{ "spore": "profile", "id": "graphite-anode", "spore_version": "0.2", "family": "lithium", "name": "Graphite", "abbreviation": "Gr", "role": "anode", "category": "energy", "type": "li-ion-anodes", "summary": "Graphite is the layered carbon that holds lithium between its sheets in most lithium-ion cells. It is also the anode material in the GS Yuasa lithium-ion cells chosen for the International Space Station batteries, according to NASA. It stores charge at a very low voltage, which is good for cell energy but means lithium can plate on it when it is charged fast or cold.\n", "best_for": "Mature, low-cost anode with high capacity per gram at a low lithiation voltage.", "weakest_at": "Fast or cold charging (lithium plating) and heating (its protective film starts to break down at about 90 to 120 C).", "identity": { "formula": "C", "cas": "7782-42-5", "designations": [], "source": "sds-aldrich-graphite", "where": "Section 3.1" }, "tags": { "environments": [ "low-earth-orbit" ], "stresses": [ "extreme-cold", "extreme-heat" ], "applications": [ "batteries" ] }, "properties": [ { "benchmark": "theoretical_capacity", "value": 372, "bound": "exact", "unit": "mAh/g", "scope": "material", "conditions": { "reaction": "graphite to LiC6, full lithiation", "stated_as": "approximately 372 mAh/g" }, "method": "Faraday calculation for one lithium per six carbon atoms (value as stated by the review)", "status": "calculated", "source": "frontiers-graphite-2026", "where": "Section 2", "source_detail": { "title": "Intrinsic structural design of graphite anodes for fast-charging lithium-ion batteries (Wu et al., Frontiers in Chemistry)", "id": "doi 10.3389/fchem.2026.1869263", "url": "https://doi.org/10.3389/fchem.2026.1869263", "year": 2026, "kind": "paper", "license": "CC BY" } }, { "benchmark": "volume_change", "value": 10, "bound": "exact", "unit": "%", "scope": "material", "conditions": { "event": "lithiation of graphite", "stated_as": "around 10%" }, "method": "Statement in a review of electrochemical dilatometry (operando electrode thickness measurement)", "status": "ground", "source": "escher-2022", "where": "Introduction", "source_detail": { "title": "A Practical Guide for Using Electrochemical Dilatometry as Operando Tool in Battery and Supercapacitor Research (Escher et al., Energy Technology)", "id": "doi 10.1002/ente.202101120", "url": "https://doi.org/10.1002/ente.202101120", "year": 2022, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "interlayer_spacing", "label": "Layer spacing, pristine graphite", "value": 0.335, "bound": "exact", "unit": "nm", "scope": "material", "conditions": { "state": "commercial graphite, uncharged", "stated_as": "approximately 0.335 nm" }, "method": "Structural value quoted in a review", "status": "ground", "source": "frontiers-graphite-2026", "where": "Section 3.1", "source_detail": { "title": "Intrinsic structural design of graphite anodes for fast-charging lithium-ion batteries (Wu et al., Frontiers in Chemistry)", "id": "doi 10.3389/fchem.2026.1869263", "url": "https://doi.org/10.3389/fchem.2026.1869263", "year": 2026, "kind": "paper", "license": "CC BY" } }, { "benchmark": "interlayer_spacing", "label": "Layer spacing, fully lithiated LiC6", "value": 0.37, "bound": "exact", "unit": "nm", "scope": "material", "conditions": { "state": "fully lithiated LiC6", "stated_as": "approximately 0.370 nm" }, "method": "Structural value quoted in a review", "status": "ground", "source": "frontiers-graphite-2026", "where": "Section 3.1", "source_detail": { "title": "Intrinsic structural design of graphite anodes for fast-charging lithium-ion batteries (Wu et al., Frontiers in Chemistry)", "id": "doi 10.3389/fchem.2026.1869263", "url": "https://doi.org/10.3389/fchem.2026.1869263", "year": 2026, "kind": "paper", "license": "CC BY" } }, { "benchmark": "thermal_runaway_onset", "label": "Heat-release onset of carbon or graphite anodes", "value": 80, "value_high": 160, "bound": "range", "unit": "°C", "scope": "material", "conditions": { "depends_on": "lithiation state, electrolyte composition, aging history", "note": "reported range, not a single threshold" }, "method": "Literature summary of calorimetry results in a review", "status": "ground", "source": "advsci-failure-2026", "where": "Section 3.1", "source_detail": { "title": "A Review of Failure Modes and Safety Strategies of Lithium-Ion Batteries from Materials to Systems (Yang et al.)", "id": "doi 10.1002/advs.76228", "url": "https://doi.org/10.1002/advs.76228", "year": 2026, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "density", "label": "Specific gravity of graphite (carbon record)", "value": 1.9, "value_high": 