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1 advances.sciencemag.org/cgi/content/full/3/12/eaao7233/dc1 Supplementary Materials for Ultrafast all-climate aluminum-graphene battery with quarter-million cycle life Hao Chen, Hanyan Xu, Siyao Wang, Tieqi Huang, Jiabin Xi, Shengying Cai, Fan Guo, Zhen Xu, Weiwei Gao, Chao Gao This PDF file includes: Published 15 December 2017, Sci. Adv. 3, eaao7233 (2017) DOI: /sciadv.aao7233 fig. S1. Additional information for cathode material design, preparation, and characterizations. fig. S2. Raman spectra, XRD patterns, and XPS spectra of GF-HC, GF-p, GF-Hp, and expanded graphite. fig. S3. HRTEM images of expanded graphite and GF-HC. fig. S4. SEM images of GF-HC, GF-p, and GF-Hp. fig. S5. Orientation demonstration of GF-HC and graphene foam with statistic of cracks in different GF cathodes. fig. S6. Porosity characteristics of GFs. fig. S7. Permeability test of ionic liquid electrolyte on GF-HC and GF-Hp in a glove box. fig. S8. Dynamic contact angle test of DMF droplet on different GF cathodes. fig. S9. Mechanical properties of GF. fig. S10. CV and cutoff voltage optimization of the GF-HC cathode. fig. S11. Cycling performances of GF-HC and GF-p. fig. S12. EIS and CV spectra of GF-HC, GF-p, GF-Hp, and graphite. fig. S13. Element mapping of the charged GF-HC cathode. fig. S14. Electrochemical performance of the GF-HC cathode at low rates. fig. S15. Charge/discharge curves of the GF-HC cathode at different temperatures. fig. S16. Charge/discharge curves of the GF-HC cathode and ionic conductivity of [EMIm]AlxCly ionic liquid electrolyte at low temperature. fig. S17. Comparison of electrochemical performances of GF-HC and GF-p cathodes at low temperature.

2 fig. S18. Photograph of flexible Al-GB. fig. S19. EIS spectra of flexible Al-GB soft pack cell after different bending cycles. fig. S20. Additional information on coin cell fabrication, demonstration for the absence of side reaction, and the electrochemical performance based on mass loading. fig. S21. Galvanostatic cycling of the GF-HC cathode with [Et3NH]AlxCly electrolyte. table S1. Electrochemical properties of electrode materials from various reports. Calculations of AlCl4 diffusivity based on CV plot Calculations of AlCl4 diffusivity based on EIS data References (50, 51)

f fig. S1. Additional information for cathode material design, preparation, and characterizations. (A) The fabrication mechanism of GF-HC, GF-p and GF-Hp.

3 f fig. S1. Additional information for cathode material design, preparation, and characterizations. (A) The fabrication mechanism of GF-HC, GF-p and GF-Hp. The gas pressure caused by deoxygenating reaction during annealing created interconnected channels in GF-HC (under relax state while annealing). Meanwhile the GF-p and GF-Hp (under mechanical pressure while annealing) afforded less fissures, channels or even plain surface due to guided gas releasing direction. (14) (B) Photograph of a roll of GF- HC demonstrating its good flexibility and processibility. (C) XRD patterns of GF-HC.

4 fig. S2. Raman spectra, XRD patterns, and XPS spectra of GF-HC, GF-p, GF-Hp, and expanded graphite. (A-C) Raman spectra (A), XRD patterns (B) and XPS spectra (C) of GF-p and GF-Hp, revealing similiar chemical structure to GF-HC. (D-F) C1s peak of XPS spectra of GF-HC (D), GF-p (E) and GF-Hp (F). (G) Raman spectra of expanded graphite showing highly stacked graphite-like 2D peaks with low 2D1 component. (H) Raman spectra of GF-HC showing few-stacked graphene-like 2D peaks with high 2D1 component (50).

