A high‐capacity dual‐ion full battery based on nitrogen‐doped carbon nanosphere anode and concentrated electrolyte

Dual‐ion batteries (DIBs) are often criticized for their low discharge capacity and poor cyclic capability despite their inherent high working voltage, low manufacturing cost, and environmental friendliness. To solve these shortcomings, many attempts and efforts have been devoted, but all ended in unsatisfactory results. Herein, a hierarchical porous carbon nanosphere anode with ultrahigh nitrogen doping is developed, which exhibits fast ion transport kinetics and excellent Li+ storage capability. Moreover, employing a concentrated electrolyte is expected to bring a series of advantages such as stable SEI for facilitating ion transmission, enhanced cycling performance, high specific capacity, and operation voltage. These advantages endow the assembled full DIBs with excellent performance as a super‐high specific discharge capacity of 351 mAh g−1 and can be cycled stably for 1300 cycles with Coulombic efficiency (CE) remaining at 99.5%; a high operating voltage range of 4.95–3.63 V and low self‐discharge rate of 2.46% h−1 with stable fast charging‐slow discharging performance. Through electrochemical measurements and physical characterizations, the possible working mechanism of the proof‐of‐concept full battery and the structural variations of electrodes during cycling are investigated. The design strategy of novel battery system in this work will promote the development of high‐performance DIBs.

costs. [4][5][6] In contrast, dual-ion batteries (DIBs) can make use of graphite as both the anode and cathode, and its unique anion intercalation mechanism endows a high working voltage and energy density, which make up for the shortcomings of LiBs. [7][8][9][10] However, it is difficult to realize the practical application of DIBs. A key point to be illustrated is the great demand for anodes since graphite anodes exhibit scanty sites for Li + storage and poor cycle performance. [11][12][13] Compared with graphitized carbon, amorphous carbon doped with heterogeneous elements formed by high-temperature pyrolysis generally display some unexpected properties: (1) Defects generated during pyrolysis can be regarded as active sites to store Li +14-17 ; (2) Emerging greater layer spacing, which achieves rapid transmission of Li + and a high (de) lithiation rate 18-20 ; (3) Doped heterogeneous elements help to improve structural stability and ionic conductivity with additional Li + storage sites. [21][22][23] Nitrogen doping of amorphous carbon is a representative strategy to fulfill high capacity, long life and an excellent rate carbonaceous anode. [24][25][26][27][28] Currently, template-assisted pyrolysis is usually used to synthesize 3D nitrogen-doped carbon (3D-NDC) anodes. [29][30][31][32] For instance, Yang et al. used zinc oxide nanospheres and polyacrylonitrile as the hard template and precursor to prepare an unpyrolyzed electrospun membrane by the electrospinning method, and then obtain the necklace-like porous 3D-NDC (NHC 2 -NH 3 /Ar) by pyrolyzing in NH 3 and Ar atmospheres sequentially. 30 The stable cycling proficiency of the NHC 2 -NH 3 /Ar electrode is demonstrated by showing a reversible capacity of 161.3 mAh g −1 after more than 1600 cycles at 1000 mA g −1 . Ge et al. uniformly mixed g-C 3 N 4 with zinc powder, followed by two-step pyrolysis at 500°C and 800°C in argon. 31 Finally, the metal ions were removed with acid to obtain a 3D-NDC microsphere with hierarchical structure (CMSs). The assembled full battery based on CMSs anode delivers a retention rate of 78% for 1900 cycles at 500 mA g −1 . Xiong et al. synthesized a nitrogen/oxygen dual-doped carbon (NOHPHC) by pyrolyzing and etching a type of metal-organic framework based on a self-template method. 32 Therefore, the NOHPHC electrode exhibits a capacity of 123 mAh g −1 after 1100 cycles with a retention rate of 69.5%. However, the above synthesis strategies based on the template method are cumbersome and complicated, and difficult to guarantee the purity. An ideal tactic is to prepare the 3D-NDC anode with hierarchical porous structure through one-step direct pyrolysis of the homologous precursor. [33][34][35][36] Zhang et al. prepared accordion-shaped 3D-NDC by directly pyrolyzing uric acid powder at 900°C, the special layered carbon structure can suppress volume expansion to improve stability. 33 Qiu et al. directly pyrolyzed g-C 3 N 4 at 700°C to obtain layered 3D-NDC, which had excellent Li + storage capability with a fast rate. 34 Alshareef et al. obtained 3D-NDC by directly pyrolyzing (pyromellitic acid-melamine) PMA-MA supramolecules at 750°C, which were composed of carbon nanosheets and disordered crystal structure with ultrahigh edgenitrogen-doping of 16.8 at%. 35 The full battery with the 3D-NDC electrode can release a high capacity of 241 mAh g −1 after 100 cycles with a low self-discharge rate of 0.088% per hour.
