Table 1

Comparison of melting point, boiling point and flash point of carbonate and ether electrolyte solvents commonly used in lithium batteries 29."

Fig 1

(a) Schematic diagram of abuse conditions related to thermal runaway of lithium ion battery; (b) three levels of internal short circuit 20. Adapted from Elsevier publisher."

Fig 2

(a) The general characteristics of thermal runaway of lithium ion batteries 19; (b) DSC heating curve of lithium metal and sulfur 40; (c) DSC curve of lithium metal in 1 mol·L-1 LiPF6/(EC + DEC) electrolyte 40; (d) ARC test curve of lithium metal and four ISEs and schematic diagram of the cause of thermal runaway 38. (a, d) Adapted from Elsevier publisher. (b, c) Adapted from IOP publisher "

Fig 3

(a) SEM images of the morphological evolution of lithium dendrites in lithium-lithium symmetric batteries under different current densities 43; (b) SEM images of the lithium layer under different current densities and temperatures 49; (c) schematic diagram of the principle of lithium nucleation and deposition processes at high and low temperatures 49; (d) cryo-EM shows the difference in SEI nanostructures formed at low and high temperatures 50; (e) three basic processes in the process of lithium ion electrodeposition Schematic diagram 53. (a) Adapted from The American Association for the Advancement of Science publisher. (b, c) Adapted with permission from copyright 2019, John Wiley and Sons publisher. (d) Adapted from Springer Nature publisher. (e) Adapted with permission from copyright 2020, American Chemical Society."

Fig 4

(a) Comparison of the burning phenomenon of EC + DMC solvent (left) and TEP + FEC (right) with an external fire (Ⅰ) or without external fire (Ⅱ) 56; (b) 25 and 60 ℃ cross-section and top SEM image of the lithium deposition layer after the next 50 cycles 47; (c) comparison of battery cycle efficiency and stability using conventional electrolyte, HCE and LHCE 58. (a) Adapted with permission from copyright 2018, Royal Society of Chemistry publisher. (b) Adapted with permission from copyright 2018, John Wiley and Sons publisher. (c) Adapted from Elsevier publisher."

Fig 5

(a) Comparison of battery cycle performance and coulombic efficiency with different amounts of IL addition 61; (b) comparison of wettability and contact angle of separator with DIL (diluted ionic liquid), CIL (highly concentrated ionic liquid) and LCIL 62; (c) top and cross-sectional SEM images of SEI formed in DIL, CIL and LCIL 62. (a) Adapted with permission from copyright 2013, Royal Society of Chemistry publisher. (b) Adapted with permission from copyright 2020, John Wiley and Sons publisher. (c) Adapted with permission from copyright 2020, John Wiley and Sons publisher."

Fig 6

(a) Common substances in electrolytes and diagrams of lithium ion solvation structure in dilute ether, concentrated ether, and concentrated siloxane electrolytes 64; (b) different electrolytes after 100 cycles (the solvents in Ⅰ, Ⅱ, and Ⅲ are respectively EC/DMC, DMC/FEC and FEC/FEMC/HFE) SEM images of lithium metal morphology 65; (c) schematic diagram of super electrolyte using non-polar solvent 66. (a) Adapted with permission from copyright 2020, John Wiley and Sons publisher. (b) Adapted from Springer Nature publisher. (c) Adapted from Springer Nature publisher."

Fig 7

(a) Bare PE separator (the first three from top to bottom) and PDA coating (fourth)) digital camera images of PE separator under different RF sputtering power and time 72; (b) schematic diagram of egg and eggshell structure and RESM preparation process 73; (c) schematic diagram of phase inversion method mechanism and overall process of material preparation 74. (a) Adapted with permission from copyright 2015, RSC Publishing publisher. (b, c) Adapted from Elsevier publisher."

Fig 8

(a) Comparison of thermal shrinkage behavior of two kinds of membranes exposed to different temperatures for 0.5 h 77; (b) schematic diagram of CPC membrane production process 79; (c) original state of CPC membrane comparison with SEM which has a thermal shutdown effect at 200 ℃ 79. (a) Adapted from Elsevier publisher. (b, c) Adapted with permission from copyright 2018, John Wiley and Sons publisher."

Fig 9

(a) Comparison of the burning time of liquid electrolyte in FRS and PE/PP separators 28; (b) schematic diagram of the principle of the flame retardant separator with a core-shell structure 82. (a) Adapted from Elsevier publisher. (b) Adapted from American Association for the Advancement of Science publisher."

Fig 10

(a) Schematic diagram of the design and manufacturing principle of smart batteries 83; (b) SiO2 sandwich separator to eliminate lithium dendrites Schematic diagram 85; (c) schematic diagram of the principle of the smart separator changing the growth direction of lithium dendrites 86. (a, c) Adapted from Springer Nature publisher. (b) Adapted with permission from copyright 2016, John Wiley and Sons publisher."

Fig 11

(a) Schematic diagram of thermally responsive polymer inhibiting ion conduction; (b) schematic diagram of the composition of TSPE (PDOL and PLAS); (c) digital photo of the obtained TSPE film 92. Adapted with permission from copyright 2019, American Chemical Society."