5 fig. S3. HRTEM images of expanded graphite and GF-HC. (A-C) HRTEM images of expanded graphite showing highly stacked structure (>>20 layers stacking). (D-L) HRTEM images of GF-HC showing few-stack graphene structure (2-9 layers stacking).

fig. S4. SEM images of GF-HC, GF-p, and GF-Hp. (A-C) SEM images of GF-HC. (A) Magnified SEM image of GF-HC corresponding to Fig. 2F, revealing highly aligned graphene sheets.

6 fig. S4. SEM images of GF-HC, GF-p, and GF-Hp. (A-C) SEM images of GF-HC. (A) Magnified SEM image of GF-HC corresponding to Fig. 2F, revealing highly aligned graphene sheets. (B) Sloping cross-section SEM image of GF-HC showing the fissures in the surface of GF-HC, which were boundaries of graphene sheets. (C) Cross-section SEM image of GF-HC. (D-F) SEM images of GF-p, revealing fewer channels and fissures than GF-HC. (G-I) SEM images of GF-Hp, revealing even fewer channels and fissures than GF-p.

7 fig. S5. Orientation demonstration of GF-HC and graphene foam with statistic of cracks in different GF cathodes. (A) SEM image of graphene foam, revealing these graphene sheet components are non-oriented. (B) Small-angle X-ray scattering (SAXS) analysis of GF-HC revealing existance of orientation in the graphene sheets of GF-HC. (C) SAXS analysis of graphene foam revealing absence of orientation. (D) Distribution of the cracks number in each SEM image of graphene film cathode surface, summarized from 100 pieces of SEM images (400 μm*270 μm).

8 fig. S6. Porosity characteristics of GFs. (A) Nitrogen adsorption-desorption isotherms of GF-HC, GF-p and GF-Hp. The specific surface areas were decreased from 3.1 m 2 g -1 for GF-HC, 2.42 m 2 g -1 for GF-p to 2 m 2 g -1 for GF-Hp. (B-D) Mercury intrusion porosimetry spectra for graphene films cathode in the macropore range. (B) Plot of cumulative intrusion volume versus pore diameter. (C) Pore size distribution and (D) Plot of incremental intrusion volume versus pore diameter. These plots show that GF-HC possess more large pores (diameter larger than 4 μm), so more mercury intrusion at larger pores (lower pressure) is achieved. The macroporosities of GF-HC, GF-p and GF-Hp are 67.8%, 60% and 54% respectively.

9 fig. S7. Permeability test of ionic liquid electrolyte on GF-HC and GF-Hp in a glove box. (A) Photograph of [EMIm]AlxCly ionic liquid electrolyte droplet on GF-Hp in glove box, after 18 hours there was no sign of wetting or permeation. (B) The reverse site of GF-Hp after 18 hours demonstrating no sign of permeation at all, which greatly differs with Fig. 2J. (C) The cross section of GF-HC with [EMIm]AlxCly ionic liquid droplet, exhibiting wet permeation area and smaller contact angle. (D-L) The cross section of GF- Hp with [EMIm]AlxCly ionic liquid droplet, exhibiting neglectable change in contact angle and permeation.

10 fig. S8. Dynamic contact angle test of DMF droplet on different GF cathodes. (A-E) for GF-HC. (F) Time-dependent variation of contact angle of DMF droplet on GF-HC. (G-I) for GF-p. (J-L) for GF-Hp.

11 fig. S9. Mechanical properties of GF. (A) Typical tensile stress curves of GF-HC. (B) Relative electric conductivities of GF-HC with different bending states. (C) Relative electric conductivities of GF-HC after repeated 180 o -bending for 600 times. R0 means initial resistance.

