High‐Efficacy and Polymeric Solid‐Electrolyte Interphase for Closely Packed Li Electrodeposition

Abstract

The industrial application of lithium metal anode requires less side reaction between active lithium and electrolyte, which demands the sustainability of the electrolyte‐induced solid‐electrolyte interface. Here, through a new diluted lithium difluoro(oxalato)borate‐based (LiDFOB) high concentration electrolyte system, it is found that the oxidation behavior of aggregated LiDFOB salt has a great impact on solid‐electrolyte interphase (SEI) formation and Li reversibility. Under the operation window of Cu/LiNi0.8Co0.1Mn0.1O2 full cells (rather than Li/Cu configuration), a polyether/coordinated borate containing solid‐electrolyte interphase with inner Li2O crystalline can be observed with the increasing concentration of salt, which can be ascribed to the reaction between aggregated electron‐deficient borate species and electron‐rich alkoxide SEI components. The high Li reversibility (99.34%) and near‐theoretical lithium deposition enable the stable cycling of LiNi0.8Co0.1Mn0.1O2/Li cells (N/P < 2, 350 Wh kg−1) under high cutoff voltage condition of 4.6 V and lean electrolyte condition (E/C ≈ 3.2 g Ah−1).

Practical production of heteroatom-bridged and mixed amorphous–crystalline silicon for stable and fast-charging batteries

“…4d). 49,50 Compared to the result of the as-prepared material in Fig. 3i, LiBO 2 at 191.1 eV in the cycled electrode substituted a portion of B–O and B–O–Si by electrochemical participation (Fig.…”

Modified lithium metal anodeviaanion-planting protection mechanisms for dendrite-free long-life lithium metal batteries

“…LiDFOB and LiNO 3 salts with a higher potential for cathodic decomposition are well-known agents for constructing a stable SEI, leading to a more controlled Li deposition. 44,46,52,60 As shown in Fig. 5a and S13,† three obvious cathodic peaks emerged at 1.5, 0.75, and 0.5 V, which could be mainly ascribed to the reduction of LiTFSI and LiNO 3 .…”

“…8b). 44,46,64 The significant increase in the proportion of Li–F̲ in DDDF@Li with the concomitant products like B–F and C–F species should be attributed to the decomposition of fluorinated anions (TFSI − and DFOB − ) (Fig. 8b-DDDF).…”

A nonflammable phosphate-based localized high-concentration electrolyte for safe and high-voltage lithium metal batteries

“…36,44 In order to address these issues, the localized high-concentration electrolytes (LHCEs) have been achieved by introducing inert cosolvents as diluting agents in the electrolytes. 8,10,41,44–47 Such diluting agents, for example fluorinated ethers, do not dissolve Li salts while maintain the advantages of HCEs.…”