共查询到20条相似文献,搜索用时 31 毫秒
1.
Xue‐Qiang Zhang Tao Li Bo‐Quan Li Rui Zhang Peng Shi Chong Yan Jia‐Qi Huang Qiang Zhang 《Angewandte Chemie (International ed. in English)》2020,59(8):3252-3257
High‐energy‐density Li metal batteries suffer from a short lifespan under practical conditions, such as limited lithium, high loading cathode, and lean electrolytes, owing to the absence of appropriate solid electrolyte interphase (SEI). Herein, a sustainable SEI was designed rationally by combining fluorinated co‐solvents with sustained‐release additives for practical challenges. The intrinsic uniformity of SEI and the constant supplements of building blocks of SEI jointly afford to sustainable SEI. Specific spatial distributions and abundant heterogeneous grain boundaries of LiF, LiNxOy, and Li2O effectively regulate uniformity of Li deposition. In a Li metal battery with an ultrathin Li anode (33 μm), a high‐loading LiNi0.5Co0.2Mn0.3O2 cathode (4.4 mAh cm?2), and lean electrolytes (6.1 g Ah?1), 83 % of initial capacity retains after 150 cycles. A pouch cell (3.5 Ah) demonstrated a specific energy of 340 Wh kg?1 for 60 cycles with lean electrolytes (2.3 g Ah?1). 相似文献
2.
Qian-Kui Zhang Shu-Yu Sun Dr. Ming-Yue Zhou Li-Peng Hou Jia-Lin Liang Shi-Jie Yang Dr. Bo-Quan Li Dr. Xue-Qiang Zhang Prof. Jia-Qi Huang 《Angewandte Chemie (International ed. in English)》2023,62(42):e202306889
The stability of high-energy-density lithium metal batteries depends on the uniformity of solid electrolyte interphase (SEI) on lithium metal anodes. Rationally improving SEI uniformity is hindered by poorly understanding the effect of structure and components of SEI on its uniformity. Herein, a bilayer structure of SEI formed by isosorbide dinitrate (ISDN) additives in localized high-concentration electrolytes was demonstrated to improve SEI uniformity. In the bilayer SEI, LiNxOy generated by ISDN occupies top layer and LiF dominates bottom layer next to anode. The uniformity of lithium deposition is remarkably improved with the bilayer SEI, mitigating the consumption rate of active lithium and electrolytes. The cycle life of lithium metal batteries with bilayer SEI is three times as that with common anion-derived SEI under practical conditions. A prototype lithium metal pouch cell of 430 Wh kg−1 undergoes 173 cycles. This work demonstrates the effect of a reasonable structure of SEI on reforming SEI uniformity. 相似文献
3.
Jiale Fu Dr. Xiao Ji Dr. Ji Chen Dr. Long Chen Prof. Xiulin Fan Prof. Daobin Mu Prof. Chunsheng Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22378-22385
The electrolytes in lithium metal batteries have to be compatible with both lithium metal anodes and high voltage cathodes, and can be regulated by manipulating the solvation structure. Herein, to enhance the electrolyte stability, lithium nitrate (LiNO3) and 1,1,2,2-tetrafuoroethyl-2′,2′,2′-trifuoroethyl(HFE) are introduced into the high-concentration sulfolane electrolyte to suppress Li dendrite growth and achieve a high Coulombic efficiency of >99 % for both the Li anode and LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes. Molecular dynamics simulations show that NO3− participates in the solvation sheath of lithium ions enabling more bis(trifluoromethanesulfonyl)imide anion (TFSI−) to coordinate with Li+ ions. Therefore, a robust LiNxOy−LiF-rich solid electrolyte interface (SEI) is formed on the Li surface, suppressing Li dendrite growth. The LiNO3-containing sulfolane electrolyte can also support the highly aggressive LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode, delivering a discharge capacity of 190.4 mAh g−1 at 0.5 C for 200 cycles with a capacity retention rate of 99.5 %. 相似文献
4.
