Interphase Engineering Enabled All-Ceramic Lithium Battery Fudong Han, Jie Yue, Cheng Chen, Ning Zhao, Xiulin Fan, Zhaohui Ma, Tao Gao, Fei Wang, Xiangxin Guo, Chunsheng Wang  Joule  Volume 2, Issue 3, Pages 497-508 (March 2018) DOI: 10.1016/j.joule.2018.02.007 Copyright © 2018 Elsevier Inc. Terms and Conditions

Joule 2018 2, 497-508DOI: (10.1016/j.joule.2018.02.007) Copyright © 2018 Elsevier Inc. Terms and Conditions

Figure 1 Schematics of the Interphase-Engineered All-Ceramic Cathode/Electrolyte A thin layer of Li2CO3 (3 nm) was artificially coated on LCO because the spontaneously formed Li2CO3 on LCO is too thin. The Li2CO3-coated LCO (LCO@Li2CO3) was then mixed with a spontaneously Li2CO3-coated LLZO (LLZO@Li2CO3), and Li2.3C0.7B0.3O3 solder to make a cathode composite. The cathode composite was then coated on an LLZO ceramic pellet, which was also spontaneously coated by Li2CO3. After sintering at 700°C, Li2.3C0.7B0.3O3 will melt, and react with the Li2CO3 coatings on both LLZO and LCO to form Li2.3−xC0.7+xB0.3−xO3 (LCBO) interphase. Joule 2018 2, 497-508DOI: (10.1016/j.joule.2018.02.007) Copyright © 2018 Elsevier Inc. Terms and Conditions

Figure 2 Characterization of Li2CO3 Coatings on LLZO and LCO (A and B) SEM (A) and TEM (B) images of the LLZO@Li2CO3. (C) SEM image and elemental mappings of C and Zr (C) of the LLZO@Li2CO3. (D and E) SEM (D) and TEM (E) images of the as-synthesized LCO. (F and G) SEM (F) and TEM (G) images of the LCO@Li2CO3. (H–J) XRD (H), Raman (I), and XPS (J) of the as-synthesized LCO, LCO@Li2CO3, and LLZO@Li2CO3, respectively. The Raman spectrum of Li2CO3 was also included in (I). Joule 2018 2, 497-508DOI: (10.1016/j.joule.2018.02.007) Copyright © 2018 Elsevier Inc. Terms and Conditions

Figure 3 Characterization of the Interphase-Engineered All-Ceramic Cathode/Electrolyte (A) XRD of the composites of Li2.3C0.7B0.3O3 + LCO@Li2CO3 (12:58 in weight), Li2.3C0.7B0.3O3 + LLZO@Li2CO3 (12:30 in weight), and Li2.3C0.7B0.3O3 + LLZO@Li2CO3 + LCO@Li2CO3 (12:30:58 in weight) after sintering at 700°C for 1 hr in air. These composites were ball-milled with the corresponding weight ratio and pressed into pellets before sintering. (B and C) SEM images of cross-section (B) and top surface (C) of the cathode composite (Li2.3C0.7B0.3O3 + LLZO@Li2CO3 + LCO@Li2CO3) coated on an LLZO pellet before sintering. (D and E) SEM images of cross-section (D) and top surface (E) of the cathode composite coated on an LLZO pellet after sintering at 700°C for 1 hr in air. (F–I) High-magnification cross-section SEM image (F) and elemental mappings of Zr (G), Co (H), and B (I) of the cathode composite after sintering at 700°C for 1 hr in air. Joule 2018 2, 497-508DOI: (10.1016/j.joule.2018.02.007) Copyright © 2018 Elsevier Inc. Terms and Conditions

Figure 4 Electrochemical Performance of All-Ceramic Li/LLZO/LCO Cells (A) Charge/discharge profiles of the interphase-engineered all-ceramic Li/LLZO/LCO cell for the first three cycles at 0.05 C at 100°C. (B) Charge/discharge profiles of the interphase-engineered all-ceramic Li/LLZO/LCO cell at different rates from 0.05 C to 1 C at 100°C. Note that the profiles at five different C rates were obtained from five fresh cells after one activation cycle at 0.05 C. (C) Rate performance of the interphase-engineered all-ceramic Li/LLZO/LCO cell at 100°C. Note that the capacities at five different C rates were obtained from five fresh cells with each cell represented by one color. (D) Cycling performance of the interphase-engineered all-ceramic Li/LLZO/LCO cell at 0.05 C at 100°C. The cycling performances of all-ceramic Li/LLZO/LCO cells with the cathode composites consisting of uncoated LCO (LCO + Li2.3C0.7B0.3O3 + LLZO@Li2CO3) and uncoated LLZO (LCO@Li2CO3 + Li2.3C0.7B0.3O3 + LLZO) were also included. (E) Charge/discharge profiles of the interphase-engineered all-ceramic Li/LLZO/LCO cell for the first three cycles at 0.05 C at 25°C. (F) Cycling performance of the interphase-engineered all-ceramic Li/LLZO/LCO cell at 0.05 C at 25°C. The specific capacity was calculated based on the weight of LCO in the cathode composite. Joule 2018 2, 497-508DOI: (10.1016/j.joule.2018.02.007) Copyright © 2018 Elsevier Inc. Terms and Conditions