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铜配位的纤维素离子导体可用于固态电池
作者:小柯机器人 发布时间:2021/10/23 19:59:12

一个由马里兰大学Hu Liangbing带领的合作小组近日发现,铜配位的纤维素离子导体可用于固态电池上。相关论文于2021年10月20日发表于国际顶尖学术期刊《自然》杂志上。

在该研究中,通过对分子通道进行工程化改造,研究人员报道了一种实现高性能固体聚合物离子导体的通用策略。通过将铜离子(Cu2+)与一维纤维素纳米纤维的配位,该研究团队证明了将通常情况下离子绝缘的纤维素内的分子通道打开,可使Li+离子沿着聚合物链快速运输。除了高Li+电导率(在室温下沿分子链方向1.5 × 10-3 S/cm),Cu2+配位的纤维素离子导体也表现出高迁移数(0.78,相比于其他聚合物中的0.2-0.5)和宽的电化学稳定窗口(0-4.5伏),以能够适应Li-金属阳极和高压阴极。这种一维离子导体还允许离子渗透到厚的LiFePO4固态阴极中,以用于高能量密度的电池。此外,研究人员还验证了这种分子通道工程方法在其他聚合物和阳离子上的通用性,实现了类似的高电导率,其意义可能不仅仅在于安全、高性能固态电池应用中。

据了解,虽然固态锂(Li)金属电池具有高能量密度和安全性,但现有的固体离子导体无法满足电池运行的严格要求。无机离子导体允许快速离子传输,但其刚性和脆性的性质阻碍了与电极良好的界面接触。相反,对锂金属稳定的聚合物离子导体本身提供了更好的界面相容性和机械耐受性,但由于离子传输需与聚合物链的运动耦合,导致离子导电性通常较差。

附:英文原文

Title: Copper-coordinated cellulose ion conductors for solid-state batteries

Author: Yang, Chunpeng, Wu, Qisheng, Xie, Weiqi, Zhang, Xin, Brozena, Alexandra, Zheng, Jin, Garaga, Mounesha N., Ko, Byung Hee, Mao, Yimin, He, Shuaiming, Gao, Yue, Wang, Pengbo, Tyagi, Madhusudan, Jiao, Feng, Briber, Robert, Albertus, Paul, Wang, Chunsheng, Greenbaum, Steven, Hu, Yan-Yan, Isogai, Akira, Winter, Martin, Xu, Kang, Qi, Yue, Hu, Liangbing

Issue&Volume: 2021-10-20

Abstract: Although solid-state lithium (Li)-metal batteries promise both high energy density and safety, existing solid ion conductors fail to satisfy the rigorous requirements of battery operations. Inorganic ion conductors allow fast ion transport, but their rigid and brittle nature prevents good interfacial contact with electrodes. Conversely, polymer ion conductors that are Li-metal-stable usually provide better interfacial compatibility and mechanical tolerance, but typically suffer from inferior ionic conductivity owing to the coupling of the ion transport with the motion of the polymer chains1,2,3. Here we report a general strategy for achieving high-performance solid polymer ion conductors by engineering of molecular channels. Through the coordination of copper ions (Cu2+) with one-dimensional cellulose nanofibrils, we show that the opening of molecular channels within the normally ion-insulating cellulose enables rapid transport of Li+ ions along the polymer chains. In addition to high Li+ conductivity (1.5 × 103 siemens per centimetre at room temperature along the molecular chain direction), the Cu2+-coordinated cellulose ion conductor also exhibits a high transference number (0.78, compared with 0.2–0.5 in other polymers2) and a wide window of electrochemical stability (0–4.5 volts) that can accommodate both the Li-metal anode and high-voltage cathodes. This one-dimensional ion conductor also allows ion percolation in thick LiFePO4 solid-state cathodes for application in batteries with a high energy density. Furthermore, we have verified the universality of this molecular-channel engineering approach with other polymers and cations, achieving similarly high conductivities, with implications that could go beyond safe, high-performance solid-state batteries.

DOI: 10.1038/s41586-021-03885-6

Source: https://www.nature.com/articles/s41586-021-03885-6

期刊信息

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:42.778
官方网址:http://www.nature.com/