Yu Wang Bochun Liang Jiaxiong Zhu Geng Li Qing Li Ruquan Ye Jun Fan Chunyi Zhi 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302583
Constructing a reliable solid-electrolyte interphase (SEI) is imperative for enabling highly reversible zinc metal (Zn0) electrodes. Contrary to conventional “bulk solvation” mechanism, we found the SEI structure is dominated by electric double layer (EDL) adsorption. We manipulate the EDL adsorption and Zn2+ solvation with ether additives (i.e. 15-crown-5, 12-crown-4, and triglyme). The 12-crown-4 with medium adsorption on EDL leads to a layer-structured SEI with inner inorganic ZnFx/ZnSx and outer organic C−O−C components. This structure endows SEI with high rigidness and strong toughness enabling the 100 cm2 Zn||Zn pouch cell to exhibit a cumulative capacity of 4250 mAh cm−2 at areal-capacity of 10 mAh cm−2. More importantly, a 2.3 Ah Zn||Zn0.25V2O5⋅n H2O pouch cell delivers a recorded energy density of 104 Wh Lcell−1 and runs for >70 days under the harsh conditions of low negative/positive electrode ratio (2.2 : 1), lean electrolyte (8 g Ah−1), and high-areal-capacity (≈13 mAh cm−2). 相似文献
5.
Yifeng Cheng Zhijie Wang Jinbiao Chen Yuanmao Chen Xi Ke Duojie Wu Qing Zhang Yuanmin Zhu Xuming Yang Meng Gu Zaiping Guo Zhicong Shi 《Angewandte Chemie (International ed. in English)》2023,62(30):e202305723
A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long-term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst-derived artificial SEI layer with an ordered polyamide-lithium hydroxide (PA-LiOH) bi-phase structure to modulate ion transport and enable dendrite-free Li deposition. The PA-LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000 hours at an ultra-high current density of 20 mA cm−2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive-free electrolytes is achieved even after 500 cycles at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. 相似文献
6.
Tuoya Naren Gui-Chao Kuang Ruheng Jiang Piao Qing Hao Yang Jialin Lin Yuejiao Chen Weifeng Wei Xiaobo Ji Libao Chen 《Angewandte Chemie (International ed. in English)》2023,62(26):e202305287
Lithium (Li) metal anodes have the highest theoretical capacity and lowest electrochemical potential making them ideal for Li metal batteries (LMBs). However, Li dendrite formation on the anode impedes the proper discharge capacity and practical cycle life of LMBs, particularly in carbonate electrolytes. Herein, we developed a reactive alternative polymer named P(St-MaI) containing carboxylic acid and cyclic ether moieties which would in situ form artificial polymeric solid electrolyte interface (SEI) with Li. This SEI can accommodate volume changes and maintain good interfacial contact. The presence of carboxylic acid and cyclic ether pendant groups greatly contribute to the induction of uniform Li ion deposition. In addition, the presence of benzyl rings makes the polymer have a certain mechanical strength and plays a key role in inhibiting the growth of Li dendrites. As a result, the symmetric Li||Li cell with P(St-MaI)@Li layer can stably cycle for over 900 h under 1 mA cm−2 without polarization voltage increasing, while their Li||LiFePO4 full batteries maintain high capacity retention of 96 % after 930 cycles at 1C in carbonate electrolytes. The innovative strategy of artificial SEI is broadly applicable in designing new materials to inhibit Li dendrite growth on Li metal anodes. 相似文献
7.
Ran He Dr. Kuirong Deng Dr. Daize Mo Xiongcong Guan Dr. Yuanyuan Hu Prof. Kai Yang Prof. Zhenhua Yan Haijiao Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(7):e202317176
High-energy Li metal batteries (LMBs) consisting of Li metal anodes and high-voltage cathodes are promising candidates of the next generation energy-storage systems owing to their ultrahigh energy density. However, it is still challenging to develop high-voltage nonflammable electrolytes with superior anode and cathode compatibility for LMBs. Here, we propose an active diluent-anion synergy strategy to achieve outstanding compatibility with Li metal anodes and high-voltage cathodes by using 1,2-difluorobenzene (DFB) with high activity for yielding LiF as an active diluent to regulate nonflammable dimethylacetamide (DMAC)-based localized high concentration electrolyte (LHCE-DFB). DFB and bis(fluorosulfonyl)imide (FSI−) anion cooperate to construct robust LiF-rich solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI), which effectively stabilize DMAC from intrinsic reactions with Li metal anode and enhance the interfacial stability of the Li metal anodes and LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes. LHCE-DFB enables ultrahigh Coulombic efficiency (98.7 %), dendrite-free, extremely stable and long-term cycling of Li metal anodes in Li || Cu cells and Li || Li cells. The fabricated NCM811 || Li cells with LHCE-DFB display remarkably enhanced long-term cycling stability and excellent rate capability. This work provides a promising active diluent-anion synergy strategy for designing high-voltage electrolytes for high-energy batteries. 相似文献
8.
