Elastic-Viscoplastic Mechanics of Lithium in a Standard Dry Room

Author(s):  
Lara L. Dienemann ◽  
Anil Saigal ◽  
Michael A. Zimmerman

Abstract In electrochemical-mechanical modeling of solid-state batteries, there is a lack of understanding of the mechanical parameters and mode of deformation of lithium metal. Understanding these characteristics is crucial for predicting the propagation of lithium dendrites through the electrolyte — a key element of battery safety. Past theories have assumed linear elastic as well as elastic-plastic deformation of lithium. However, recent experiments show that the primary mode of deformation is creep. This study replicates the temperature dependent mechanical experiments but inside an industrial dry room, where battery cells are manufactured at high volume. Furthermore, this work conducts time dependent studies — also inside the dry room — to gain insight of the large deformation theories of lithium metal. The results confirm the activation energy, which dictates the creep mechanism, is correlated to core diffusion rather than lattice diffusion.

Author(s):  
Lara Dienemann ◽  
Anil Saigal ◽  
Michael A Zimmerman

Abstract Commercialization of energy-dense lithium metal batteries relies on stable and uniform plating and stripping on the lithium metal anode. In electrochemical-mechanical modeling of solid-state batteries, there is a lack of consideration of specific mechanical properties of battery-grade lithium metal. Defining these characteristics is crucial for understanding how lithium ions plate on the lithium metal anode, how plating and stripping affect deformation of the anode and its interfacing material, and whether dendrites are suppressed. Recent experiments show that the dominant mode of deformation of lithium metal is creep. This study measures the time and temperature dependent mechanics of two thicknesses of commercial lithium anodes inside an industrial dry room, where battery cells are manufactured at high volume. Furthermore, a directional study examines the anisotropic microstructure of 100 µm thick lithium anodes and its effect on bulk creep mechanics. It is shown that these lithium anodes undergo plastic creep as soon as a coin cell is manufactured at a pressure of 0.30 MPa, and achieving thinner lithium foils, a critical goal for solid-state lithium batteries, is correlated to anisotropy in both lithium's microstructure and mechanical properties.


2021 ◽  
Author(s):  
Jordi Sastre ◽  
Moritz Futscher ◽  
Lea Pompizi ◽  
Abdessalem Aribia ◽  
Agnieszka Priebe ◽  
...  

Abstract Lithium metal dendrites have become a roadblock in the realization of next-generation solid-state batteries with lithium metal as high-capacity anode. The presence of surface and bulk inhomogeneities with non-negligible electronic conductivity in crystalline electrolytes such as the lithium garnet Li7La3Zr2O12 (LLZO) facilitates the growth of lithium filaments, posing a critical safety risk. Here we explore the amorphous phase of LLZO (aLLZO) as a lithium dendrite shield owing to its grain-boundary-free microstructure, stability against metallic lithium, and high electronic insulation. We demonstrate that by tuning the lithium stoichiometry in sputtered aLLZO films, the ionic conductivity can be increased up to 10-7 S cm-1 while retaining an ultralow electronic conductivity of 10-14 S cm-1. In Li/aLLZO/Li symmetric cells, plating-stripping results in no degradation of the films and current densities up to 3.2 mA cm-2 can be applied with no signs of lithium penetration. The defect-free and conformal nature of the films enables microbatteries with an electrolyte thickness as low as 70 nm, which withstand charge-discharge at 0.2 mA cm-2 for over 500 cycles. Finally, we demonstrate that the application of aLLZO as a coating on crystalline LLZO lowers the interface resistance and significantly impedes the formation of lithium dendrites, increasing the critical current density of a symmetric cell up to 1.3 mA cm-2 at room temperature and without external pressure. The effectiveness of the amorphous Li-La-Zr-O as lithium dendrite blocking layer can accelerate the development of more powerful and safer solid-state batteries.


2021 ◽  
Author(s):  
Jordi Sastre ◽  
Moritz H. Futscher ◽  
Lea Pompizi ◽  
Abdessalem Aribia ◽  
Agnieszka Priebe ◽  
...  