12 fig. S10. CV and cutoff voltage optimization of the GF-HC cathode. (A) CV of GF- HC cathode, revealing an apparent diffusion coefficient of 2.025*10-14 cm 2 s -1 calculated by the cathodic peak at 2.2 V according to Randles-Sevcik equation. The clear redox peaks demonstrate the cathodic electrochemical redox reaction instead of electrical double-layer capacitive behaviour. Based on the relationship between peak current and scan rate in sweep voltammetry, the cathodic peak at 2.25 V and anodic peak at 2.37V were mostly ascribed to the diffusion-controlled intercalation-based electrochemical redox reaction, while other peaks at lower potential were ascribed to pseudocapacitive behavior (25). (B) Charge/discharge curves of GF-HC cathode at different cut-off voltage. (C) Specific capacities and Coulombic efficiency of GF-HC cathode at different cut-off voltage, revealing 2.5 V is the optimal choice for cut-off voltage.

13 Calculations of AlCl4 diffusivity based on CV plot To evaluate the electrode kinetics of the graphene film cathodes, the AlCl4 - diffusivity (diffusion coefficient) was determined from the results of CV at various scan rates over the potential range of V at room temperature by the Randles-Sevick equation. In the typical CVs of the GF-HC cathodes at scan rate of mvs -1 (fig. S10A). The peak current (ip) in cathode samples (cathodic peak at 2.2 V in this study) was highly related to the square root of the scan rate (v) during the de-intercalation and intercalation of AlCl4 -, thus the electrochemical reaction rate would be controlled by a semi-infinite diffusion process. The diffusivity of the AlCl4 - at room temperature (25 C) can be calculated from Equation (1) as follows ip = n A D AlCl4 v 0.5 C 0 (1) where ip is the peak current (A), n is the number of electrons per reaction species, A is the apparent area of the electrode (cm 2 ), DAlCl4 is the diffusivity of AlCl4 - (cm 2 s -1 ), C0 is the bulk concentration of AlCl4 - in C18AlCl4 ( mol cm -3 derived from its theoretical density of 2.63 g cm -3, based on the enhanced weight and expanded layer ratio after stage-3 intercalation of AlCl4 - ion into graphene), and v is the sweep rate (V s -1 ) (51).

14 fig. S11. Cycling performances of GF-HC and GF-p. (A) Rate capabilities of GF-HC and GF-p cathodes at different low rates. The GF-HC cathode maintained remarkable specific capacity at relatively lower current densities: 115±3 mah g -1 at 0.1~2 A g -1 and 120 mah g -1 at 5 A g -1, which also overwhelmed those of GF-p: 93±2 mah g -1 at 0.1~2 A g -1 and 70 mah g -1 at 5 A g -1. (B) Corresponding charge/discharge curves of GF-HC cathode. (C) Corresponding charge/discharge curves of GF-p cathode. (D) Charge/discharge curves of GF-HC cathode corresponding to Fig. 3F at different cycles. (E) Specific capacity and Coulombic efficiency of defective GF-2500 cathode (annealled

15 at 2500 o C, ID/IG=0.05) and GF-1300 cathode (annealed at 1300 o C, ID/IG=1.2), delivering a lower capacity than defect-free GF-HC.

16 fig. S12. EIS and CV spectra of GF-HC, GF-p, GF-Hp, and graphite. (A) EIS spectra of GF-HC and GF-p. Calculated by the EIS spectra, the effective diffusion coefficient of GF-HC and GF-p cathode are 3 *10-14 cm 2 s -1 and 9.7*10-15 cm 2 s -1 respectively. (B) EIS spectra of GF-Hp. (C) CV spectra of GF-p at different scan rate, revealing an apparent diffusion coefficient of 8.1*10-15 cm 2 s -1. (D) CV spectra of graphite cathode at different scan rate, revealing an apparent diffusion coefficient of 4.71*10-15 cm 2 s -1. The diffusion coefficient of GF-HC is higher than highly stacked graphite and less channelled GF-p (8), supporting the "continuous active material" feature of GF-HC. (E) Relevant equivalent circuit model for EIS data.

