Recent progress in aging degradation of lithium-ion battery materials via in-situ optical microscopy
YAO Yiming,, LUAN Weiling,, CHEN Ying, SUN Min
CPCIF Key Laboratory of Power Battery Systems and Safety, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, China
Developing advanced lithium-ion batteries requires high-performance battery materials or optimized battery structures. An in-depth understanding of the aging degradation mechanism of battery materials is a prerequisite for improving battery performance. The in-situ optical microscopy method has advantages of convenient operation, a realistic simulation environment in in-situ reaction cells, and characterization from mesoscopic to macroscopic scales. This paper reviews the recent progress in the in-situ study of the aging degradation of lithium-ion battery materials via optical microscopy. Furthermore, typical structures of in-situ optical microscopy reaction cells are summarized. Then, several applications are reviewed, including lithium-ion concentration and its distribution, lithium plating, volume expansion and cracking of battery materials, and stress-strain evolution. Finally, future directions on optical microscope resolution, the functionality of in-situ reaction cells, the combined use of different characterization methods, and advanced image processing and analysis methods are proposed.
YAO Yiming. Recent progress in aging degradation of lithium-ion battery materials via in-situ optical microscopy[J]. Energy Storage Science and Technology, 2023, 12(3): 777-791
Fig. 2
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]
观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法。以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色。石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度。如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应。除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测。
Fig. 3
(a) Color change process of five graphite particles of different sizes and shapes at 0.1 C[33]; (b) color change of natural graphite single crystal flakes during the first lithium intercalation process[34]
除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素。复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径。反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35]。原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化。Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用。此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程。Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输。Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面。
Fig. 6
(a) Optical micrographs of lithium dendrite growth patterns throughout the charging cycle at three temperature conditions[45]; (b) voltage versus time at constant current applied at three temperature conditions[45]
Fig. 8
Morphological evolution of the i-Li island [52] (a) configuration of the optical cell with an i-Li island between the NMC and Li electrodes; (b) Li islands in the initial state (t=0 h) and intermediate states (t=3 h) during the charging phase h) optical microscope images; (c) optical microscope images of Li islands in the initial state (t=0 h) and intermediate state (t=3 h) during the discharge
Fig. 9
The morphological evolution process of graphite anode surface and the corresponding external characteristic curves[22] (a) voltage curves of graphite during a 10 min OCV rest period for two cells; (b) local optical images of the graphite surfaces at different points in time during the OCV rest; (c) dV/dt curves associated with the two voltage profiles; (d) blue of graphite during the extended 50 min OCV rest period
Fig. 12
The thickness variation of the NCM and graphite electrode[71] (a) optical microscope cross-sectional images of the electrode; (b) evolution of the volume expansion rate
Fig. 14
Evolution of strain field on graphite anode surface with lithium concentration changing[83] (a) evolution of the strain field on the surface of the graphite anode; (b) average concentration and average in-plane strain as a function of time on the surface of the graphite anode, respectively
MIAO P, YAO Z, JOHN L, et al. Current situations and prospects of energy storage batteries[J]. Energy Storage Science and Technology, 2020, 9(3): 670-678.
LIU D Q, SHADIKE Z, LIN R Q, et al. Review of recent development of in situ/operando characterization techniques for lithium battery research[J]. Advanced Materials, 2019, 31(28): doi: 10.1002/adma.201806620.
WALDMANN T, ITURRONDOBEITIA A, KASPER M, et al. Review—post-mortem analysis of aged lithium-ion batteries: Disassembly methodology and physico-chemical analysis techniques[J]. Journal of the Electrochemical Society, 2016, 163(10): doi: 10.1149/2.1211609jes.
KE C Z, XIAO B S, LI M, et al. Research progress in understanding of lithium storage behavior and reaction mechanism of electrode materials through in situ transmission electron microscopy[J]. Energy Storage Science and Technology, 2021, 10(4): 1219-1236.
LI W J, ZHENG J Y, GU L, et al. Researches on In-situ and ex-situ characterization techniques in lithium batteries[J]. Journal of Electrochemistry, 2015, 21(2): 99-114.