Li-Peng Hou Yuan Li Zheng Li Qian-Kui Zhang Dr. Bo-Quan Li Chen-Xi Bi Zi-Xian Chen Li-Ling Su Prof. Jia-Qi Huang Prof. Rui Wen Dr. Xue-Qiang Zhang Prof. Qiang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(32):e202305466
Practical lithium–sulfur (Li−S) batteries are severely plagued by the instability of solid electrolyte interphase (SEI) formed in routine ether electrolytes. Herein, an electrolyte with 1,3,5-trioxane (TO) and 1,2-dimethoxyethane (DME) as co-solvents is proposed to construct a high-mechanical-stability SEI by enriching organic components in Li−S batteries. The high-mechanical-stability SEI works compatibly in Li−S batteries. TO with high polymerization capability can preferentially decompose and form organic-rich SEI, strengthening mechanical stability of SEI, which mitigates crack and regeneration of SEI and reduces the consumption rate of active Li, Li polysulfides, and electrolytes. Meanwhile, DME ensures high specific capacity of S cathodes. Accordingly, the lifespan of Li−S batteries increases from 75 cycles in routine ether electrolyte to 216 cycles in TO-based electrolyte. Furthermore, a 417 Wh kg−1 Li−S pouch cell undergoes 20 cycles. This work provides an emerging electrolyte design for practical Li−S batteries. 相似文献
9.
Xiahui Zhang Panpan Dong Seunghyo Noh Xianghui Zhang Younghwan Cha Su Ha Ji-Hoon Jang Min-Kyu Song 《Angewandte Chemie (International ed. in English)》2023,62(4):e202212942
The LiOH-based cathode chemistry has demonstrated potential for high-energy Li−O2 batteries. However, the understanding of such complex chemistry remains incomplete. Herein, we use the combined experimental methods with ab initio calculations to study LiOH chemistry. We provide a unified reaction mechanism for LiOH formation during discharge via net 4 e− oxygen reduction, in which Li2O2 acts as intermediate in low water-content electrolyte but LiHO2 as intermediate in high water-content electrolyte. Besides, LiOH decomposes via 1 e− oxidation during charge, generating surface-reactive hydroxyl species that degrade organic electrolytes and generate protons. These protons lead to early removal of LiOH, followed by a new high-potential charge plateau (1 e− water oxidation). At following cycles, these accumulated protons lead to a new high-potential discharge plateau, corresponding to water formation. Our findings shed light on understanding of 4 e− cathode chemistries in metal–air batteries. 相似文献
10.
Kai Chen Gang Huang Jin-Ling Ma Jin Wang Dong-Yue Yang Xiao-Yang Yang Yue Yu Prof. Xin-Bo Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(38):16804-16810
The lithium (Li)–air battery has an ultrahigh theoretical specific energy, however, even in pure oxygen (O2), the vulnerability of conventional organic electrolytes and carbon cathodes towards reaction intermediates, especially O2−, and corrosive oxidation and crack/pulverization of Li metal anode lead to poor cycling stability of the Li-air battery. Even worse, the water and/or CO2 in air bring parasitic reactions and safety issues. Therefore, applying such systems in open-air environment is challenging. Herein, contrary to previous assertions, we have found that CO2 can improve the stability of both anode and electrolyte, and a high-performance rechargeable Li–O2/CO2 battery is developed. The CO2 not only facilitates the in situ formation of a passivated protective Li2CO3 film on the Li anode, but also restrains side reactions involving electrolyte and cathode by capturing O2−. Moreover, the Pd/CNT catalyst in the cathode can extend the battery lifespan by effectively tuning the product morphology and catalyzing the decomposition of Li2CO3. The Li–O2/CO2 battery achieves a full discharge capacity of 6628 mAh g−1 and a long life of 715 cycles, which is even better than those of pure Li–O2 batteries. 相似文献
11.
