Fig. 1

Schematic diagram of magnetic-field regulation for structure and performance optimization in LIBs"

Fig. 2

(a) Schematic diagram of electrode coating process and magnetic field effect under external magnetic field[18]; (b) Deintercalation mechanism of LCO arranged along (010)[18]; (c) High-resolution transition electron microscopy (HRTEM) images of LFP monocrystalline platelets (LFP-P)[28]; (d) X-ray powder diffractometer (XRD) pattern for the horizontal magnetic field–oriented NCM622 cathode (HMFC)[31]; (e) Schematic diagram of the phase transition mechanism for a specific disordered phase[32]"

Fig. 3

(a) Magnetic field-induced vertical alignment of graphite flakes [19]; (b) Scanning Electron Microscope (SEM) image of vertical graphite aligned electrode[19]; (c) Performance comparison of vertically aligned graphite electrodes[19]; (d) Evolution of the specific charge at 2C as a function of angle between graphite flakes and current collector[19]; (e) Schematic diagram of the preparation of magnetic field-induced orientation of CPE composite polymer films[37]."

Fig. 4

(a) Magnetic field promotes the electronic transition of Co in Carbon nanofiber/cobalt sulfide (CNF/CoS) electrodes from low spin state to high spin state[17]; (b) Schematic diagram of the suppression of lithium dendrite growth by the MHD effect[20]; (c) Schematic diagram of the mechanism of lithium dendrite growth suppression by magnetic fields in different directions[21]; (d) Toroidal magnetic field induced a LiF-rich 3D SEI framework[47]"

Fig. 5

(a) Cyclic stability with magnetic field during single charging at 501st, 1001st, 1501st and 1751st cycles at 5 A/g[52]; (b) Energy density versus power density plots for magnetic Li3(V1-xFex)2(PO4)3[53]"

Fig. 6

(a) A schematic diagram of the ion distribution regulation by Co/ZnO magnetic current collector[55]; (b) Schematic illustration of the regulation of Li deep plating by CC@CoF2/C is analogous to the removal of “apical dominance” in plants[56]; (c) A schematic diagram of the restriction of Fe nanoparticles aggregation in a strong magnetic environment by Ni/Fe3O4@C NTAs anode[57]"

Fig. 7

Morphologies of lithium anode after CE test at a current density of 1.0 mA/cm2: (a) bare Cu, (b) magnetic SEI (PVDF@γ-Fe2O3) with content of magnetic particles of 40 :1[58]; In-situ optical microscopy images of Li deposition on (c) Co-spc-COP and (d) bare Li versus prolonged discharging time at 3 mA/cm2[59]"

Fig. 8

(a) X-ray photoelectron spectroscopy (XPS) spectra of lithium anode after cycling with/without magnetic field[60]; (b) SEM images of CN-NK[61]; (c) Scanning transmission electron microscopy (STEM) images of CN-NK[61]; (d) The voltage profiles of symmetric cells at 10 mA/cm2 and 1 mAh/cm2[61]"

Table 1

The mechanism of intrinsic magnetic field regulation"

Fig. 9

(a) Li dendrite growth morphology at 10 mA/cm2current density under an external magnetic field[49]; (b) In-situ FT-IR transmittance spectra of spc-COP and Co-spc-COP on charging/discharging process of symmetric cells[59]; (c) In-situ Raman spectra and the corresponding voltage-time profiles in asymmetric cells based on Li@Co-spc-COP[59]; (d) In-situ XPS etching tests for C, F, N, and O elements and element content distribution[47];"

Fig. 10

(a) Phase-field simulation of the evolution of Li dendrite structure: the phase field, the Li+ concentration field, and electric potential field from top to bottom[49]; (b) Simulation results of the different trajectory of Li+ during deposition process without or within magnetic field. The right scale represents the timeline[20]; (c) Boxplot snapshots of the electrolyte from molecular dynamics simulations at 0 and 8 T[48]; (d) COMSOL simulations of Li deposition at 0 and 8 T[48]; (e) the cLi distribution and morphology evolution for the control case and the battery under 0.8 T in COMSOL simulation[46]; (f) The distributions of X-, Y-, and Z- current densities(Jx, Jy, and Jz ) distributions in the electrochemical chamber with the 3D magnetic field[61]"