Kang Jieun, Lee Seungho, Hwang Jinwoo, Kim Sungho, Lee Sangyeop, Yoo Seokkeun, Han Jeong Woo, Ryu Ja-Hyoung, Ryu Jaegeon, Park Soojin
Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.
Adv Mater. 2023 Nov;35(47):e2306157. doi: 10.1002/adma.202306157. Epub 2023 Oct 22.
Advanced energy-storage devices are indispensable for expanding electric mobility applications. While anion intercalation-type redox chemistry in graphite cathodes has opened the path to high-energy-density batteries, surpassing the limited energy density of conventional lithium-ion batteries , a significant challenge remains: the large volume expansion of graphite upon anion intercalation. In this study, a novel polymeric binder and cohesive graphite cathode design for dual-ion batteries (DIBs) is presented, which exhibits remarkable stability even under high voltage conditions (>5 V). The innovative binder incorporates an acrylate moiety ensuring superior oxidative stability and self-healing features, along with an azide moiety, which allows for azacyclic covalent bonding with graphite and interchain crosslinking. A simple 1-h ultraviolet treatment is sufficient for binder fixation within the electrode, leading to the covalent bond formation with graphite and the creation of a robust three-dimensional network. This modification facilitates deeper and more reversible anion intercalation, leading to improved capacity, extended lifespan, and sustainable anion storage. The binder design, exhibiting exceptional adhesive properties and effective stress mitigation, enables the construction of ultrathick graphite cathodes. These findings provide valuable insights for the development of advanced binders, paving the way for high-performance DIBs.
先进的储能设备对于扩大电动移动应用至关重要。虽然石墨阴极中的阴离子插层型氧化还原化学为高能量密度电池开辟了道路，超越了传统锂离子电池有限的能量密度，但仍存在一个重大挑战：阴离子插层时石墨的大量体积膨胀。在本研究中，提出了一种用于双离子电池（DIBs）的新型聚合物粘合剂和粘性石墨阴极设计，即使在高压条件（>5 V）下也表现出卓越的稳定性。这种创新的粘合剂包含一个丙烯酸酯部分，确保优异的氧化稳定性和自修复特性，以及一个叠氮化物部分，它允许与石墨形成氮杂环共价键并进行链间交联。简单的1小时紫外线处理足以使粘合剂固定在电极内，导致与石墨形成共价键并创建一个坚固的三维网络。这种改性有助于更深层次和更可逆的阴离子插层，从而提高容量、延长寿命并实现可持续的阴离子存储。这种粘合剂设计具有出色的粘合性能和有效的应力缓解能力，能够构建超厚的石墨阴极。这些发现为先进粘合剂的开发提供了有价值的见解，为高性能双离子电池铺平了道路。