WANG X, ZHOU H, CHEN Z H, et al. Synchrotron-based X-ray diffraction and absorption spectroscopy studies on layered LiNixMnyCozO2 cathode materials: A review[J]. Energy Storage Materials, 2022, 49: 181-208.
TAO S W, LI M, LYU M Q, et al. In operando closed-cell transmission electron microscopy for rechargeable battery characterization: Scientific breakthroughs and practical limitations[J]. Nano Energy, 2022, 96: doi: 10.1016/j.nanoen.2022.107083.
YU C M, LI L, CAI Y C. The application of scanning electron microscopy in the field of battery materials[J]. Journal of Chinese Electron Microscopy Society, 2021, 40(3): 339-347.
NEUPANE S, VALENCIA-RAMÍREZ A, LOSADA-PÉREZ P, et al. In operando atomic force microscopy imaging of electrochemical interfaces: A short perspective[J]. Physica Status Solidi (a), 2021, 218(24): doi: 10.1002/pssa.202100470.
SWALLOW J G, WOODFORD W H, MCGROGAN F P, et al. Effect of electrochemical charging on elastoplastic properties and fracture toughness of LixCoO2[J]. Journal of the Electrochemical Society, 2014, 161(11): doi: 10.1149/2.0141411jes.
STIASZNY B, ZIEGLER J C, KRAUß E E, et al. Electrochemical characterization and post-mortem analysis of aged LiMn2O4-Li(Ni0.5Mn0.3Co0.2)O2/graphite lithium ion batteries. Part I: Cycle aging[J]. Journal of Power Sources, 2014, 251: 439-450.
CHEN Y X, TORRES-CASTRO L, CHEN K H, et al. Operando detection of Li plating during fast charging of Li-ion batteries using incremental capacity analysis[J]. Journal of Power Sources, 2022, 539: doi: 10.1016/j.jpowsour.2022.231601.
HAFNER C, BERNTHALER T, KNOBLAUCH V, et al. The materialographic preparation and microstructure characterization of lithium ion accumulators[J]. Practical Metallography, 2012, 49: 75-85.
CONDER J, MARINO C, NOVáK P, et al. Do imaging techniques add real value to the development of better post-Li-ion batteries?[J]. Journal of Materials Chemistry A, 2018, 6(8): 3304-3327.
SUN Y M, SEH Z W, LI W Y, et al. In-operando optical imaging of temporal and spatial distribution of polysulfides in lithium-sulfur batteries[J]. Nano Energy, 2015, 11: 579-586.
BAI P, LI J, BRUSHETT F R, et al. Transition of lithium growth mechanisms in liquid electrolytes[J]. Energy & Environmental Science, 2016, 9(10): 3221-3229.
THOMAS-ALYEA K E, JUNG C, SMITH R B, et al. In situ observation and mathematical modeling of lithium distribution within graphite[J]. Journal of the Electrochemical Society, 2017, 164(11): doi: 10.1149/2.0061711jes.
OTOYAMA M, SAKUDA A, HAYASHI A, et al. Optical microscopic observation of graphite composite negative electrodes in all-solid-state lithium batteries[J]. Solid State Ionics, 2018, 323: 123-129.
ARISE I, MIYAHARA Y, MIYAZAKI K, et al. Functional role of aramid coated separator for dendrite suppression in lithium-ion batteries[J]. Journal of the Electrochemical Society, 2022, 169(1): doi: 10.1149/1945-7111/ac4b1e.
CHEN Y X, CHEN K H, SANCHEZ A J, et al. Operando video microscopy of Li plating and re-intercalation on graphite anodes during fast charging[J]. Journal of Materials Chemistry A, 2021, 9(41): 23522-23536.
SANCHEZ A J, KAZYAK E, CHEN Y X, et al. Plan-view Operando video microscopy of Li metal anodes: Identifying the coupled relationships among nucleation, morphology, and reversibility[J]. ACS Energy Letters, 2020, 5(3): 994-1004.
OTOYAMA M, KOWADA H, SAKUDA A, et al. Operando confocal microscopy for dynamic changes of Li+ ion conduction path in graphite electrode layers of all-solid-state batteries[J]. The Journal of Physical Chemistry Letters, 2020, 11(3): 900-904.