17 Calculations of AlCl4 diffusivity based on EIS data EIS results are fitted using an equivalent circuit. In the equivalent circuit, Rs indicates the ohmic resistance; Rct is attributed to the charge-transfer resistance; CPE represents the double-layer capacitance and passivation film capacitance. W is the Warburg impedance caused by a semi-infinite diffusion of AlCl4 - ion in the electrode. Zre from EIS is highly related to the root square of the lower angular frequencies. Through linear fitting, the Warburg impedance coefficient (σw) can be obtained from the straight lines. The relation is governed by Eq. (2) Zre = Rs + Rct +σ w * ω -1/2 (2) After obtaining σw, the diffusivity values of the lithium ions diffusing into the electrode materials can be further calculated using Eq. (3) D AlCl4 = 0.5R2 T 2 (AF 2 Cσw) 2 (3) DAlCl4: AlCl4 - diffusivity, R: the gas constant, T: the absolute temperature, F: Faraday's constant, A: the contact area between active materials and electrolyte, and C: molar concentration of AlCl4 - ions (51).

fig. S13. Element mapping of the charged GF-HC cathode. (A) SEM image of charged GF-HC corresponding to those following element mapping images, scale bar: 160 μm.

18 fig. S13. Element mapping of the charged GF-HC cathode. (A) SEM image of charged GF-HC corresponding to those following element mapping images, scale bar: 160 μm. (B-H), corresponding element mapping of (B) aluminum, (C) chlorine, (D) carbon, (E) oxygen, (F) nitrogen, (G) calcium, and (H) silicon. Calcium and silicon comes from residue separator. Homogeneous distribution of Al, Cl and N species in GF- HC demonstrate the complete permeation of electrolyte into GF-HC cathode. (I) The total element distribution, demonstrating the element component of charged GF-HC. Absence of Fe, Cr or Ni supports no side reaction caused by stainless stell coin cell shell or nickel current collector.

(B) Corresponding charge/discharge curves.

19 fig. S14. Electrochemical performance of the GF-HC cathode at low rates. (A) Cycling performance of GF-HC cathode at 0.5 A g -1 and 0.2 A g -1. (B) Corresponding charge/discharge curves. (C) Specific capacity and (D) charge/discharge curves of GF- HC cathode at current densities of A g -1.

(B) Charge/discharge curves of GF-HC cathode at 80 o C with optimization on cut-off voltage.

20 fig. S15. Charge/discharge curves of the GF-HC cathode at different temperatures. (A) Charge/discharge curves of GF-HC cathode at 0 o C, 25 o C and 60 o C. (B) Charge/discharge curves of GF-HC cathode at 80 o C with optimization on cut-off voltage. (C) Charge/discharge curves of GF-HC cathode at 100 o C with optimization on cut-off voltage. (D) Charge/discharge curves of GF-HC cathode at 120 o C with optimization on

21 cut-off voltage. (E) Stable galvanostatic cycling of GF-HC (10 A g -1 ) over 45,000 cycles at 100 o C. fig. S16. Charge/discharge curves of the GF-HC cathode and ionic conductivity of [EMIm]AlxCly ionic liquid electrolyte at low temperature. (A-D) Charge/discharge curves of GF-HC cathode at different rates at (A) 0 o C, (B) -10 o C, (C) -20 o C, and (D) - 30 o C. (E) Relative ionic conductivity of [EMIm]AlxCly ionic liquid electrolyte at different low temperature below 0 o C, comparing to that at 25 o C (15 ms cm -1 ).

22 fig. S17. Comparison of electrochemical performances of GF-HC and GF-p cathodes at low temperature. (A) Capacity retention of GF-p cathode (compared with 95 mah g -1 at 25 o C) at different low temperature and different current densities. (B) Capacity retention of GF-HC cathode (compared with 120 mah g -1 at 25 o C) at different low temperatures and different current densities.

