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Low cost, low defect and high-quality graphene have been produced in three simple exfoliation steps as a fully tested commercial concept. Low energy thermal arc-discharging expands the electrolytic graphite rod electrodes into hierarchical-like 3D graphene retaining the graphite structural order on a basal plane and chemical purity. Multi-size ball milling causes movement of the graphene materials in multi-shear directions, with optimized speed of the balls and lesser time. Micro-waving further separates the graphene sheets by “thermal expansion and release” mechanism utilizing thermally induced lattice vibrations. This also causes higher lattice order on basal plane improving directional and surface properties. The produced graphene (XRD 2theta = 26 degrees) has low defect (I(D)/I(G) between 0.05 and 0.2), retains chemical purity (between 0.56 and 2.4% change in oxygen content), and with comparatively optimized effective nano-sizes (ranging from 300nm to 35um). These properties make the graphene suitable for diverse applications, dispersibility in various solvents, conformability to flat semitransparent surfaces, and storable in concentrated slurries (>50 mg mL−1) or powder. Keywords: Low Defect; 2D Planar; Arc Discharge Graphene; PPC Sonication; 5 Sec Microwaving; Exfoliation; Electronics. References O.J. Dada, " In-Situ Electrochemical Functionalization of Reduced Graphene Oxide: Positive Lead Acid Case. " ECS Trans., vol. 66, no. 14, pp. 19–30, Aug. 2015. O.J. Dada, “ In-Situ Electrochemical Functionalization of Reduced Graphene Oxide: Positive Lead Acid Case.,” ECS Abstract., MA2015-01 (870), April 2015. O.J. Dada and D. Villaroman, " Superior Electronic and Dielectric Properties of Corrugated ElectrochemicallyReduced Graphene over Graphene Oxide Papers " Journal of the Electrochemical Society, vol 166 no.2, pp D1-D16, 2019. O.J. Dada, " Functional Cathodic and Anodic Transition of Graphene Oxide Paper in Lead Acid Battery System and Its Electrochemistry ". Materials Today: Proceedings”, vol. 3, no. 8, 2688-2697, 2016. O.J. Dada, " Interconnected Graphene Networks as Novel NanoComposite for Optimizing Lead Acid Cathode ". IEEE NANO 2015- Int. Conf. Nanotechnology, Rome, 2015. O.J. Dada, " Higher Capacity Utilization and Rate Performance of Lead Acid Battery Electrodes Using Graphene Additives ”. Journal of Energy Storage, vol. 23, pp579-589, Jun. 2019. O.J. Dada, " Effect of the Size and Conductivity of Tailored Graphene Electro-Catalysts, Lead Acid Battery Cathode as a Case ". IEEE NANO 2015- Int. Conf. Nanotechnology, Rome, Italy, 2015. O.J. Dada, " Wrinkled Graphene Oxide Synthesis by Electrolytic Arc Discharge of Graphite Rods and Slightly Modified Hummer’s Process ". Available at SSRN 3368351, 2019. O.J. Dada, " Highly Ordered Commercial Graphene Manufactured from 3 Simple Steps ". Available at SSRN 3335369, 2019. O.J. Dada, " Low Defect Planar Graphene Exfoliation by Sonication in Polypropylene Carbonate and 5 sec Microwaving ". Available at SSRN 3386581, 2019. O.J. Dada, " Utilization of Hard Carbon as a Substitute for Graphite As Efficient Lithium Battery Anode Material ". Available at SSRN 3368403, 2019. O.J. Dada, “ High Performance Lithium Battery Anodes from Non-Water based Graphene ”. Available at SSRN 3368433, 2019. O.J. Dada, “ Free Standing Porous Graphene and Reduced Graphene Papers Manufactured from Sedimentation of Arc Discharge of Graphite Rods ”. Available at SSRN 3481786, 2019. O.J. Dada, " Corrigendum to “Higher capacity utilization and rate performance of lead acid battery electrodes using graphene additives” . Journal of Energy Storage, vol. 23, pp579–589, Jun. 2019.