A crucial point in the exploitation of highperformance dual-carbon lithium-based full batteries is the demand for an appropriate electrolyte system, since electrolyte is the single source of active ions required to maintain a sufficiently high concentration. 37,38 Conventional low concentration (<1 M, 1 M = 1 mol/L) electrolytes based on ethylene carbonate (EC) usually exhibit suboptimal performance: poor cyclic stability due to the continuous decomposition of electrolyte under the high voltage and fragile (solid electrolyte interface) SEI 39 ; low discharge capacity because of the co-intercalation of EC molecules. 40,41 Interestingly, concentrated electrolytes usually display outstanding performances: The formed sturdy SEI is conducive to the (de)intercalation of active ions 42 ; Reduce the potential of the anion intercalated into graphite cathode and improve the reduction stability 43 ; Provide enough active ions, which is expected to deliver a high discharge capacity. 44 In addition, ionic liquids (ILs) are ideal candidate solvents because of their wide electrochemical window, nonflammability, and avoidance of solvent molecular co-intercalation. [45][46][47] Nevertheless, considering the high viscosity and low solubility of ILs, it is a satisfactory choice to combine the respective superiorities of organic solvents and ILs for exploiting a novel organic solvent-ILs mixed electrolyte, which is promised to bring unexpected electrochemical performance.
Herein, an innovative immediate pyrolysis strategy is shared for the preparation of 3D-NDC nanosphere anode (3D-NDCS) with a layered porous structure. Matched with concentrated organic-IL mixed electrolyte (4 M EMC-Pyr 14 TFSI − 5%ES) and natural graphite (NG) cathode, the assembled full battery (3D-NDCS//NG-DIB) exhibits high discharge specific capacity, excellent rate capability, and stable cyclic performance. Moreover, through a series of physical and electrochemical characterizations, the Li + storage mechanism of 3D-NDCS and the structural variations in different charging-discharging stages are investigated, and some opinions on whether the DIB of this system can be realized in practical applications are put forward.

| Chemical preparation
Nitrogen-doped carbon was synthesized by direct pyrolysis of melamine foam. First, melamine foam was placed in a corundum crucible with a lid, then the crucible was put into a tube furnace filled with argon, and the temperature was programmed to 1000°C for 2 h with a heating rate of 5°C/min. After cooling, the sample was fully ground uniformly, and the obtained powder is directly used as the anode without further purification.