Dr. Yichao Cai Yunpeng Hou Dr. Yong Lu Dr. Qiu Zhang Dr. Zhenhua Yan Prof. Jun Chen 《Angewandte Chemie (International ed. in English)》2023,62(17):e202218014
Li−O2 batteries with bis(trifluoromethanesulfonyl)imide-based ionic liquid (TFSI-IL) electrolyte are promising because TFSI-IL can stabilize O2− to lower charge overpotential. However, slow Li+ transport in TFSI-IL electrolyte causes inferior Li deposition. Here we optimize weak solvating molecule (anisole) to generate anisole-doped ionic aggregate in TFSI-IL electrolyte. Such unique solvation environment can realize not only high Li+ transport parameters but also anion-derived solid electrolyte interface (SEI). Thus, fast Li+ transport is achieved in electrolyte bulk and SEI simultaneously, leading to robust Li deposition with high rate capability (3 mA cm−2) and long cycle life (2000 h at 0.2 mA cm−2). Moreover, Li−O2 batteries show good cycling stability (a small overpotential increase of 0.16 V after 120 cycles) and high rate capability (1 A g−1). This work provides an effective electrolyte design principle to realize stable Li deposition and high-performance Li−O2 batteries. 相似文献
12.
Yinping Qin Hefeng Wang Jingjing Zhou Ruyi Li Chun Jiang Yi Wan Xiaoyi Wang Zhenlian Chen Xiaolei Wang Yang Liu Bingkun Guo Deyu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(19):e202402456
The solid electrolyte interphase (SEI) membrane on the Li metal anode tends to breakdown and undergo reconstruction during operation, causing Li metal batteries to experience accelerated decay. Notably, an SEI membrane with self-healing characteristics can help considerably in stabilizing the Li-electrolyte interface; however, uniformly fixing the repairing agent onto the anode remains a challenging task. By leveraging the noteworthy film-forming attributes of bis(fluorosulfonyl)imide (FSI−) anions and the photopolymerization property of the vinyl group, the ionic liquid 1-vinyl-3-methylimidazolium bis(fluorosulfonyl)imide (VMI-FSI) was crosslinked with polyethylene oxide (PEO) in this study to form a self-healing film fixing FSI− groups as the repairing agent. When they encounter lithium metal, the FSI− groups are chemically decomposed into LiF & Li3N, which assist forming SEI membrane on lithium sheet and repairing SEI membrane in the cracks lacerated by lithium dendrite. Furthermore, the FSI− anions exchanged from film are electrochemically decomposed to generate inorganic salts to strengthen the SEI membrane. Benefiting from the self-healing behavior of the film, Li/LiCoO2 cells with the loading of 16.3 mg cm−2 exhibit the initial discharge capacities of 183.0 mAh ⋅ g−1 and are stably operated for 500 cycles with the retention rates of 81.4 % and the average coulombic efficiency of 99.97 %, operated between 3.0–4.5 V vs. Li+/Li. This study presents a new design approach for self-healing Li metal anodes and durable lithium metal battery. 相似文献
13.
Dr. Sailin Liu Dr. Jitraporn Vongsvivut Yanyan Wang Ruizhi Zhang Dr. Fuhua Yang Dr. Shilin Zhang Prof. Kenneth Davey Dr. Jianfeng Mao Prof. Zaiping Guo 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215600
Zinc metal battery (ZMB) is promising as the next generation of energy storage system, but challenges relating to dendrites and corrosion of the zinc anode are restricting its practical application. Here, to stabilize Zn anode, we report a controlled electrolytic method for a monolithic solid-electrolyte interphase (SEI) via a high dipole moment solvent dimethyl methylphosphonate (DMMP). The DMMP-based electrolytes can generate a homogeneous and robust phosphate SEI (Zn3(PO4)2 and ZnP2O6). Benefiting from the protecting impact of this in situ monolithic SEI, the zinc electrode exhibits long-term cycling of 4700 h and a high Coulombic efficiency 99.89 % in Zn|Zn and Zn|Cu cell, respectively. The full V2O5|Zn battery with DMMP-H2O hybrid electrolyte exhibits a high capacity retention of 82.2 % following 4000 cycles under 5 A g−1. The first success in constructing the monolithic phosphate SEI will open a new avenue in electrolyte design for highly reversible and stable Zn metal anodes. 相似文献
14.
