Promoting Homogeneous Interfacial Li⁺ Migration by Using a Facile N₂ Plasma Strategy for All‐Solid‐State Lithium‐Metal Batteries

Abstract

Hybrid solid electrolytes (HSEs) with satisfactory ionic conductivities, good flexibilities, and ideal interface compatibilities are crucial for the development of all‐solid‐state lithium‐metal batteries. However, Li dendrites and sluggish interfacial Li+ transfer dynamics between the Li metal and HSEs restrict practical applications. Herein, a facile strategy is proposed to promote homogeneous interfacial Li+ migration by modifying HSEs by using nitrogen plasma. N2 plasma not only decreases the crystallinity and glass transition temperature of HSE but also in‐situ generates an ultra‐stable and conductive Li3N layer on the HSE surface. This conductive layer promotes interfacial Li+ migration and favorable wettability, thus effectively improving Li+ transfer dynamics and homogeneous deposition. Therefore, a HSE modified by N2 plasma for 10 s exhibits a low interfacial impedance of 26.5 Ω cm−2 and a high Li+ conductivity of 7.35 × 10−5 S cm−1 at 30 °C. Moreover, a symmetric Li|HSE|Li battery exhibits a stable plating/stripping capability without Li dendrite growth at a current density of 0.1 mA cm−2 during continuous operation over 1000 h. In addition, an all‐solid‐state Li|HSE|LiFePO4 battery exhibits an initial specific capacity of 145.0 mAh g−1 at 1 C with a high capacity retention of 92.4% (134.0 mAh g−1) after 140 cycles.

A highly conductive and stable hybrid solid electrolyte for high voltage lithium metal batteries

“…As observed in Fig. S10,† the t Li + of the P(VDF-HFP) electrolyte is 0.27, 41 and the t Li + of P(VDF-HFP)-50LATP HSE was further increased to 0.48 after the LATP particles were added into the P(VDF-HFP) electrolyte owing to the high Li + transfer number of LATP inorganic particles (theoretical t Li + = 1). The P(VDF-HFP)-Li 10 electrolyte with a Li + transmission channel has a higher lithium transference number (0.51) than the P(VDF-HFP)-50LATP HSE.…”

“…Fig. 3a shows the temperature dependence of the Li + conductivity of different HSEs (with LiTFSI), and the 15,16,33,37,[39][40][41][42][43][44][45][46][47] Our work exhibits high voltage stability and ionic conductivity (for details see Table S4 The lithium transference number (t Li…”

“…(c) Current-time curves following DC polarization of P(VDF-HFP)-Li 10 -50LATP, under an applied voltage of 10 mV, and the insets are the AC impedance spectra of the electrolyte. (d) Comparison of the electrochemical performance of HSEs in recent studies (a-i) 15,16,33,37,[39][40][41][42][43][44][45][46][47]. Our work exhibits high voltage stability and ionic conductivity (for details see TableS4†).…”

Enhancement of interfacial sodium ion transport stability in quasi-solid-state sodium-ion batteries using polyethylene glycol

“…[20][21][22] In our previous work, the in situ synthesis of metal nitrides by nitrogen plasma modification of PVDF-HFP also effectively promoted the uniform deposition of metal anodes. 23 In a recent study, Dou et al found that the framework with ''sodiophilic'' sites/functional groups could guide the gradient deposition of sodium and promote the growth of sodium from bottom to top, which can ensure a continuous and sufficient supply of Na + for the entire sodium anode, inhibit the growth of sodium dendrites, and improve the stability of the anode interface. 24 Therefore, improving the wettability of the QSE surface to metallic sodium by introducing ''sodiophilic'' sites/functional groups is a facile strategy to inhibit the growth of sodium dendrites.…”

Dual Vertically Aligned Electrode‐Inspired High‐Capacity Lithium Batteries

“…[ 19 , 20 , 21 ] Third, employing solid inorganic or polymer electrolytes can partly relieve several safety issues, such as leakage, poor chemical stability, and flammability for liquid electrolytes. [ 22 , 23 , 24 ] Finally, constructing three‐dimensional (3D) conductive scaffolds as the host matrix can not only regulate Li plating and accommodate volume changes but also decrease the local current density due to the enlarged surface area. [ 25 , 26 , 27 ] These strategies have contributed to improving the performance of LMAs; however, the problems of dendrite growth and poor cycling stability remain major concerns in the case of high current density and high areal capacity operation of LMAs.…”