Reclaiming Inactive Lithium with a Triiodide/Iodide Redox Couple for Practical Lithium Metal Batteries

Abstract

High-energy-density lithium (Li)m etal batteries suffer from as hort lifespan owing to apparently ceaseless inactive Li accumulation, which is accompanied by the consumption of electrolyte and active Li reservoir,s eriously deteriorating the cyclability of batteries.H erein, at riiodide/ iodide (I 3 À /I À )redox couple initiated by stannic iodide (SnI 4 )is demonstrated to reclaim inactive Li. The reduction of I 3 À converts inactive Li into soluble LiI, which then diffuses to the cathode side.T he oxidation of LiI by the delithiated cathode transforms cathode into the lithiation state and regenerates I 3 À ,r eclaiming Li ion from inactive Li. The regenerated I 3 À engages the further redox reactions.F urthermore,t he formation of Sn mitigates the corrosion of I 3 À on active Li reservoir sacrificially.I nw orking Li j Li-Ni 0.5 Co 0.2 Mn 0.3 O 2 batteries,t he accumulated inactive Li is significantly reclaimed by the reversible I 3 À /I À redox couple, improving the lifespan of batteries by twice.This work initiates ac reative solution to reclaim inactive Li for prolonging the lifespan of practical Li metal batteries.

Liquid electrolyte chemistries for solid electrolyte interphase construction on silicon and lithium-metal anodes

“…The above rejuvenation mechanism has been extensively exploited to enhance the long-term reversibility of lithium-metal anodes. 173,256,257 In addition, SEI stability can be improved by forming a Li 3 N-rich SEI through the rejuvenation of Li 2 O, which is unavoidably generated by the decomposition of LiNO 3 (LiNO 3 + 8Li + + 8e − → Li 3 N + 3Li 2 O). 103,258 This allows the formation of SEIs with superb ionic conductivity due to the increased content of highly ion-conductive Li 3 N (∼10 −3 S cm −1 ) and enables epitaxy-like planar lithium deposition on lithium-metal anodes, thereby enhancing SEI stability.…”

Recent Advances and Opportunities in Reactivating Inactive Lithium in Batteries

“…Moreover, it has been demonstrated that stannic iodide can not only reactivate inactive lithium but also mitigate the corrosion caused by I 3 À on active lithium. [46] These approaches effectively rejuvenate electrochemically inactive lithium in both the inactive SEI and electrically "isolated lithium" metal debris. The I 3 À additive spontaneously removes inactive lithium sources, resulting in the formation of soluble LiI and IO 3 À species.…”

Lithiophilic SiO2 nanoparticle pillared MXene nanosheets for stable and dendrite-free lithium metal anodes

“…7,8 Many strategies have been developed to mitigate Li dendrite formation and improve the performance of Li-metal batteries, including construction of an articial SEI, 9-13 modication of a separator, [14][15][16] designing novel current collectors [17][18][19][20] and tuning the composition of the electrolyte. [21][22][23] Among them, constructing three-dimensional (3D) electrodes is an effective approach to homogenize Li ion ux, prevent Li dendrite growth and improve the stability of Li-metal batteries. The 3D electrode structure can regulate the kinetics of Li deposition, such as shortening the transport path of Li ions, preventing charge accumulation, and promoting the uniform nucleation and growth of Li metal.…”