Lithium metal dendrites have become a roadblock in the realization of next-generation solid-state batteries with lithium metal as high-capacity anode. The presence of surface and bulk inhomogeneities with non-negligible electronic conductivity in crystalline electrolytes such as the lithium garnet Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub> (LLZO) facilitates the growth of lithium filaments, posing a critical safety risk. Here we explore the amorphous phase of LLZO (aLLZO) as a lithium dendrite shield owing to its grain-boundary-free microstructure, stability against metallic lithium, and high electronic insulation. We demonstrate that by tuning the lithium stoichiometry in sputtered aLLZO films, the ionic conductivity can be increased up to 10<sup>-7</sup> S cm<sup>-1</sup> while retaining an ultralow electronic conductivity of 10<sup>-14</sup> S cm<sup>-1</sup>. In Li/aLLZO/Li symmetric cells, plating-stripping results in no degradation of the films and current densities up to 3.2 mA cm<sup>-2</sup> can be applied with no signs of lithium penetration. The defect-free and conformal nature of the films enables microbatteries with an electrolyte thickness as low as 70 nm, which withstand charge-discharge at 0.2 mA cm<sup>-2</sup> for over 500 cycles. Finally, we demonstrate that the application of aLLZO as a coating on crystalline LLZO lowers the interface resistance and significantly impedes the formation of lithium dendrites, increasing the critical current density of a symmetric cell up to 1.3 mA cm<sup>-2</sup> at room temperature and without external pressure. The effectiveness of the amorphous Li-La-Zr-O as lithium dendrite blocking layer can accelerate the development of more powerful and safer solid-state batteries.<div></div>


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Jordi Sastre ◽  
Moritz H. Futscher ◽  
Lea Pompizi ◽  
Abdessalem Aribia ◽  
Agnieszka Priebe ◽  
...  

AbstractLithium dendrites have become a roadblock in the realization of solid-state batteries with lithium metal as high-capacity anode. The presence of surface and bulk defects in crystalline electrolytes such as the garnet Li7La3Zr2O12 (LLZO) facilitates the growth of these hazardous lithium filaments. Here we explore the amorphous phase of LLZO as a lithium dendrite shield owing to its grain-boundary-free microstructure, stability against lithium metal, and high electronic insulation. By tuning the lithium stoichiometry, the ionic conductivity can be increased by 4 orders of magnitude while retaining a negligible electronic conductivity. In symmetric cells, plating-stripping shows no signs of lithium penetration up to 3.2 mA cm−2. The dense conformal nature of the films enables microbatteries with an electrolyte thickness of only 70 nm, which can be cycled at 10C for over 500 cycles. The application of this material as a coating on crystalline LLZO lowers the interface resistance and increases the critical current density. The effectiveness of the amorphous Li-La-Zr-O as dendrite blocking layer can accelerate the development of better solid-state batteries.


2022 ◽  
Vol 521 ◽  
pp. 230921
Author(s):  
Yuncai Chen ◽  
Yidong Jiang ◽  
Shang-Sen Chi ◽  
Haw Jiunn Woo ◽  
Kai Yu ◽  
...  

2021 ◽  
Vol MA2021-01 (5) ◽  
pp. 291-291
Author(s):  
Alvaro Masias ◽  
Mihir Upadhye ◽  
Jeff Sakamoto

2021 ◽  
Vol 405 ◽  
pp. 126808
Author(s):  
Danqing Jin ◽  
Kang Hu ◽  
Rui Hou ◽  
Huan Shang ◽  
Xueyou Wang ◽  
...  

2020 ◽  
Vol 6 (10) ◽  
pp. eaaz3112 ◽  
Author(s):  
Huadong Yuan ◽  
Jianwei Nai ◽  
He Tian ◽  
Zhijin Ju ◽  
Wenkui Zhang ◽  
...  

The lithium metal anode (LMA) is considered as a promising star for next-generation high-energy density batteries but is still hampered by the severe growth of uncontrollable lithium dendrites. Here, we design “spansules” made of NaMg(Mn)F3@C core@shell microstructures as the matrix for the LMA, which can offer a long-lasting release of functional ions into the electrolyte. By the assistance of cryogenic transmission electron microscopy, we reveal that an in situ–formed metal layer and a unique LiF-involved bilayer structure on the Li/electrolyte interface would be beneficial for effectively suppressing the growth of lithium dendrites. As a result, the spansule-modified anode affords a high Coulombic efficiency of 98% for over 1000 cycles at a current density of 2 mA cm−2, which is the most stable LMA reported so far. When coupling this anode with the Li[Ni0.8Co0.1Mn0.1]O2 cathode, the practical full cell further exhibits highly improved capacity retention after 500 cycles.


2020 ◽  
Vol 3 (9) ◽  
pp. 936-945 ◽  
Author(s):  
Qing Xuan Shi ◽  
Xin Guan ◽  
Hui Jie Pei ◽  
Chen Chang ◽  
Hao Qu ◽  
...  

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