| Physicochemical characterization
Scanning electron microscope (SEM) images and energydispersive X-ray spectroscopy (EDS) images were taken on a SEM (ZEISS). The SEM and EDS of the 3D-NDCS sample was tested using an aluminum plate as a substrate. X-ray diffraction (XRD) patterns were collected on a D8 Advance X-ray diffractometer (Bruker) with a Cu Kα radiation (λ = 1.5406 Å). Power XRD was recorded in the 2θ (5°−90°, 10°/min) with a Cu-Kα radiation (40 kV, 40 mA). Raman spectra were collected on a LabRAM ARAMIS micro-Raman spectrometer (Horiba-Jobin Yvon) using a cobalt laser (473 nm) with a 1% filter. Fourier-transform infrared spectra (FTIR) was collected on a Nicolet iS10 FTIR spectrometer (ThermoFisher Scientific). X-ray photoelectron spectroscopy (XPS) analysis was conducted on a Kratos Axis Supra photoelectron spectrometer (Shimadzu). The specific surface areas and pore size distributions were evaluated by N 2 adsorption isotherms tested by an ASAP 2420 adsorption/desorption analyzer (Micrometrics).

| Electrode preparation and electrochemical tests
The NG cathode was prepared by adding NG powder (3000 mesh), acetylene black (AB), and polyvinylidene fluoride (PVDF) into a weighing bottle containing N-methyl-pyrrolidone (NMP) solvent (90:2:8, w/w/w), stirring overnight until uniformly mixed. Then the prepared slurry was poured onto the aluminum foil, and the film was then coated evenly with a film applicator to a thickness of 200 μm. Finally, it was placed into a vacuum-drying oven to dry overnight at 100°C. Similarly, the 3D-NDCS anode was prepared like the NG cathode with the mass ratio of 7:2:1, and the thickness was 100 μm. Both of the NG cathode and 3D-NDCS anode were cut into wafers (diameter: 14 mm). In addition, the active materials loading of the anode and cathode were~1.0 and 2.0 mg/cm 2 , respectively.

| RESULTS AND DISCUSSION
As shown in Supporting Information: Scheme S1, melamine foam was used for the first time as a carbon precursor for the direct pyrolysis synthesis of 3D-NDCS. Different from powdered melamine, foamed melamine displayed a porous network structure, which was conducive to the formation of 3D porous carbon skeletons during pyrolysis. Finally, the carbon skeleton gradually collapsed and polymerized when heated, forming a 3D porous sphere. In addition, the nitrogen content of melamine accounted for a high proportion of 66.7%, which is expected to bring high nitrogen doping. Supporting Information: Figure S1 shows the SEM image of melamine foam after pyrolysis at 1000°C. The overall shape formed by the arrangement of rows of spheres, specifically, each column presents a candied hawslike string morphology composed of nano-sized porous spheres with a diameter of 40-60 nm, which helps to improve the transmission kinetics of active ions and ensure the adequate infiltration of electrolyte. The broad typical peak (002) with low peak intensity indicates the imperfect alignment of 3D-NDCS with large layer spacing ( Figure 1A), which is caused by the formation of amorphous structure due to the release of pyrolysis gas during the carbonization process of melamine foam. 33,34 The R value reflecting the crystallinity of amorphous carbon introduced by Dahn is 3.36, indicating a low crystallinity with a high disorder of 3D-NDCS. 48 It can also be proved from the Raman spectrum that the G band at~1580 cm −1 is quite weak, and the value of I D /I G is 1.01, shows the large amount of defects and high amorphous state of 3D-NDCS ( Figure 1B). 