Free Standing Porous Graphene and Reduced Graphene Papers manufactured from Sedimentation of Arc Discharge of Graphite Rods. At SignEcoTech, novel and newer nano-carbons such as hard carbons, homogenized graphene, low defect highly crystalline graphene’s, and wrinkled graphene [1-14]. Here, Graphene Oxide papers have been synthesized previously by flow-directed assembly, where the pressure of air within the assembly supports graphene oxide sheets in their nano-crystalline colloidal solution being filtered on nano-porous filter paper. However in this research, we haven’t used any filter paper, or directed flow assembly, but sedimentation of the colloidal solution in ethyl alcohol in a dish. Then, the wrinkled the hierarchical GO sheets fall under gravity by sedimentation. Wrinkling in GO was enhanced by low defects, multi-layer clusters, and variegated + edge interaction amongst graphene clusters, as such the sedimented graphene papers were porous, intertwined and free standing. The composition of GO was confirmed by XPS, while the low defect level clearly marked by higher planar order and low ID/IG band. The wrinkled, multilayer clusters and carbonic surface properties of the graphene oxide sheets enhanced fast sedimentation, evaporation of the alcohol and formation of porous GO structure. The porous reduced\GO morphology is captured by optical microscope. Keywords: Wrinkled GO Papers, Reduced Graphene, Arc Discharge, Modified Hummers Method

Technological demands in HEVs, renewable systems, and electrical storage systems coupled with its mature industrial process, recyclability and low cost has furthered the interests in Lead acid (LAB) systems. The LAB Positive active materials, due to low utilization and life cycle, severely limits the competitiveness of the traditional battery. Reported attempts to optimize the lead acid system using nano-size materials including graphene and carbon nanotubes, has yielded increase in some performance metrics, but little is known about the responsible mechanisms 1,2 3. Based on the gel-crystal theory, Pavlov et al. 4–6has established that the lead acid active mass particles comprises interfaces made of intermediate amorphous molecules, within which the electrochemical reactions take place. Little or nothing is known about the effects of additives of micro- and sub-micro sizes on the redox activity in the gel zone, and how the chemistry of the active mass is improved to result in global increase in capacity and cycle life of the positive active mass. This research demonstrates highly improved discharge capacity and cycle life obtained from careful combination of cathode materials with tailored graphene based additives: Graphene Oxide (GO), chemically converted graphene (CCG) and pristine graphene (GX). The chemical and electrochemical phenomena responsible for the high activity of the positive active particles in the cathode were established. PbO-GO had the best performance with highest utilization of 41.8%, followed by PbO-CCG (37.7%), PbO-control (29.7%), and PbO-GX (28.7%) at 2.5C rate. PbO-CCG seemed to have the best performance: better on charging, lower internal resistance, but poorer cycle life compared to PbO-GO. GO & CCG optimized samples had better discharge capacity and cyclic performance. Cycled at 2.5C rate, all samples but the control, had Increasing capacity till after ~50 cycles. This is due to electro-functionalization of the graphene sheets which tailored the growth of PbO2crystals in the gel zone. Also, there is a difference in the response of graphene composites to the chemistry of the reacting species on charging and discharging. The extra-ordinary mobility of ions was facilitated by electrochemical functionalization7and controlled nano-recrystallization of cathode particles along graphene sheets embedded with the gel-crystal interface. Porosity or surface area increase had no effects. REFERENCES 1. Xiang, J. et al. Beneficial effects of activated carbon additives on the performance of negative lead-acid battery electrode for high-rate partial-state-of-charge operation. J. Power Sources 241,150–158 (2013). 2. Wang, H., Yu, J., Zhao, Y. & Guo, Q. A facile route for PbO@C nanocomposites: An electrode candidate for lead-acid batteries with enhanced capacitance. J. Power Sources 224,125–131 (2013). 3. Yolshina, L. A., Yolshina, V. A., Yolshin, A. N. & Plaksin, S. V. Novel lead-graphene and lead-graphite metallic composite materials for possible applications as positive electrode grid in lead-acid battery. J. Power Sources 278,87–97 (2015). 