (3) Graduate students trained in this "energy materials" arena will be in enormous demand in both US industry and academia for at least the next ten years. Penn State has superb undergraduates and research motivates them to attend graduate school (15 of 25 undergraduate researchers in the PI's group over the past 14 years have gone on to graduate school in science and engineering) with many current undergraduates interested in "energy materials", including current REU-funded student Daniel King, a Materials Science and Engineering junior who has won our department's Undergraduate Research Fellowship for three consecutive years.

0933391电流锂电池使用一种纳米多孔聚丙烯膜，该膜充满锂盐，溶解在高介电恒定溶剂中，作为电极之间的分离器。该技术在安全性方面存在问题，无论选择如何选择阴离子，它的移动速度比Li+快5-10倍，从而导致电极在电极上堆积，从而大大降低了电池效率，最大电池电量和充电时间。替换膜的明显选择是单离子导电聚合物（Ionomer），其所有阴离子都共价粘结到聚合物与聚合物，没有溶剂从电池中泄漏，并且可以轻松地将其制成薄膜。不幸的是，最好的离子膜具有Li+离子电导率100倍，用于实际应用。 PI领导了一支由五pi的DOE资助的团队，该团队正在尝试为锂电池膜设计出色的离子体，但也面临着一个非常广阔的设计空间，可以将30个极性组添加为侧链和20个阴离子，可以是20个阴离子附着于聚合物。结合至少五个TG低的骨干，有数千种可能的组合。此外，他是一名七杆军队Muri的副驾驶，目的是将电离膜构成执行器的离子膜，此外，它在选择阳离子方面具有灵活性。 这项研究的智力优点是两个方面：（1）拟议的研究将暗示阴离子，极地小组，值得综合的骨干组合，并直接在上述两个团队中帮助七个合成学生。 （2）从头开始计算可以迅速应用于不同极地培养基中的各种阴离子和阳离子，从而使极地群体对离子相互作用和溶剂化有了详细的了解，这应该推动我们与哥伦比亚Sanat Kumar的建模工作。我们拟议的研究的更广泛影响是三倍。 （1）理解如何设计电离器以改进离子传导不仅会影响高级锂电池和执行器，而且对于其他电池膜（例如运输F-的商业膜）和燃料电池的膜电极组件至关重要。所有离子传导膜都遭受这样的事实，即只有一小部分反国参与传导，而拟议的研究直接解决了促进导电含量的促进。 （2）预计能源领域的材料发展将在美国的经济和生活方式的未来中发挥非常重要的作用。 （3）至少在接下来的十年中，接受了“能源材料”竞技场培训的研究生将在美国行业和学术界都有巨大的需求。宾夕法尼亚州立大学（Penn State）拥有一流的本科生，研究激励他们上研究生院（过去14年中，PI小组的25名本科研究人员中有15年中有许多目前对“能量材料”的本科生，包括现任REU资助的学生丹尼尔·金（Daniel King），这是一名材料科学和工程大三学生，连续三年赢得了我们部门的本科研究奖学金。