49 The results of EDX mapping represent an ultrahigh nitrogen doping content of 36.46% ( Figure 1C and Supporting Information: Figure S2), which is significantly higher than most reported nitrogen doping levels. It can be proved from the FT-IR analysis in Supporting Information: Figure S3 that the broad absorption peak around 1130 cm −1 is attributed to the stretching vibration of C-N bond, and the absorption peaks near 1560 and 1655 cm −1 are associated with C═N and N-H bond, 50,51 respectively. Figure 1C suggests that C, N, and O elements are uniformly distributed. The relative ratios of pyridine nitrogen (N6), pyrrole nitrogen (N5), graphitized nitrogen (NQ), and nitrogen oxide (NO) obtained via fitting high-resolution N1s XPS spectra are 42.3%, 39.5%, 14.0%, and 4.2%, respectively, with a high proportion of 81.8% for edge-nitrogen (N6 and N5), which is of great significance to improve the Li + storage capacity of 3D-NDCS ( Figure 1D). 32,34,52 Remarkably, Figure 1E shows a hierarchical pore distribution of micropores, mesopores and macropores for 3D-NDCS, which helps to store more active ions. In addition, the low BET-specific surface area of 16.731 m 2 /g is expected to ensure sufficient contact with the electrolyte and inhibit the occurrence of parasitic reactions ( Figure 1F), thus forming a steady SEI film. 53,54 The Li + storage capability and electrochemical performance of the 3D-NDCS electrode was investigated by CV scanned between −5.0 and −2.5 V, Figure 2A shows the CV curves at a scan rate of 0.3 mV/s. The reduction peaks near −2.8 and −3.2 V in the first circle can be attributed to the decomposition of electrolytes for the formation of SEI. 55,56 Notably, they disappear in subsequent cycles, indicating the stability of SEI. Two pairs of redox peaks near −4.8 and −4.2 V correspond to the electrochemical reaction process. Moreover, all the curves except the first cycle coincide, indicating that the storage of Li + is a stable and reversible process. 49,57 The GCD curve of 3D-NDCS//NG-DIB at 1C (1C = 100 mA g −1 ) displays typical active ion (de)intercalation characteristics with two pairs of charge/discharge plateaus ( Figure 2B), matching with the redox peaks in CV curves (Figure 2A). Figure 2C exhibits the corresponding dQ/dV differential profile where each peak is consistent with the platform in the GCD curve. different stages of Li + deintercalation from 3D-NDCS. Furthermore, the 3D-NDCS//NG-DIB displays an operating voltage range of 4.95-3.63 V with a medium discharge voltage (V m ) of 4.28 V, which is much higher than commercial LiBs. To explore the Li + storage behavior and kinetics of the 3D-NDCS electrode, CV curves based on different scan rates have been obtained ( Figure 2D). Specifically, these curves present a rectangular-like shape with clear redox peaks, indicating the synergistic effect of diffusion and capacitive behavior. 61 This synergistic effect can be quantitatively analyzed based on the power-law relationship between i (peak current) and v (scan rate): i = av b , where the value of b between 0.5 and 1 can be determined by plotting log (i) versus log(v), the b value close to 0.5 or 1 meaning a diffusion-controlled or capacitive-controlled process, respectively. 62,63 Figure 2E shows the b values of the anodic and cathodic peaks are calculated to be 0.8226 and 0.8108, respectively, indicating that the kinetics of 3D-NDCS is mainly attributed to the capacitivecontrolled process. Quantitatively, the mixed mechanisms can be divided into two separate mechanisms at a fixed potential by i(V) = k 1 v + k 2 v 1/2 , where k 1 and k 2 are constants, k 1 v and k 2 v 1/2 represent capacitance contribution and diffusion contribution, respectively. 64 As shown in Figure 2F, correspondingly, the capacitance contribution to Li + storage at 0.1 mV/s is 0.738. In addition, it increases to 0.829, 0.863, and 0.882 as the scan rates increase to 0.3, 0.5, and 0.7 mV/s, respectively.