4. Pavlov, D. & Balkanov, I. Hydration and Amorphization of Active Mass Pb02 Particles and Their Influence on the Electrical Properties of the Lead-Acid Battery Positive Plate. 136,(2003). 5. Pavlov, D. & Petkova, G. Phenomena That Limit the Capacity of the Positive Lead Acid Battery Plates. J. Electrochem. Soc. 149,A654 (2002). 6. Pavlov, D. The Lead-Acid Battery Lead Dioxide Active Mass: A Gel-Crystal System with Proton and Electron Conductivity. J. Electrochem. Soc. 139,3075 (1992). 7. Dada, O. In-Situ Electrochemical Functionalization of Reduced Graphene Oxide: Positive Lead Acid Electrode Case. in 227th ECS Meeting (May 24-28, 2015). Controlled Nano-Crystallization for Optimizing of Lead Acid Positive Active Material Using Graphene Nano-Composites Technological demands in HEVs, renewable systems, and electrical storage systems coupled with its mature industrial process, recyclability and low cost has furthered the interests in Lead acid (LAB) systems. The LAB Positive active materials, due to low utilization and life cycle, severely limits the competitiveness of the traditional battery. Reported attempts to optimize the lead acid system using nano-size materials including graphene and carbon nanotubes, has yielded increase in some performance metrics, but little is known about the responsible mechanisms 1,2 3. Based on the gel-crystal theory, Pavlov et al. 4–6 has established that the lead acid active mass particles comprises interfaces made of intermediate amorphous molecules, within which the electrochemical reactions take place. Little or nothing is known about the effects of additives of micro- and sub-micro sizes on the redox activity in the gel zone, and how the chemistry of the active mass is improved to result in global increase in capacity and cycle life of the positive active mass. This research demonstrates highly improved discharge capacity and cycle life obtained from careful combination of cathode materials with tailored graphene based additives: Graphene Oxide (GO), chemically converted graphene (CCG) and pristine graphene (GX). The chemical and electrochemical phenomena responsible for the high activity of the positive active particles in the cathode were established. PbO-GO had the best performance with highest utilization of 41.8%, followed by PbO-CCG (37.7%), PbO-control (29.7%), and PbO-GX (28.7%) at 2.5C rate. PbO-CCG seemed to have the best performance: better on charging, lower internal resistance, but poorer cycle life compared to PbO-GO. GO & CCG optimized samples had better discharge capacity and cyclic performance. Cycled at 2.5C rate, all samples but the control, had Increasing capacity till after ~50 cycles. This is due to electro-functionalization of the graphene sheets which tailored the growth of PbO2 crystals in the gel zone. Also, there is a difference in the response of graphene composites to the chemistry of the reacting species on charging and discharging. The extra-ordinary mobility of ions was facilitated by electrochemical functionalization7 and controlled nano-recrystallization of cathode particles along graphene sheets embedded with the gel-crystal interface. Porosity or surface area increase had no effects. REFERENCES 1. Xiang, J. et al. Beneficial effects of activated carbon additives on the performance of negative lead-acid battery electrode for high-rate partial-state-of-charge operation. J. Power Sources 241, 150–158 (2013). 2. Wang, H., Yu, J., Zhao, Y. & Guo, Q. A facile route for PbO@C nanocomposites: An electrode candidate for lead-acid batteries with enhanced capacitance. J. Power Sources 224, 125–131 (2013). 3. Yolshina, L. A., Yolshina, V. A., Yolshin, A. N. & Plaksin, S. V. Novel lead-graphene and lead-graphite metallic composite materials for possible applications as positive electrode grid in lead-acid battery. J. Power Sources 278, 87–97 (2015). 4. Pavlov, D. & Balkanov, I. Hydration and Amorphization of Active Mass Pb02 Particles and Their Influence on the Electrical Properties of the Lead-Acid Battery Positive Plate. 136, (2003). 5. Pavlov, D. & Petkova, G. Phenomena That Limit the Capacity of the Positive Lead Acid Battery Plates. J. Electrochem. Soc. 149, A654 (2002). 6. Pavlov, D. The Lead-Acid Battery Lead Dioxide Active Mass: A Gel-Crystal System with Proton and Electron Conductivity. J. Electrochem. Soc. 139, 3075 (1992). 7. Dada, O. In-Situ Electrochemical Functionalization of Reduced Graphene Oxide: Positive Lead Acid Electrode Case. in 227th ECS Meeting (May 24-28, 2015).