2.3, "bound": "range", "unit": "g/cm3", "scope": "material", "conditions": { "form": "graphite, general reference value for the element carbon", "note": "not battery-grade electrode density" }, "method": "Reference value quoted in the PubChem carbon record", "status": "ground", "source": "pubchem-carbon", "where": "Other Experimental Properties (specific gravity)", "source_detail": { "title": "PubChem compound summary, Carbon (CID 5462310), GHS classification", "id": "CID 5462310", "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5462310", "year": 2026, "kind": "database" } }, { "benchmark": "thermal_runaway_onset", "label": "DSC onset, fully lithiated graphite with electrolyte", "value": 100, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "material": "fully lithiated graphite", "test": "differential scanning calorimetry, comparison value given in an LTO paper", "test_conditions_for_graphite": "not given in the abstract" }, "method": "DSC", "status": "ground", "note": "Total heat for fully lithiated graphite was given as 2700 J/g (unit printed as \"Jg\" on the page, read as J/g).", "source": "belharouak-2007", "where": "Abstract", "source_detail": { "title": "On the safety of the Li4Ti5O12/LiMn2O4 lithium-ion battery system (Belharouak, Sun, Lu, Amine; J. Electrochem. Soc. 154(12) A1083-A1087), abstract page at Oak Ridge National Laboratory", "id": "doi 10.1149/1.2783770", "url": "https://doi.org/10.1149/1.2783770", "year": 2007, "kind": "paper" } }, { "benchmark": "sei_decomposition_onset", "label": "SEI exothermic decomposition temperature range", "value": 90, "value_high": 120, "bound": "range", "unit": "°C", "scope": "material", "conditions": { "layer": "solid electrolyte interphase on the anode", "gases": "CO2, H2, CH4 and in some cases HF" }, "method": "Literature statement in a review", "status": "ground", "source": "advsci-failure-2026", "where": "Section 3.2.1", "source_detail": { "title": "A Review of Failure Modes and Safety Strategies of Lithium-Ion Batteries from Materials to Systems (Yang et al.)", "id": "doi 10.1002/advs.76228", "url": "https://doi.org/10.1002/advs.76228", "year": 2026, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "capacity_before_zero_volts", "label": "Capacity reached before graphite potential falls to 0 V vs Li/Li+ (-20 C)", "value": 412, "bound": "exact", "unit": "mAh/g", "scope": "material", "conditions": { "temperature_C": -20, "current": "0.1 mA/cm2 (about C/24)", "cell": "three-electrode Li/graphite, 1 M LiPF6 in EC/DMC/DEC 1:1:1", "formation_cycling": "none" }, "method": "Constant-current charge with a lithium reference electrode", "status": "ground", "note": "At 20 C and the same current, staging plateaus gave near-theoretical capacity (372 mAh/g). Reaching 0 V early means lithium plating starts before the graphite is full.", "source": "chen-2025", "where": "Results on variable-temperature charging, Figure 3", "source_detail": { "title": "Mechanistic Understanding of Lithium-Ion Adsorption, Intercalation, and Plating during Charging of Graphite Electrodes (Chen et al., ACS Electrochemistry)", "id": "doi 10.1021/acselectrochem.4c00079", "url": "https://doi.org/10.1021/acselectrochem.4c00079", "year": 2025, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "capacity_before_zero_volts", "label": "Capacity reached before graphite potential falls to 0 V vs Li/Li+ (-30 C)", "value": 160, "bound": "exact", "unit": "mAh/g", "scope": "material", "conditions": { "temperature_C": -30, "current": "0.1 mA/cm2 (about C/24)", "cell": "three-electrode Li/graphite, 1 M LiPF6 in EC/DMC/DEC 1:1:1", "formation_cycling": "none" }, "method": "Constant-current charge with a lithium reference electrode", "status": "ground", "source": "chen-2025", "where": "Results on variable-temperature charging, Figure 3", "source_detail": { "title": "Mechanistic Understanding of Lithium-Ion Adsorption, Intercalation, and Plating during Charging of Graphite Electrodes (Chen et al., ACS Electrochemistry)", "id": "doi 10.1021/acselectrochem.4c00079", "url": "https://doi.org/10.1021/acselectrochem.4c00079", "year": 2025, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "capacity_before_zero_volts", "label": "Capacity reached before graphite potential falls to 0 V vs Li/Li+ (-40 C)", "value": 106, "bound": "exact", "unit": "mAh/g", "scope": "material", "conditions": { "temperature_C": -40, "current": "0.1 mA/cm2 (about C/24)", "cell": "three-electrode Li/graphite, 1 M LiPF6 in EC/DMC/DEC 1:1:1", "formation_cycling": "none" }, "method": "Constant-current charge with a lithium reference electrode", "status": "ground", "source": "chen-2025", "where": "Results on variable-temperature charging, Figure 