To further investigate the rate capability and cyclic performance of 3D-NDCS//NG-DIB, a proof-of-concept full battery based on a 4 M concentrated electrolyte and a 3D-NDCS anode is constructed. Figure 3A demonstrates the typical GCD curves at different current densities from 1 to 15 C with voltage range of 2.5-5.0 V. As the current density increases, a slight charge-discharge plateau separation is observed, indicating the occurrence of electrochemical polarization. It can be proved from the dQ/dV differential curves in Supporting Information: Figure S4 that as the rate increases, the oxidation/reduction peaks shift to a high/low potential with the peak intensities decreasing. 49,65 Nevertheless, the separation is slow with the voltage platforms corresponding to the (de)intercalation of active ions still being clearly examined, indicating the weak polarization and fast kinetics behavior. Moreover, specific discharge capacities (SDC) of 335, 278, 242, 223, 185, and 156 mAh g −1 can be delivered at the rate scope of 1, 2, 3, 5, 10, and 15 C ( Figure 3B), the SDC can be restored to its initial value and cycled stably when the rate returns to 2 C, demonstrating the reversibility and rate capability of 3D-NDCS//NG-DIB. For comparison, we also assembled a full DIB based on diluted electrolyte of 1 M, which displays unsatisfactory performance compared with concentrated electrolyte. As well as the increase of current density, the polarization becomes more serious and the charge/discharge plateaus tilt (Supporting Information: Figure S5). Only 163, 142, 119, 88, 63, and 49 mAh g −1 achieved at 1, 2, 3, 5, 10, and 15 C, respectively (Supporting Information: Figure S6). Figure 3C shows the cycling performance of 3D-NDCS//NG-DIB based on concentrated/diluted electrolyte at 1 C. On the one hand, the initial specific discharge capacity (ISDC) based on concentrated electrolyte is as high as 351 mAh g −1 , and the capacity retention rate (CRR) of 95% after 80 cycles. Furthermore, the GCD curves of various cycles basically overlap ( Figure 3D), indicating outstanding cyclic stability, which showcases the best performance of DIBs reported so far. On the other hand, an ISDC of 148 mAh g −1 based on diluted electrolyte is released, then decreases continuously in subsequent cycles with a limited SDC of 66 mAh g −1 obtained after 80 cycles. The GCD curves display poor cyclic stability and serious polarization with disappearing charge/ discharge plateaus as shown in Supporting Information: Figure S7. The enormous discrepancy mainly benefits from the formation of sturdy SEI via the use of concentrated electrolyte. Research by Yamada et al. have shown that concentrated electrolytes are not only beneficial to the rapid transport of Li + and steady circulation, but also inhibit the further decomposition of electrolyte and occurrence of side reactions, resulting in better electrochemical performance. 42,43,66,67 This can be inferred from the Nyquist plots based on EIS in Figure 3E and Supporting Information: Figure S8, the intermediate frequency semicircle represents the charge transfer resistance (Rct) at the electrode/ electrolyte interface. The initial Rct based on concentrated electrolyte is slightly larger than that of diluted electrolyte, which is owing to the higher viscosity of high-concentration electrolyte. Interestingly, the Rct of diluted electrolyte is significantly higher than that of concentrated electrolyte in subsequent cycles. This is caused by the utilization of diluted electrolyte resulting in a fragile SEI, which will lead to the continuous decomposition of electrolyte and the formation of SEI. Besides, the 3D-NDCS//NG-DIB based on concentrated electrolyte exhibits a quite stable V m up to 4.2 V during the long-cycling process ( Figure 3F). As the rate up to 4 C, the ISDC based on concentrated electrolyte is 255 mAh g −1 with no capacity fade after 200 cycles, while the ISDC based on diluted electrolyte is only 110 mAh g −1 with a CRR of 71% (Supporting Information: Figure S9). Surprisingly, the battery still shows superior electrochemical performance even at a high rate of 15 C. The ISDC is 166 mAh g −1 , and it can be continuously cycled for 1300 cycles without capacity degradation with the CE maintains at~99.5%. While the ISDC of 46 mAh g −1 based on diluted electrolyte is much less than that of concentrated electrolyte and decays continuously to 36 mAh g −1 after 1300 cycles, signifying a poor cycling performance. Severe self-discharge will limit further practical application, especially in dual-graphite or dual-carbon systems, where the batteries usually deliver a serious self-discharge rate. [68][69][70] Therefore, the self-discharge performance was conducted. First, charging the full battery to the upper cut-off voltage of 5.0 V, and then discharging it after resting for 24 h. Figure 4A,B shows the voltage-time curves of (un)resting, the battery still maintains a voltage of 4.41 V after resting. Consequently, the self-discharge rate of the system is calculated as 2.46% h −1 , which is considerably lower than that of the reported DIBs. In addition, stable fast charging and slow discharging can not only shorten the charging time, but also increase the usage time of batteries. Therefore, the performance was tested by fast charging at an ultrahigh rate of 20 C, then slowly discharged at a low rate of 1 C to investigate the cyclic stability. The first 10 cycles of fast charging-slow discharging shows that the battery is fully charged within 5 min, while the discharging time exceeds 100 min ( Figure 4C). Besides, the ISDC reaches 176 mAh g −1 and steadily increases to 186 mAh g −1 after 300 cycles ( Figure 4D). This results in excellent fast charging-slow discharging performance, indicating that this dual-ion full battery system shows excellent stability with great potential for further practical application.