Dr. Dechao Zhang Dr. Yuxuan Liu Zhaoyu Sun Dr. Zhengbo Liu Dr. Xijun Xu Lei Xi Prof. Shaomin Ji Prof. Min Zhu Prof. Jun Liu 《Angewandte Chemie (International ed. in English)》2023,62(44):e202310006
The deployment of lithium metal anode in solid-state batteries with polymer electrolytes has been recognized as a promising approach to achieving high-energy-density technologies. However, the practical application of the polymer electrolytes is currently constrained by various challenges, including low ionic conductivity, inadequate electrochemical window, and poor interface stability. To address these issues, a novel eutectic-based polymer electrolyte consisting of succinonitrile (SN) and poly (ethylene glycol) methyl ether acrylate (PEGMEA) is developed. The research results demonstrate that the interactions between SN and PEGMEA promote the dissociation of the lithium difluoro(oxalato) borate (LiDFOB) salt and increase the concentration of free Li+. The well-designed eutectic-based PAN1.2-SPE (PEGMEA: SN=1: 1.2 mass ratio) exhibits high ionic conductivity of 1.30 mS cm−1 at 30 °C and superior interface stability with Li anode. The Li/Li symmetric cell based on PAN1.2-SPE enables long-term plating/stripping at 0.3 and 0.5 mA cm−2, and the Li/LiFePO4 cell achieves superior long-term cycling stability (capacity retention of 80.3 % after 1500 cycles). Moreover, Li/LiFePO4 and Li/LiNi0.6Co0.2Mn0.2O2 pouch cells employing PAN1.2-SPE demonstrate excellent cycling and safety characteristics. This study presents a new pathway for designing high-performance polymer electrolytes and promotes the practical application of high-stable lithium metal batteries. 相似文献
15.
Siyuan Li Weidong Zhang Qiang Wu Lei Fan Xinyang Wang Xiao Wang Zeyu Shen Yi He Yingying Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15045-15051
A rechargeable Li metal anode coupled with a high-voltage cathode is a promising approach to high-energy-density batteries exceeding 300 Wh kg−1. Reported here is an advanced dual-additive electrolyte containing a unique solvation structure and it comprises a tris(pentafluorophenyl)borane additive and LiNO3 in a carbonate-based electrolyte. This system generates a robust outer Li2O solid electrolyte interface and F- and B-containing conformal cathode electrolyte interphase. The resulting stable ion transport kinetics enables excellent cycling of Li/LiNi0.8Mn0.1Co0.1O2 for 140 cycles with 80 % capacity retention under highly challenging conditions (≈295.1 Wh kg−1 at cell-level). The electrolyte also exhibits high cycling stability for a 4.6 V LiCoO2 (160 cycles with 89.8 % capacity retention) cathode and 4.95 V LiNi0.5Mn1.5O4 cathode. 相似文献
16.
Dr. Zhijie Wang Changsheng Chen Danni Wang Dr. Ye Zhu Dr. Biao Zhang 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303950
Ether electrolytes are promising for lithium metal batteries. Despite the intensive research in recent years, most state-of-the-art ether electrolytes still cannot form reliable electrode-electrolyte interfaces in NCM811-Li batteries at diluted concentrations, especially in those operating at elevated temperatures. We report a simple but effective strategy to break this bottleneck and stabilize interfaces in high-temperature NCM811-Li batteries in ether electrolytes. We propose that by gradually extending the terminal groups of glycol diethers from methyl groups to n-butyl groups, the comprehensive stability of ether electrolytes is improved. An anion-dominated solvation structure is realized at a concentration of 1 M. Accordingly, the electrode-electrolyte interactions are suppressed, and a thinner, denser, and more inorganic-rich solid- /cathode-electrolyte interface is achieved. Additionally, the surface phase transition and structural degradation of NCM811 cathode are alleviated. Consequently, in the ethylene glycol dibutyl ether-based electrolyte, the Coulombic efficiency for Li−Cu cells working at 60 °C is boosted to 99.41 % with a cycling life of over 200 cycles. The lifespan of high-temperature NCM811-Li cells is prolonged by more than 400 % with a stable average Coulombic efficiency of 99.77 % at quasi-practical conditions of 50 μm Li, lean electrolyte of 10 μL mAh−1, and medium-high cathode loading of >2.2 mAh cm−2. 相似文献
17.
《印度化学会志》2023,100(4):100959
The polymer-ceramic composite electrolytes have great application potential for next-generation solid state lithium batteries, as they have the merits to eliminate the problem of liquid organic electrolytes and enhancing chemical/electrochemical stability. However, polymer-ceramic composite electrolytes show poor ionic conductivity, which greatly hinders their practical applications. In this work, the addition of plasticizer ethylene carbonate (EC) into polymer-ceramic composite electrolyte for lithium batteries effectively promotes the ionic conductivity. A high ionic conductivity can be attained by adding 40 wt% EC to the polyethylene oxide (PEO)/polyvinylidene fluoride (PVDF)-Li7La3Zr2O12 (LLZO) based polymer-ceramic composite electrolytes, which is 2.64 × 10−4 S cm−1 (tested at room temperature). Furthermore, the cell assembled with lithium metal anode, this composite electrolyte, and LiFePO4 cathode can work more than 80 cycles at room temperature (tested at 0.2 C). The battery delivers a high reversible specific capacity after 89 cycles, which is 119 mAh g−1. 相似文献
18.