LYU S Q, LI N, CHEN H S, et al. Progresses in visualization and quantitative analysis of the electrode process in rechargeable batteries[J]. Energy Storage Science and Technology, 2022, 11(3): 795-817.
ARAI H, YAGUCHI A, NISHIMURA Y, et al. Operando optical analysis of LiFePO4 composite electrodes[J]. The Journal of Physical Chemistry C, 2021, 125(7): 3776-3780.
AZHAGURAJAN M, NAKATA A, ARAI H, et al. Effect of vanillin to prevent the dendrite growth of Zn in zinc-based secondary batteries[J]. Journal of the Electrochemical Society, 2017, 164(12): doi: 10.1149/2.0221712jes.
FENG Y, NGO T D T, PANAGOPOULOU M, et al. Lithiation of pure and methylated amorphous silicon: Monitoring by operando optical microscopy and ex situ atomic force microscopy[J]. Electrochimica Acta, 2019, 302: 249-258.
WAN J Y, BAO W Z, LIU Y, et al. In situ investigations of Li-MoS2 with planar batteries[J]. Advanced Energy Materials, 2015, 5(5): doi: 10.1002/aenm.201401742.
ZHANG Y W, FINCHER C, MCPROUTY S, et al. In-operando imaging of polysulfide catholytes for Li-S batteries and implications for kinetics and mechanical stability[J]. Journal of Power Sources, 2019, 434: doi: 10.1016/j.jpowsour.2019.226727.
SONG Y X, SHI Y, WAN J, et al. Direct tracking of the polysulfide shuttling and interfacial evolution in all-solid-state lithium-sulfur batteries: A degradation mechanism study[J]. Energy & Environmental Science, 2019, 12(8): 2496-2506.
AGRAWAL S, BAI P. Dynamic interplay between phase transformation instabilities and reaction heterogeneities in particulate intercalation electrodes[J]. Cell Reports Physical Science, 2022, 3(5): doi: 10.1016/j.xcrp.2022.100854.
LODICO J J, LAI C H, WOODALL M, et al. Irreversibility at macromolecular scales in the flake graphite of the lithium-ion battery anode[J]. Journal of Power Sources, 2019, 436: doi: 10.1016/j.jpowsour.2019.226841.
MENG D C, MA Z F, LI L S. Mesoscale reaction heterogeneities in lithium-ion batteries[J]. Chemical Industry and Engineering Progress, 2021, 40(9): 4869-4881.
YANG L, CHEN H S, SONG W L, et al. Effect of defects on diffusion behaviors of lithium-ion battery electrodes: in situ optical observation and simulation[J]. ACS Applied Materials & Interfaces, 2018, 10(50): 43623-43630.
SHI B Q, HAN B, XIE H M, et al. C-rate related diffusion process of the graphite electrode by in situ experiment and analysis[J]. Electrochimica Acta, 2021, 378: doi: 10.1016/j.electacta.2021.138151.
FUKUMITSU H, OMORI M, TERADA K, et al. Development of in situ cross-sectional Raman imaging of LiCoO2 cathode for Li-ion battery[J]. Electrochemistry, 2015, 83(11): 993-996.
HAN X B, LU L G, ZHENG Y J, et al. A review on the key issues of the lithium ion battery degradation among the whole life cycle[J]. eTransportation, 2019, 1: doi: 10.1016/j.etran.2019.100005.
LI Z, HUANG J, YANN LIAW B, et al. A review of lithium deposition in lithium-ion and lithium metal secondary batteries[J]. Journal of Power Sources, 2014, 254: 168-182.
REN D S, FENG X N, HAN X B, et al. Recent progress on evolution of safety performance of lithium-ion battery during aging process[J]. Energy Storage Science and Technology, 2018, 7(6): 957-966.
EDGE J S, O'KANE S, PROSSER R, et al. Lithium ion battery degradation: What You need to know[J]. Physical Chemistry Chemical Physics: PCCP, 2021, 23(14): 8200-8221.