To elucidate the working mechanism of 3D-NDCS// NG-DIB. XPS was performed to characterize and analyze the elements of electrodes during the GCD processes, and the corresponding results are presented in Figure 5. Figure 5A shows the high-resolution Li 1 s spectrum. A sharp Li 1 s characteristic peak appears at the fully charged stage, indicating the intercalation of Li + . 55 After being fully discharged, the characteristic peak disappears completely, which means the reversible (de)intercalation of Li + . Moreover, a distinct F 1 s characteristic peak appears after being fully charged ( Figure 5B). According to the previous work, which is due to the sharp decrease of free solvent molecules in the concentrated electrolyte, the anion (TFSI − ) preferentially decomposed to form a robust SEI. 42,43,66,67,[71][72][73] As shown in the high-resolution C 1 s spectrum ( Figure 5C), the C-N characteristic peak significantly strengthened. 52,74 Besides, a new characteristic peak corresponding to the decomposition of TFSI − appears. 75 After being fully discharged, the characteristic peaks of F 1 s and C-N remains basically unchanged, while the decomposition peak of TFSI − weakened, indicating the formation of a robust SEI that no longer consumed electrolyte. As for NG cathode, the highresolution S 2p spectra appears after being fully charged because of the intercalation of TFSI − ( Figure 5D), which becomes weaker with the deintercalation of TFSI − after being fully discharged. Furthermore, the (de)intercalation of TFSI − at NG cathode can be demonstrated from the FT-IR spectra based on pristine and fully charged/ discharged stages. As shown in Figure 5E, stretching vibration peaks corresponding to C-S, S═O, C-F, and N-H appears at~1047, 1127, 1188, and 1324 cm −1 , respectively after being fully charged, implying the intercalation of TFSI − . 61,65,76 Then all the characteristic peaks are significantly weakened due to the deintercalation of TFSI − after being fully discharged. Combined with the XRD results (explained in the following section), the remaining signal peaks are mainly due to the residual electrolyte and the decomposition of TFSI − and ES to form a CEI on the surface of cathode, just as there are still strong N-S (Supporting Information: Figure S10), LI-F (Supporting Information: Figure S11) and TFSIdecomposition peaks (Supporting Information: Figure S12) after being fully discharged.
Combined with the above analysis, the working mechanism of the full battery is shown in Figure 6, and the electrode reactions involved are as follows: where A represents Anode. Overall : C + Li + C + TFSI C (TFSI) + C (Li).
