An ultrastable lithium metal anode enabled by designed metal fluoride spansules

Abstract

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.

Exploiting the Degradation Mechanism of NCM523Graphite Lithium‐Ion Full Cells Operated at High Voltage

“…In this context, Yuan et al also reported that certain metal species (e. g., metal fluorides) can have a significant impact on the uniformity of Li metal deposition and dissolution in Li metal cells. [63] The different impacts of various dissolved TMs on the morphology of Li metal deposits on Li metal has been also reported by Betz et al [40] Overall, these studies give a first indication of the significant impact of TMs on the homogeneity and uniformity of Li metal deposits, however, further studies are needed to clearly understand the impact of individual TMs and specific TM species.…”

“…In this context, Yuan et al. also reported that certain metal species (e. g., metal fluorides) can have a significant impact on the uniformity of Li metal deposition and dissolution in Li metal cells [63] . The different impacts of various dissolved TMs on the morphology of Li metal deposits on Li metal has been also reported by Betz et al [40] .…”

In Situ Construction of a LiF‐Enriched Interface for Stable All‐Solid‐State Batteries and its Origin Revealed by Cryo‐TEM

“…[1,2] Nevertheless, the large-scale application of LMBs is inherently inhibited by the uncontrollable growth of Li dendrite on Li anode. [3,4] The typical issue is addressed through various strategies, for example, the interfacial SEI engineering, [5,6] stable hosts construction, [7,8] and solid electrolyte design. [9,10] Among the strategies, the solid state electrolytes, particularly the solid polymer electrolytes (SPEs) for LMBs, have gained tremendous interest for many decades.…”

Water based synthesis of highly conductive GaxLi7−3xLa3Hf2O12 garnets with comparable critical current density to analogous GaxLi7−3xLa3Zr2O12 systems

“…However, modern day LIBs use liquid-based electrolytes that enable propagation of lithium dendrites, and so pose significant safety concerns with the use of a Li metal anode 3 . Despite intensive research to prevent dendritic growth [4][5][6][7][8][9][10] , a practical solution to eliminate this issue remains elusive. Furthermore, these electrolytes are flammable, toxic, non-renewable and often have a limited electrochemical window (preventing use of high V cathode materials), hence they are not ideal for the high energy demands of modern-day society 2,[11][12][13][14] .…”