REN D S, HSU H, LI R H, et al. A comparative investigation of aging effects on thermal runaway behavior of lithium-ion batteries[J]. eTransportation, 2019, 2: doi: 10.1016/j.etran.2019.100034.
FEAR C, ADHIKARY T, CARTER R, et al. In operando detection of the onset and mapping of lithium plating regimes during fast charging of lithium-ion batteries[J]. ACS Applied Materials & Interfaces, 2020, 12(27): 30438-30448.
LOVE C T, BATURINA O A, SWIDER-LYONS K E. Observation of lithium dendrites at ambient temperature and below[J]. ECS Electrochemistry Letters, 2015, 4(2): doi: 10.1149/2.0041502eel.
KÜHNLE H, KNOBBE E, FIGGEMEIER E. In situ optical investigations of lithium depositions on pristine and aged lithium metal electrodes[J]. Journal of the Electrochemical Society, 2021, 168(2): doi: 10.1149/1945-7111/abdeeb.
SHI Y, WAN J, LIU G X, et al. Interfacial evolution of lithium dendrites and their solid electrolyte interphase shells of quasi-solid-state lithium-metal batteries[J]. Angewandte Chemie (International Ed in English), 2020, 59(41): 18120-18125.
REN D S, SMITH K, GUO D X, et al. Investigation of lithium plating-stripping process in Li-ion batteries at low temperature using an electrochemical model[J]. Journal of the Electrochemical Society, 2018, 165(10): doi: 10.1149/2.0661810jes.
WALDMANN T, HOGG B I, WOHLFAHRT-MEHRENS M. Li plating as unwanted side reaction in commercial Li-ion cells-A review[J]. Journal of Power Sources, 2018, 384: 107-124.
SANCHEZ A J, KAZYAK E, CHEN Y X, et al. Lithium stripping: Anisotropic evolution and faceting of pits revealed by operando 3-D microscopy[J]. Journal of Materials Chemistry A, 2021, 9(37): 21013-21023.
ZHOU Y, DENG Z, HUANG Z Y, et al. Research progress on detection methods for lithium plating in anode of lithium-ion batteries[J]. Journal of the Chinese Ceramic Society, 2022, 50(1): 84-100.
HE X, SCHMOHL S, WIEMHÖFER H D. Direct observation and suppression effect of lithium dendrite growth for polyphosphazene based polymer electrolytes in lithium metal cells[J]. ChemElectroChem, 2019, 6(4): 1166-1176.
LI W Y, YAO H B, YAN K, et al. The synergetic effect of lithium polysulfide and lithium nitrate to prevent lithium dendrite growth[J]. Nature Communications, 2015, 6: doi: 10.1038/ncomms8436.
RODRIGUEZ R, LOEFFLER K E, EDISON R A, et al. Effect of the electrolyte on the cycling efficiency of lithium-limited cells and their morphology studied through in situ optical imaging[J]. ACS Applied Energy Materials, 2018, 1(11): 5830-5835.
WAN G J, GUO F H, LI H, et al. Suppression of dendritic lithium growth by in situ formation of a chemically stable and mechanically strong solid electrolyte interphase[J]. ACS Applied Materials & Interfaces, 2018, 10(1): 593-601.
HAN B, FENG D Y, LI S, et al. Self-regulated phenomenon of inorganic artificial solid electrolyte interphase for lithium metal batteries[J]. Nano Letters, 2020, 20(5): 4029-4037.
LI Q, QUAN B G, LI W J, et al. Electro-plating and stripping behavior on lithium metal electrode with ordered three-dimensional structure[J]. Nano Energy, 2018, 45: 463-470.
YU C, DU Y, HE R H, et al. Hollow SiOx/C microspheres with semigraphitic carbon coating as the "lithium host" for dendrite-free lithium metal anodes[J]. ACS Applied Energy Materials, 2021, 4(4): 3905-3912.
GUAN R Z, LIU S, WANG C, et al. Lithiophilic Sn sites on 3D Cu current collector induced uniform lithium plating/stripping[J]. Chemical Engineering Journal, 2021, 425: doi: 10.1016/j.cej.2021.130177.
