Open AccessHighly Aligned Ultra‐Thick Gel‐Based Cathodes Unlocking Ultra‐High Energy Density Batteries
Author(s) -
Yang Shichun,
Zhou Chaochao,
Wang Qiong,
Chen Binbin,
Zhao Yan,
Guo Bin,
Zhang Zhengjie,
Gao Xinlei,
Chowdhury Ridwanur,
Wang Huizhi,
Lai Chao,
Brandon Nigel P.,
Wu Billy,
Liu Xinhua
Publication year - 2022
Publication title -
energy and environmental materials
Language(s) - English
Resource type - Journals
ISSN - 2575-0356
DOI - 10.1002/eem2.12252
Subject(s) - materials science , electrode , cathode , lithium (medication) , porosity , chemical engineering , supercapacitor , nanotechnology , composite material , energy storage , tortuosity , current density , conductivity , current collector , electrochemistry , chemistry , medicine , power (physics) , physics , quantum mechanics , engineering , electrolyte , endocrinology
Increasing electrode thickness can substantially enhance the specific energy of lithium‐ion batteries; however, ionic transport, electronic conductivity, and ink rheology are current barriers to adoption. Here, a novel approach using a mixed xanthan gum and locust bean gum binder to construct ultra‐thick electrodes is proposed to address above issues. After combining aqueous binder with single‐walled carbon nanotubes (SWCNT), active material (LiNi 0.8 Co 0.1 Mn 0.1 O 2 ) and subsequent vacuum freeze‐drying, highly aligned, and low‐tortuosity structures with a porosity of ca. 50% can be achieved with an average pore size of 10 μm, whereby the gum binder‐SWCNT‐NMC811 forms vertical structures supported by tissue‐like binder/SWCNT networks allowing for excellent electronic conducting phase percolation. As a result, ultra‐thick electrodes with a mass loading of about 511 mg cm −2 and 99.5 wt% active materials have been demonstrated with a remarkable areal capacity of 79.3 mAh cm −2 , which is the highest value reported so far. This represents a >25× improvement compared with conventional electrodes with an areal capacity of about 3 mAh cm −2 . This route also can be expanded to other electrode materials, such as LiFePO 4 and Li 4 Ti 5 O 12 , and thus opens the possibility for low‐cost and sustainable ultra‐thick electrodes with increased specific energy for future lithium‐ion batteries.