The Challenge of Lithium Metal Anodes for Practical Applications

Abstract

Lithium metal anodes are considered as the “Holy Grail” to achieve high energy density of rechargeable batteries. In the past 50 years, enormous progress has been made to solve the long‐term disturbing issues of poor safety and cyclic stability for lithium metal batteries (LMBs). However, there is still a long distance to realize the application of LMBs. In this review, the mechanisms of dendrite growth and solid electrolyte interphase (SEI) properties are first summarized to figure out the impact factors of the two issues. Advanced strategies are subsequently discussed by regulating different impact factors like current density, overpotential, and interfacial properties. To promote the practical application of LMBs, it is concluded that future research should focus on constructing robust SEI layers, either in liquid electrolytes or solid‐state electrolytes. Moreover, promising research directions and development suggestions are also provided in this review.

Nonflammable quasi-solid-state electrolyte for stable lithium-metal batteries

“…NASICONtype Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP), garnet-type Li 7 La 3 Zr 2 O 12 (LLZO) and sulde Li 3 PS 7 (LPS) are the typical inorganic electrolytes. 26 SIEs usually exhibit a high ionic conductivity between 10 À4 -10 À3 S cm À1 , and the ionic conductivity of some suldes can even be comparable to those of traditional liquid electrolytes. [27][28][29] However, these electrolytes are usually unstable at storage, e.g., Li 2 CO 3 forms on the surface of LLZO and H 2 S is produced when LPS is exposed to air.…”

Thermal and Electrochemical Properties of Solid Polymer Electrolytes Prepared via Lithium Salt-Catalyzed Epoxide Ring Opening Polymerization

“…Namely, polymer chains in PDMS-containing compounds tend to be very mobile which confers a low T g and a high Coulombic efficiency [76,79]. However, as silicone-based reagents tend to be liquids under ambient conditions and have relatively low ionic conductivity, these must be co-polymerized to produce viable electrolyte materials [76,80]. The real advantage of incorporating silicone-based polymers into solid electrolytes is that they are highly compatible with lithium-based electrodes.…”

“…The real advantage of incorporating silicone-based polymers into solid electrolytes is that they are highly compatible with lithium-based electrodes. The Si-O-Si polymer backbone makes these materials highly flexible and lithophilic which gives them a high affinity for lithium anodes [76,80]. In fact, nano-scale PDMS-based coatings are able to respond to changes in the lithium anode surface that occur during cycling which protects the solid electrolyte interface from damage and improves the Coulombic efficiency of the device [80].…”

“…The Si-O-Si polymer backbone makes these materials highly flexible and lithophilic which gives them a high affinity for lithium anodes [76,80]. In fact, nano-scale PDMS-based coatings are able to respond to changes in the lithium anode surface that occur during cycling which protects the solid electrolyte interface from damage and improves the Coulombic efficiency of the device [80]. In terms of the cathode, the high oxidative stability of siloxanes means that these materials are compatible with a wide range of cathode materials [76].…”

Finite-pulse waves for efficient suppression of evolving mesoscale dendrites in rechargeable batteries

“…which resembles the flux from the linear concentration distribution throughout the entire span of double layer and has been expressed as the critical current density, where the electrode concentration goes to zero. [52,53] Therefore the homogenized relaxation time would have the following span:…”