YANG J, FENG T T, ZHI C, et al. Bimetallic composite induced ultra-stable solid electrolyte interphase for dendrite-free lithium metal anode[J]. Journal of Colloid and Interface Science, 2021, 599: 819-827.
DE VASCONCELOS L S, XU R, XU Z R, et al. Chemomechanics of rechargeable batteries: Status, theories, and perspectives[J]. Chemical Reviews, 2022, 122(15): 13043-13107.
KONDRAKOV A O, SCHMIDT A, XU J, et al. Anisotropic lattice strain and mechanical degradation of high- and low-nickel NCM cathode materials for Li-ion batteries[J]. The Journal of Physical Chemistry C, 2017, 121(6): 3286-3294.
OBROVAC M N, CHRISTENSEN L. Structural changes in silicon anodes during lithium insertion/extraction[J]. Electrochemical and Solid-State Letters, 2004, 7(5): doi: 10.1149/1.1652421.
TIMMONS A, DAHN J R. Isotropic volume expansion of particles of amorphous metallic alloys in composite negative electrodes for Li-ion batteries[J]. Journal of the Electrochemical Society, 2007, 154(5): doi: 10.1149/1.2711075.
DOKKO K. In situ observation of LiNiO2 single-particle fracture during Li-ion extraction and insertion[J]. Electrochemical and Solid-State Letters, 1999, 3(3): 125.
CHEN Y, LUAN W L, CHEN H F, et al. Multi-scale failure behavior of cathode in lithium-ion batteries based on stress field[J]. Journal of Inorganic Materials, 2022, 37(8): 918-923.
WANG Y N, LI H, WANG Z K, et al. Progress on failure mechanism of lithium ion battery caused by diffusion induced stress[J]. Journal of Inorganic Materials, 2020, 35(10): 1071-1087.
WALDMANN T, MOLINERO M B, WILDNER L, et al. Cross-sectional in situ optical microscopy with simultaneous electrochemical measurements for lithium-ion full cells[J]. Journal of the Electrochemical Society, 2022, 169(5): doi: 10.1149/1945-7111/ac6c57.
GAO J H, CHEN Y L, MENG F H, et al. Research on in situ optical microscopic observation in lithium-ion batteries[J]. Energy Storage Science and Technology, 2022, 11(1): 53-59.
YOON D H, MARINARO M, AXMANN P, et al. Study of the binder influence on expansion/contraction behavior of silicon alloy negative electrodes for lithium-ion batteries[J]. Journal of the Electrochemical Society, 2020, 167(16): doi: 10.1149/1945-7111/abcf4f.
HERNANDEZ C R, ETIEMBLE A, DOUILLARD T, et al. A facile and very effective method to enhance the mechanical strength and the cyclability of Si-based electrodes for Li-ion batteries[J]. Advanced Energy Materials, 2018, 8(6): doi: 10.1002/aenm. 201701787.
CHEN Y, CHEN H F, LUAN W L. Shakedown, ratcheting and fatigue analysis of cathode coating in lithium-ion battery under steady charging-discharging process[J]. Journal of the Mechanics and Physics of Solids, 2021, 150: doi: 10.1016/j.jmps.2021.104366.
FENG X L, YANG L, ZHANG M L, et al. Failure mechanics inner lithium ion batteries: In-situ multi-field experimental methods[J]. Energy Storage Science and Technology, 2019, 8(6): 1062-1075.
JANGID M K, MUKHOPADHYAY A. Real-time monitoring of stress development during electrochemical cycling of electrode materials for Li-ion batteries: Overview and perspectives[J]. Journal of Materials Chemistry A, 2019, 7(41): 23679-23726.
QI Z F, SHAN Z Q, MA W H, et al. Strain analysis on electrochemical failures of nanoscale silicon electrode based on three-dimensional in situ measurement[J]. Applied Sciences, 2020, 10(2): doi: 10.3390/app10020468.
QI Y, HARRIS S J. In situ observation of strains during lithiation of a graphite electrode[J]. Journal of the Electrochemical Society, 2010, 157(6): doi: 10.1149/1.3377130.
