Fig 1

High resolution SSNMR on battery materials. (a) 7Li MAS-NMR spectrum of pristine Li-rich Li1.2Ni0.13Mn0.54Co0.13O2 (LNMCO) with fine structure information for Li at transition metal (LiTM)and Li (LiLi) layers, respectively 4. (b) The obtained pjMATPASS spectra for Li2MnO3, a pure isotropic spectrum is shown as sum projection on the right 4. (c) Li+ pathway determination in composite electrolyte: 6Li replace 7Li on its way under potential stimulation 30 (a, b) Reprinted with permission from Ref. 4, Copyright (2017) American Chemical Society. (c) Reprinted with permission from Ref. 30, Copyright (2016) Wiley."

Fig 2

NMR adapted cell design. (a) Teflon 2032-size coin cell for in situ NMR 53. (b) Bellcore-type of bag cell for in situ NMR study 56. (c) Different versions of plastic cylindrical cells for in situ NMR investigation 28, 49, 57, 64, 69 (a) Adapted Ref. 53 from Elsevier publisher. (b) Adapted Ref. 56 from Elsevier publisher. (c) Adapted from Ref. 57 published by Elsevier. Reprinted with permission from Ref. 64, Copyright (2013) Springer Nature. Reprinted with permission from Ref. 28, Copyright (2014) American Chemical Society. Reprinted with permission from Ref. 49, Copyright (2015) American Chemical Society. Reprinted with permission from Ref. 69, Copyright (2018) Royal Society of Chemistry."

Fig 3

In situ NMR on batteries. (a) 31P NMR for Cu3P/Li half-cell investigation 57. Cycling curve is presented to the left and the vertical axis to the right demonstrates the molar fraction of Li ions. (b) 31P study a Ni5P4/Li half-cell 7. (c) 7Li NMR on a Li-Si battery for cycling mechanism and cause of self-discharge 71. Charge-discharge curves with specific capacity are shown to the right. (d) 23Na determination of the formation of Na dendrite 72 (a) Adapted from Ref. 57 published by Elsevier. (b) Reprinted with permission from Ref. 7, Copyright (2013) Royal Society of Chemistry. (c) Reprinted with permission from Ref. 71, Copyright (2009) American Chemical Society. (d) Reprinted with permission from Ref. 72, Copyright (2016) American Chemical Society. "

Fig 4

In situ MRI for Li ion batteries. (a) Coin type cell 7Li NMR images of the counter electrode and the lithium dendrites that were formed on a hard carbon electrode before (left) and after (right) passing current through the cell 53. (b) 7Li chemical shift imaging (CSI) for a Li/Li symmetric cell before and after polarization 48. (c) 7Li S-ISIS image with both position and chemical shift information that cannot be obtained by using CSI technique as shown in (d) 50 (a) Adapted from Ref. 53 published by Elsevier. (b) Reprinted with permission from Ref. 48, Copyright (2012) Springer Nature. (c) Reprinted with permission from Ref. 50, Copyright (2016) Springer Nature. "

Fig 9

Magnetic susceptibility for electrodes at different orientations. (a) 7Li NMR spectra 91 and (b) 7Li MRI 18 for Li metal. (c) 7Li NMR spectra for Li-rich Li1.08Mn1.92O4 electrode film 59 (a) Reprinted with permission from Ref. 91, Copyright (2013) American Chemical Society. (b) Adapted from Ref. 18 published by Elsevier. (c) Adapted from Ref. 59 published by Elsevier. "

Scheme 1

(a) Conventional pulse for chemical shift imaging (CSI); (b) Scanning image-selected in situ spectroscopy (S-ISIS) pulse sequence 50"

Fig 5

In situ MRI on electrolytes upon battery cycling. (a) 19F image evolution of electrolyte upon cycling 43. (b) 7Li image of electrolyte 46. (c) 7Li MRI of both electrolyte and Li electrodes 64. (d) 7Li image of a solid symmetric Li/LGPS/Li battery for Li distribution and reason for increased resistance 70 (a) Adapted from Ref. 43. (b) Reprinted with permission from Ref. 46, Copyright (2016) American Chemical Society. (c) Reprinted with permission from Ref. 64, Copyright (2015) American Chemical Society. (d) Reprinted with permission from Ref. 70, Copyright (2018) American Chemical Society."

Fig 6

(a) Electrochemical cell for operando EPR study. The surrounding quartz glass tube is not shown. The in situ EPR spectra at the pristine, at the end of the first cycle, and at the end of the last 3C cycle are presented in (b), (c) and (d), respectively. Black and red curves are noted as the electrolyte without and with FEC additive 87 (a–d) Reprinted with permission from Ref. 87, Copyright (2015) Royal Society of Chemistry. "

Fig 7

(a) Picture and schematic of a LMO/Li half-cell battery for operando EPR studies. The whole battery is located in the center of the resonator cavity of an EPR spectrometer, with a connection to a galvanostat for electrochemical operation. (b) CW-EPR spectrum of the pristine battery and its constituents, pure LMO, LMO mixed with conductive additive, and Li metal. (c) Schematic of the interactions within LMO cathode and its time evolution upon battery cycling 88 (a–c) Reprinted with permission from Ref. 88, Copyright (2017) American Chemical Society."

Fig 8

(a) Picture of a LRSO/Li half-cell battery for in situ EPR image (EPRI) studies with cycling curves shown on the top-right corner 86. The whole battery is located in the center of the resonator cavity of an EPR spectrometer, with a connection to a galvanostat for electrochemical operation. (b–e) in situ EPR images (EPRI) of the LRSO/Li battery under different cycling states as marked in (a). (f) Thick lithium metal with mechanical stamp and its corresponding EPR image as shown on the top 89. (g) EPR image of lithium dendrites formed in a glass fiber separator 89. (a–e) Reprinted with permission from Ref. 86, Copyright (2015) Springer Nature. (f–g) Reprinted with permission from Ref. 89, Copyright (2018) Springer Nature. "