23 fig. S18. Photograph of flexible Al-GB. The flexible Al-GB can power LED light under (A) 0 o, (B) 90 o and (C) 180 o bending. (D-F) The reverse side view (D) and top (E) side view of the flexible Al-GB watchband connecting to the LED watch. (F) The watchband battery can successfully power the LED watch while been wrapped around wrist. fig. S19. EIS spectra of flexible Al-GB soft pack cell after different bending cycles.

fig. S20. Additional information on coin cell fabrication, demonstration for the absence of side reaction, and the electrochemical performance based on mass loading.

24 fig. S20. Additional information on coin cell fabrication, demonstration for the absence of side reaction, and the electrochemical performance based on mass loading. (A) Model of fabricated coin cell, the electrolyte cannot touch the cathode shell, so that suspected stainless steel-involved side reaction cannot happen. (B) The CV spectra of Al-ion coin cell with graphene cathode, nickel foil current collector without graphene cathode, and tantalum current collector without graphene cathode. Inset shows the magnified CV spectra of nickel foil current collector without graphene cathode, and tantalum current collector without graphene cathode. The extremely low cathodic peak currents of current collectors suggest negligible side reaction within those voltage range, demonstrating the stability of Ni and Ta current collectors within this voltage range. The

25 very weak anodic peak is due to electrolyte decomposition. (C) Photograph of coin cell shell after 200,000 cycles, exhibiting no sign of corruption at all. Together with element mapping result in fig. S13 that no sign of dissoluted Fe, Cr and Ni specie was detected, the absence of side reaction caused by stainless steel coin cell shell or nickel current collector is confirmed. (D) Specific capacity of GF-HC cathode at different active material areal loading (current density of 1 A g -1 ). (E) SEM image of fresh nickel foil current collector before being cycling. (F) SEM image of nickel foil current collector after 50,000 cycles, exhibiting no difference with nickel foil before being cycling.

26 fig. S21. Galvanostatic cycling of the GF-HC cathode with [Et3NH]AlxCly electrolyte. (A) Stable cycling of GF-HC cathode at 5 A g -1 within 11,000 cycles. (B) Corresponding charge and discharge curves within different cycles. (C) Rate performance of different cathode (GF-HC, GF-p and graphene foam) with [Et3NH]AlxCly electrolyte, demonstrating much better performance of GF-HC cathode than GF-p and graphene foam. (D) EIS spectra of different Al-GB with different cathodes and [Et3NH]AlxCly electrolyte. These results demonstrate that the advance in electrochemical performaces of GF-HC mainly owes to the "3H3C" design of cathode material rather than electrolyte. Details on this new electrolyte will be reported later.

27 Table S1. Electrochemical properties of electrode materials from various reports. Electrode Rate capability Cycle life Highest Capacity current retention Capacity Ref. Cycle number density at highest retention (A g -1 ) current Al-ion battery (AIB) Sodium-ion battery Lithium-ion battery (LIB) Supercapacitor (SC) This work % % Graphene foam Porous 3D Foam % % (2) 8 75% % (7) Graphitic foam 6 83% % (1) Graphite % % (8) NVP % % (33) NVP 11 70% % (15) Bimuth 2 90% % (34) Phosphor % % (35) Carbon 20 31% % (36) TiO % % (37) LTO 35 45% % (38) FeS 10 59% % (39) Silicon % (40) Silicon 10 40% % (41) Sulfur % % (42) Sulfur 8 40% % (43) Sulfur % (44) Sulfur % (45) LFP 81 15% % (46) Graphene % % (16) Graphene % % (47) Graphene 40 70% % (4) LDH % % (48)

Supplementary Figures

Supplementary Figures Supplementary Figure 1: Microstructure, morphology and chemical composition of the carbon microspheres: (a) A SEM image of the CM-NFs; and EDS spectra of CM-NFs (b), CM-Ns (d) and