XU Z Y, SHI X L, ZHUANG X Q, et al. Chemical strain of graphite-based anode during lithiation and delithiation at various temperatures[J]. Research (Washington, D C), 2021, 2021: doi: 10.34133/2021/9842391.
XIE H M, YANG W, KANG Y L, et al. In-situ strain field measurement and mechano-electro-chemical analysis of graphite electrodes via fluorescence digital image correlation[J]. Experimental Mechanics, 2021, 61(8): 1249-1260.
AHMED R A, EBECHIDI N, REISYA I, et al. Pressure-induced interfacial contacts and the deformation in all solid-state Li-ion batteries[J]. Journal of Power Sources, 2022, 521: doi: 10.1016/j.jpowsour.2021.230939.
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
... [22](a) 两个电池在10 min静止期间的石墨电压曲线;(b) 在静止期间不同时间点的石墨表面的局部光学图像;(c) 与两个开路电压曲线相关的dV/dt 曲线;(d) 在延长至50 min静置期间,石墨表面蓝色的百分比The morphological evolution process of graphite anode surface and the corresponding external characteristic curves[22] (a) voltage curves of graphite during a 10 min OCV rest period for two cells; (b) local optical images of the graphite surfaces at different points in time during the OCV rest; (c) dV/dt curves associated with the two voltage profiles; (d) blue of graphite during the extended 50 min OCV rest periodFig. 9
... [22] (a) voltage curves of graphite during a 10 min OCV rest period for two cells; (b) local optical images of the graphite surfaces at different points in time during the OCV rest; (c) dV/dt curves associated with the two voltage profiles; (d) blue of graphite during the extended 50 min OCV rest periodFig. 9
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
... 除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
Typical voltage curves of intercalated lithium stages of graphite materials and the color change process of graphite particles at different lithium concentrations[26]Fig. 22 原位光学显微镜在锂离子电池老化衰减研究中的应用2.1 锂离子浓度及其分布
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
1
... 观测充放电过程中活性材料中的锂浓度通常采用原位光学显微镜结合色度法.以石墨为例,随着锂离子的嵌入和脱出,石墨颗粒相变为锂石墨插层化合物Li x C6,并根据不同的相呈现出不同的颜色.石墨颗粒颜色、锂浓度和Li x C6相存在对应关系,可以根据颜色变化推断石墨颗粒中的锂浓度.如图2所示,Gao等[26]展示了高定向热解石墨在嵌锂过程中四个阶段的颜色变化过程,1L阶段石墨呈灰色,此时石墨刚开始嵌入锂离子,锂浓度小于0.05;3L阶段的LiC18为蓝色,对应的锂浓度大致为0.22;2阶段的LiC12为红色,对应的锂浓度大致为0.5;最后是1阶段金色的完全锂化石墨LiC6,对应的锂浓度为1,该变化过程也与石墨嵌锂的典型电压曲线相对应.除了石墨以外,色度法同样可以用于追踪其他活性材料在电池工作期间的锂离子脱嵌状态,如磷酸铁锂[27]、锌金属[28]、多晶硅[29]以及硫化钼[30],也可以应用于固态电解质[31-32]的观测. ...