XRD and Raman characterizations were performed to further explore the (de)intercalation behavior of Li + / TFSI − with the concentrated electrolyte at the selected charged/discharged states. Figure 7A shows the corresponding time-voltage curve of the full battery for XRD measurement. As for NG cathode, the intensity of 002 characteristic peak at 26.5°gradually decreases during the charging process ( Figure 7B), and a new characteristic peak is split after being fully charged, which is caused by the formation of graphite intercalation compounds, corresponding to a layer spacing of 3.9 Å with intercalation stage of 1. [77][78][79] The split peak disappears during the subsequent discharging process, while the 002 peak recovers to its original intensity after being fully discharged. Moreover, it remains a comparable intensity to the pristine peak even after 200 cycles, indicating an outstanding reversibility of the (de)intercalation process with excellent structural stability of NG. The Raman spectra of cathode in Figure 7E can also corroborate the reversible (de)intercalation of TFSI − . The D band and G band are located at~1360 and~1580 cm −1 represent the defects and sp2 carbon atomic plane vibrations of the graphitic layer, respectively, and the ratio of I D /I G is usually used to measure the disorder degree of F I G U R E 4 Self-discharge and fast charging-slow discharging performance test. Galvanostatic charge-discharge curves of (A) Unresting and (B) Resting for 24 h. (C) The first 10 cycles of charging at 20 C and discharging at 1 C and (D) Corresponding cycle performance for 300 cycles.
graphite. 49,69,73 The I D /I G ratio gradually increases during the charging process, representing a reduction of the crystallinity due to the intercalation of TFSI − . During the following discharging process, the I D /I G ratio gradually decreases and the crystallinity of graphite recovers with the deintercalation of TFSI − . For 3D-NDCS anode, as shown in Figure 7C, the 002 peak gradually decreases with the continuous intercalation of Li + during the charging process. In the meantime, the D band in the Raman spectrum continuously enhances, accompanied by an increase in the I D /I G ratio ( Figure 7F), indicating the enhancement of layer spacing and disorder of anode. During the discharging process, the 002 peak returns to its original strength with the continuous deintercalation of Li + , which is manifested in the decrease of D band and I D /I G ratio, and the crystal structure of anode gradually recovers. Remarkably, all characteristic peaks do not shift during the entire process, and still maintain the comparative intensity to pristine peak after 200 cycles, proving the excellent reversibility of (de)intercalation and splendid structural stability.
The structure and morphological evolution of electrodes after 200 cycles were investigated by SEM. On one hand, Supporting Information: Figure S13a,b shows the SEM images of NG cathode after 200 cycles. The lamellar structure of graphite can be clearly seen without any volume expansion and structural exfoliation, which proves the structural stability of NG. On the other hand, the surface morphology and structure of the anode after 200 cycles are shown in Supporting Information: Figure S13c,d, the complete 3D spherical structure is still displayed, indicating the splendid cyclic stability, which is consistent with the conclusion of XRD and Raman in Figure 7.

| CONCLUSION
The high-nitrogen-doped hierarchical porous carbon nanosphere anode was synthesized by a one-step direct pyrolysis method, which shows fast ion transport kinetics and excellent Li + storage performance. Besides, the adoption of concentrated electrolyte is conducive to the formation of stable SEI and improves the intercalation capacity with reversible transmission of active ions. The constructed full battery exhibits a series of excellent electrochemical performances: (1) A super-high ISDC of 351 mAh g −1 at 1 C with a CRR of 95% after 80 cycles; (2) The ISDC is 166 mAh g −1 at a high rate of 15 C and can be cycled stably for 1300 cycles with CE remains at 99.5%; (3) A high operating voltage range of 4.95-3.63 V and high median discharge voltage of 4.2 V; (4) Low selfdischarge rate of 2.46% h −1 and stable fast charging (fully charged within 5 min) and slow discharging (up to 100 min during discharge). The working mechanism of 3D-NDCS//NG-DIB is explained by XPS and FT-IR, and the excellent structural stability of electrodes is demonstrated by XRD, Raman and SEM, which is one of the reported DIBs with best preponderance. It is expected to shed light on the development of high-performance and large-scale practical application in the future for DIBs. Wenhui Yuan: Writing-review and editing, supervision, project administration, funding acquisition, and resources. The manuscript was written through the contributions of all authors. All authors have given approval to the final version of the manuscript.