The effect of garnet content on the microstructure and electrochemical properties of PEO/garnet composite electrolyte

• Published in: Solid state ionics 2024-07, Vol.410, p.116527, Article 116527
• Main Authors: Xie, Wenfei, Gong, Zhinan, Li, Jie, Yu, Shiyu, Wei, Yaqing, Li, De, Chen, Yong, Chen, Daming
• Format: Article
• Language: English
• Subjects: Composite solid electrolyte; Electrochemical performance; LGLZO; Lithium-ion battery; PEO
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2024.116527

Solid-state lithium-metal batteries are one of the best candidates for next-generation energy storage devices. However, their applications are hindered by the low ionic conductivity at room temperature and the inadequate interfacial compatibility of solid-state electrolytes (SSEs). Hence, an organic/inorganic composite solid electrolyte (CSE) of Li6.25Ga0.25La3Zr2O12 (LGLZO)/polyethylene oxide (PEO) films were constructed. It's found that the crystallinity of CSE is significantly reduced and the ionic conductivity is increased to 3.57 × 10−4 S cm−1 at room temperature, which is about 60 times higher than that of the pure PEO.And the interfacial impedance is 243.84 Ω cm2, electrochemical window of 5.1 V. The assembled Li symmetric battery has excellent cycling stability more than 1000 h at 0.15 mA cm−2. The Li/PEO-LiTFSI-60 wt% LGLZO/LiFePO4 (LFP) all solid-state lithium batteries (ASSLBs) also delivers superior electrochemical performances. This work can provide a reference for the development and real-world implementation of ASSLBs at room temperature. [Display omitted] •The relationship between filler content and sample properties was investigated by modulating the amount of LGLZO.•The ionic conductivity of LGLZO/PEO electrolyte was increased to 3.57×10-4 S cm-1, which is 60 times that of PEO. The ionof LGLZO/PEO electrolyte was increased to 3.57×10−4 S cm−1, which is 60 times that of PEO.•The CCD of Li|PEO/LGLZO|Li reached 0.8 mA cm−2, and it could cycle for over 1000 hours at current density of 0.15 mA cm−2.•Li|PEO/LGLZO|LFP has discharge specific capacity of 135 mAh g-1 and capacity retention rate of 97.26% after 80 cycles.