... [33];(b) 天然石墨单晶薄片在第一次嵌锂过程中的颜色变化过程[34](a) Color change process of five graphite particles of different sizes and shapes at 0.1 C[33]; (b) color change of natural graphite single crystal flakes during the first lithium intercalation process[34]Fig. 3
除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
... [33]; (b) color change of natural graphite single crystal flakes during the first lithium intercalation process[34]Fig. 3
除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
... [34](a) Color change process of five graphite particles of different sizes and shapes at 0.1 C[33]; (b) color change of natural graphite single crystal flakes during the first lithium intercalation process[34]Fig. 3
除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
... [34]Fig. 3
除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
1
... 除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
1
... 除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
3
... 除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
... [36]Lithium ion transport process of commercial graphite electrodes with prefabricated defects during charging[36]Fig. 4
... 除了锂离子在活性材料的固相扩散速率之外,复合电极结构也是影响锂离子传输过程的重要影响因素.复合电极由活性材料、导电材料和黏结剂组成,为脱嵌锂离子的电化学反应提供了离子和电子的传输路径.反应的不均匀性,特别是沿电极厚度方向离子和电子传输的不平衡,限制了电池的性能[35].原位光学显微镜方法具有良好的时间分辨率和空间分辨率,可以追踪电池运行过程中电极的动态变化.Yang等[36]在商用石墨电极上预制了不同类型的缺陷以探究缺陷周围锂离子传输过程,如图4所示,发现垂直于锂离子传输方向的填充缺陷对锂离子传输有明显的抑制作用,而平行于锂离子传输方向的填充缺陷对锂离子传输有明显的促进作用.此外,填充缺陷的介质,如气泡或电解液,也会影响锂离子传输过程.Otoyama等[24]观测了全固态锂电池的石墨复合电极中离子传输路径的动态变化,发现循环过程中复合电极形成了孔隙和裂纹并限制了锂离子在厚度方向的传输.Shi等[37]探究了高充放电倍率下锂离子在石墨负极的扩散过程,发现高充放电倍率加速了Li x C6的演化过程,缩短了相变的持续时间,导致电极处于多相共存状态,因此出现明显不同相的分界面. ...
... [45];(b) 三种温度条件下施加的恒定电流下的电压与时间的关系[45](a) Optical micrographs of lithium dendrite growth patterns throughout the charging cycle at three temperature conditions[45]; (b) voltage versus time at constant current applied at three temperature conditions[45]Fig. 6
... [45](a) Optical micrographs of lithium dendrite growth patterns throughout the charging cycle at three temperature conditions[45]; (b) voltage versus time at constant current applied at three temperature conditions[45]Fig. 6
... [52](a) NMC和Li电极之间布置锂岛的示意图;(b) 充电阶段Li岛在初始状态(t=0 h)和中间状态(t=3 h)的光学显微镜图像;(c) 放电阶段Li岛在初始状态(t=0 h)和中间状态(t=3 h)的光学显微镜图像Morphological evolution of the i-Li island [52] (a) configuration of the optical cell with an i-Li island between the NMC and Li electrodes; (b) Li islands in the initial state (t=0 h) and intermediate states (t=3 h) during the charging phase h) optical microscope images; (c) optical microscope images of Li islands in the initial state (t=0 h) and intermediate state (t=3 h) during the dischargeFig. 8
... [52] (a) configuration of the optical cell with an i-Li island between the NMC and Li electrodes; (b) Li islands in the initial state (t=0 h) and intermediate states (t=3 h) during the charging phase h) optical microscope images; (c) optical microscope images of Li islands in the initial state (t=0 h) and intermediate state (t=3 h) during the dischargeFig. 8
... [55](a) Li2S8 和LiNO3;(b) LiNO3Effect of electrolyte additives on the growth of lithium dendrites on lithium metal surfaces[55] (a) Li2S8 and LiNO3; (b) only LiNO3Fig. 102.3 电池材料体积膨胀及开裂
... [67](a) a-Si0.57Al0.28Fe0.15;(b) a-Si0.64Sn0.36Volume changes of the two negative active particles during charging and discharging[67] (a) a-Si0.57Al0.28Fe0.15; (b) a-Si0.64Sn0.36Fig. 11
... [71](a) 极片光学显微镜横截面图像;(b) 体积膨胀率的演化The thickness variation of the NCM and graphite electrode[71] (a) optical microscope cross-sectional images of the electrode; (b) evolution of the volume expansion rateFig. 12
... [83](a) 石墨负极表面应变场演化过程;(b) 石墨负极表面平均锂浓度和平均应变曲线各自时间的关系Evolution of strain field on graphite anode surface with lithium concentration changing[83] (a) evolution of the strain field on the surface of the graphite anode; (b) average concentration and average in-plane strain as a function of time on the surface of the graphite anode, respectivelyFig. 14
... [83] (a) evolution of the strain field on the surface of the graphite anode; (b) average concentration and average in-plane strain as a function of time on the surface of the graphite anode, respectivelyFig. 14