Zhihong Piao Hong-Rui Ren Gongxun Lu Kai Jia Junyang Tan Xinru Wu Zhaofeng Zhuang Zhiyuan Han Chuang Li Runhua Gao Xinyong Tao Guangmin Zhou Hui-Ming Cheng 《Angewandte Chemie (International ed. in English)》2023,62(15):e202300966
High-voltage lithium metal batteries (LMBs) pose severe challenges for the matching of electrolytes with aggressive electrodes, especially at low temperatures. Here, we report a rational modification of the Li+ solvation structure to extend the voltage and temperature operating ranges of conventional electrolytes. Ion-ion and ion-dipole interactions as well as the electrochemical window of solvents were tailored to improve oxidation stability and de-solvation kinetics of the electrolyte. Meanwhile, robust and elastic B and F-rich interphases are formed on both electrodes. Such optimization enables Li||LiNi0.5Mn1.5O4 cells (90.2 % retention after 400 cycles) and Li||LiNi0.6Co0.2Mn0.2O2 (NCM622) cells (74.0 % retention after 200 cycles) to cycle stably at an ultra-high voltage of 4.9 V. Moreover, NCM622 cells deliver a considerable capacity of 143.5 mAh g−1 at −20 °C, showing great potential for practical uses. The proposed strategy sheds light on further optimization for high-voltage LMBs. 相似文献
19.
Electron Delocalization Enables Sulfone-based Single-solvent Electrolyte for Lithium Metal Batteries
Muhammad Mominur Rahman Enyuan Hu 《Angewandte Chemie (International ed. in English)》2023,62(44):e202311051
Li-metal batteries (LMB), although providing high energy density, face the grand challenge of identifying good electrolyte solvents for cycling. Common solvents are either only stable against lithium metal anode or only stable against LiNixMnyCo1-x-yO2 (NMC) cathode. There is significant effort trying to increase the cathode stability for ether electrolytes, which are in general stable against lithium metal anode. In comparison, there is much less effort trying to increase the anode stability of electrolytes that are stable against NMC cathode. One example is the sulfone-based electrolyte. It has good cathode stability but is hindered from practical application because of (1) high viscosity and poor wetting capability and (2) poor anode stability. Here, we solve these issues by modifying the sulfone molecules using resonance and electron withdrawing effect. The viscosity is significantly reduced by delocalizing the electrons through introducing additional oxygen on the molecular backbone and applying appropriate fluorination. The resulting molecule 2,2,2-trifluoroethyl mesylate (TFEM) has decreased Lewis basicity and less reactivity toward Li+. The electrolyte based on TFEM as single solvent enables cycling of LMB under harsh conditions of low N/P ratio (21 mg/cm2 NMC811 and 50 μm Li) with 90 % capacity retention after 160 cycles at C/3 discharge rate. 相似文献
20.
Chen Zhao Dr. Gui-Liang Xu Dr. Tianshou Zhao Dr. Khalil Amine 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17787-17793
Electrolyte modulation simultaneously suppresses polysulfide the shuttle effect and lithium dendrite formation of lithium–sulfur (Li-S) batteries. However, the sluggish S redox kinetics, especially under high S loading and lean electrolyte operation, has been ignored, which dramatically limits the cycle life and energy density of practical Li-S pouch cells. Herein, we demonstrate that a rational combination of selenium doping, core–shell hollow host structure, and fluorinated ether electrolytes enables ultrastable Li stripping/plating and essentially no polysulfide shuttle as well as fast redox kinetics. Thus, high areal capacity (>4 mAh cm−2) with excellent cycle stability and Coulombic efficiency were both demonstrated in Li metal anode and thick S cathode (4.5 mg cm−2) with a low electrolyte/sulfur ratio (10 μL mg−1). This research further demonstrates a durable Li-Se/S pouch cell with high specific capacity, validating the potential practical applications. 相似文献