Cai Chen, Gao Lin, Sun Tao, Koenig Gary M
Department of Chemical Engineering, University of Virginia, 102 Engineers Way, Charlottesville, Virginia 22904-4741, United States.
Department of Materials Science and Engineering, University of Virginia, 395 McCormick Road, Charlottesville, Virginia 22904, United States.
ACS Appl Mater Interfaces. 2023 Jul 26;15(29):34662-34674. doi: 10.1021/acsami.3c02896. Epub 2023 Jul 11.
Due to their high energy density, lithium-ion batteries have been the state-of-the-art energy storage technology for many applications. Energy density can be further improved by engineering of the electrode architecture and microstructure, in addition to more common improvements via materials chemistry. All active material (AAM) electrodes consist of only the electroactive material that stores energy, and such electrodes have advantages to conventional composite processing with regards to improved mechanical stability at increased thicknesses and ion transport properties. However, the absence of binders and composite processing makes the electrode more vulnerable to electroactive materials with volume change upon cycling. Also, the electroactive material must have sufficient electronic conductivity to avoid large matrix electronic overpotentials during electrochemical cycling. TiNbO (TNO) and MoO (MO) are electroactive materials with potential advantages as AAM electrodes due to relatively high volumetric energy density. TNO has higher energy density, and MO has much higher electronic conductivity, and thus a multicomponent blend of these materials was evaluated as an AAM anode. Herein, blends of TNO and MO as AAM anodes were investigated, where this is the first use of a multicomponent AAM anode. Electrodes that had both TNO and MO had the highest volumetric energy density, rate capability, and cycle life relative to single component TNO and MO anodes. Thus, using multicomponent materials provides a route to improve AAM electrochemical systems.
由于其高能量密度，锂离子电池一直是许多应用中的先进储能技术。除了通过材料化学进行更常见的改进外，还可以通过设计电极结构和微观结构来进一步提高能量密度。所有活性材料（AAM）电极仅由存储能量的电活性材料组成，并且这种电极在增加厚度时的机械稳定性和离子传输性能方面相对于传统复合工艺具有优势。然而，没有粘合剂和复合工艺使得电极更容易受到循环时体积变化的电活性材料的影响。此外，电活性材料必须具有足够的电子导电性，以避免在电化学循环过程中出现大的基体电子过电位。TiNbO（TNO）和MoO（MO）是具有潜在优势的电活性材料，可作为AAM电极，因为它们具有相对较高的体积能量密度。TNO具有更高的能量密度，而MO具有更高的电子导电性，因此对这些材料的多组分混合物作为AAM阳极进行了评估。在此，研究了TNO和MO作为AAM阳极的混合物，这是首次使用多组分AAM阳极。相对于单组分TNO和MO阳极，同时含有TNO和MO的电极具有最高的体积能量密度、倍率性能和循环寿命。因此，使用多组分材料提供了一种改进AAM电化学系统的途径。