Graphene based nano-sheets have gained prominence in batteries and super capacitors owing to their high aspect ratio, exceptional transport properties, ionic functionalities, and surface properties. Variants like pristine graphene, graphene oxide, or chemically/thermally reduced graphene are not equal in ionic and transport properties owing to the presence or grafting of functional groups in the honey comb carbon structure. To perform as an electro-catalyst, functionalization of graphene is done by ex-situ grafting desired ions and molecules, usually covalently and non-covalently. Graphene which has zero band gap, could be treated to create semi-conductor-type functionalities. Functionalization makes its surface more amenable to further processes like deposition and nucleation of guest molecules or ions. This work demonstrates the cathodic electro-functionalization of reduced graphene sheets in the presence of lead dioxide and sulphuric acid electrolyte. High resolution SEM and TEM morphology reveals the surface of graphene sheets have been altered with the atoms of Lead, Oxygen and Sulphur. The deconvoluted C 1s spectra of electrochemically functionalized graphene shows carbon types with chemical states appearing at 284.3 eV (graphite, C—C/C═C), 286.3 eV (C—OH), 287.4 eV (C═O), and 288.3 eV (O—C═O), and 290.5 which was ∏-∏ interaction. Compared to reduced graphene, the intensity of C-C peak reduced very much, and was sacrificed for the re-appearance of oxygen functional groups, especially the (O—C═O). Further investigation were done using Raman spectroscopy and FTIR. There was a marked decrease in I(D)/I(G) ratio with presence of a bond peak at 2642 and 2940 cm-1. However, FTIR reveals that the peaks for most functional groups were still minimized like the reduced graphene, while band showing vibrations of oxides and sulphates appear between 550-1100. There were significant differences in characteristic –OH vibrations between 3000-3700 cm-1, due to water of crystallization associated with gel-crystal interface. This work also determined that the hydroxyl functional groups and carboxyl functional groups were substituted electrochemically by Pb(OH)- on charging and HSO3 - ions during discharge in the hydrated gel interface of the positive lead dioxide plate. There were evidences of increased mobility of hydrogen/hydroxyl ions which is desirable, and more efficient for conduction of SO4 2- back into the electrolyte during discharge. Oxygen containing groups with its inherent functional properties aided the hydrolysis, combination of OH- and H+ and SO42- , which made up the hydrated zone which encapsulates the graphene nano-sheets. This optimized ionic conductivity was marked by ~27% increase in discharge capacity after few cycles, and ~38.5% increase respectively after 25 cycles. Progressive functionalization of the reduced sheets enabled the Pb(OH)+, HSO3 - ions decorations on reduced graphene, by substitution of OH- and other functional groups, and ∏-∏ bond interaction as prominent mechanisms. Increase in ionic activity aided the nucleation of intermediate active materials, and increase in active sites on the large surface area of the graphene nano-sheets. This resulted in increase in capacity and charge acceptance at 0.25C rate. In-situ electrochemical functionalization of reduced graphene nano-sheets in controlled ionic and conductive system will be a cutting edge approach for controlling it’s behavior in energy materials as an electro-catalyst, in a scalable and cost effective way.