Nano-structured Li1.3Al0.3Ti1.7(PO4)3 coated LiCoO2 enabling compatible interface with ultrathin garnet-based solid electrolyte for stable Li metal battery. (August 2022)

• Record Type: Journal Article
• Authors: Sun, Q.; Chen, X.; Xie, J.; Huang, C.; Xu, X.; Tu, J.; Shen, C.; Jin, Y.; Zhang, K.; Chen, F.; Zhu, T.; Zhao, X.; Cheng, J.
• Is Part Of: Materials today nano. Volume 19(2022)
• Publication Date: 2022-08
• Subjects: LATP-Coated LiCoO2 -- Ultrathin garnet-based membrane -- In-situ polymerization -- Quasi-solid-state electrolyte -- Lithium metal battery; LATP Li1.3Al0.3Ti1.7(PO4)3; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Nanoscience; Nanotechnology -- Periodicals; Periodicals; Periodical; Electronic journals; Electronic journals; 620.5
• DOI: 10.1016/j.mtnano.2022.100235
• Languages: English
• ISSNs: 2588-8420

Abstract

Abstract: Garnet-type Li7 La3 Zr2 O12 (LLZO) ceramics has been considered as an ideal solid-state electrolyte for Li metal cells because of its high ionic conductivity and relatively stable interface with Li. However, it is electrochemically incompatible with some high-voltage cathodes, e.g. LiCoO2 . In this work, a nanoscale Li1.3 Al0.3 Ti1.7 (PO4 )3 (LATP) fast ion conductor was coated on LiCoO2 (only 1 wt% LATP), bringing obviously enhanced interfacial compatibility with a composite electrolyte composed of Al, Nb-codoped LLZO and polyethylene oxide (PEO). A free-standing, flexible and ultrathin (20 μm) electrolyte membrane was successfully fabricated by a facile and scalable route, even though with a high ceramics content (67 wt%). Quasi-solid-state coin and pouch-type Li cells were assembled with the LATP-coated LiCoO2 cathode, free-standing composite electrolyte and Li anode, together with soft interface modification by in-situ polymerization. The cells show stable cycling due to combined factors of enhanced electrode/electrolyte compatibility, ultrathin nature of the electrolyte membrane and the in-situ built soft interface. The pouch cells can be cycled for 300 cycles at 0.3 C and 60 °C with 80% retention. The pouch cells can endure abuse tests of bending, cutting and nail penetration. At a practical LiCoO2 loading of 3 mAh cm −2, the Li|LiCoO2 pouch cell still shows stable cycling with 90% retention after 100 cycles at 60 °C (0.2 C charge/0.5 C discharge). This work provides a practical method to fabricate high-performance solid-state Li cells. Graphical abstract: Image 1 Highlights: LATP coating on LiCoO2 improves interfacial stability with garnet/PEO electrolyte. Ultrathin garnet/PEO film of 20 μm was prepared by a facile and scalable route. Li|LiCoO2 pouch cell with QCE shows 90% retention after 100 cycles at 60 °C. Li|LiCoO2 pouch cells pass abuse tests of folding, cutting and nail penetration.