3", "source_detail": { "title": "Mechanistic Understanding of Lithium-Ion Adsorption, Intercalation, and Plating during Charging of Graphite Electrodes (Chen et al., ACS Electrochemistry)", "id": "doi 10.1021/acselectrochem.4c00079", "url": "https://doi.org/10.1021/acselectrochem.4c00079", "year": 2025, "kind": "paper", "license": "CC BY 4.0" } }, { "benchmark": "cell_specific_energy", "label": "Specific energy of the ISS LSE134-101 cell (graphite anode, lithium cobalt oxide cathode)", "value": 155, "bound": "exact", "unit": "Wh/kg", "scope": "cell", "conditions": { "cell": "GS Yuasa LSE134-101, 134 A-hr nameplate", "state": "beginning of life" }, "method": "Nameplate data in a NASA battery workshop presentation", "status": "ground", "note": "The slide gives 155 Wh/kg, but its own nameplate energy of 496 Wh and cell mass of 3.53 kg work out to about 140.5 Wh/kg, so the slide is internally inconsistent.", "source": "nasa-iss-graika-2017", "where": "Slide \"Cell Information\"", "source_detail": { "title": "Assessment of International Space Station (ISS) Lithium-ion Battery Thermal Runaway (Graika)", "id": "NTRS 20170003873", "url": "https://ntrs.nasa.gov/citations/20170003873", "year": 2017, "kind": "report", "license": "public domain" } }, { "benchmark": "charge_temperature_range", "label": "Allowed charge temperature of the ISS LSE134-101 cell", "value": 10, "value_high": 35, "bound": "range", "unit": "°C", "scope": "cell", "conditions": { "cell": "GS Yuasa LSE134-101", "discharge_range": "-10 to +35 C" }, "method": "Temperature range listed on the cell information slide", "status": "ground", "note": "The slide gives the range, not the reason for the lower charge limit.", "source": "nasa-iss-graika-2017", "where": "Slide \"Cell Information\"", "source_detail": { "title": "Assessment of International Space Station (ISS) Lithium-ion Battery Thermal Runaway (Graika)", "id": "NTRS 20170003873", "url": "https://ntrs.nasa.gov/citations/20170003873", "year": 2017, "kind": "report", "license": "public domain" } } ], "corrosion": [ { "environment": "Carbonate electrolyte during first charge (SEI formation)", "headline": "On the first charge the electrolyte forms a protective film on the graphite, which can later crack and reform.", "effect": "Electrolyte is reduced on the graphite surface and forms a protective film (SEI) made of an inner inorganic layer (Li2CO3, LiF, Li2O) and an outer organic layer (ROCO2Li, ROLi). It protects the graphite, but it is not static: it can decompose, crack and reform during cycling or heating.\n", "rating": "unknown", "conditions": { "voltage": "forms below about 1 V vs Li/Li+", "electrolyte": "carbonate solvents with LiPF6" }, "source": "advsci-failure-2026", "where": "Section 3.2.1 and Section 4.2.1" }, { "environment": "Cracked SEI on lithiated graphite", "headline": "A cracked film lets electrolyte reach lithiated graphite, which damages the surface and speeds heat generation.", "effect": "Cracks let electrolyte reach lithiated graphite, which can cause solvent co-intercalation, graphite exfoliation and further surface damage, and speeds up heat generation.\n", "rating": "unknown", "conditions": { "trigger": "repeated cycling or thermal exposure" }, "source": "advsci-failure-2026", "where": "Section 4.2.1" }, { "environment": "Propylene carbonate electrolyte", "headline": "Propylene carbonate enters the graphite layers along with lithium, a damaging side reaction.", "effect": "Propylene carbonate co-intercalates into the graphite lattice along with lithium ions, a side reaction that dilatometry can detect.", "rating": "unknown", "conditions": { "electrolyte": "propylene carbonate based" }, "source": "escher-2022", "where": "Section 2.3" }, { "environment": "Copper current collector (anode side) during over-discharge", "headline": "Over-discharge dissolves the copper current collector, which can cause short circuits and capacity loss.", "effect": "Copper anode current collectors dissolve under over-discharge, which can cause contact loss, short circuits and capacity loss.", "rating": "unknown", "conditions": { "trigger": "over-discharge", "general_statement": "for Li-ion batteries, not graphite specific" }, "source": "nanomicro-corrosion-2026", "where": "Section on electrochemical corrosion in batteries" }, { "environment": "Heated electrolyte-wet lithiated graphite", "headline": "Once the film breaks down, heated lithiated graphite reacts strongly with the electrolyte.", "effect": "After the SEI breaks down, the exposed lithiated graphite reacts strongly and exothermically with carbonate solvents (EC, DMC, DEC), producing CO2, CH4 and other light hydrocarbons. This is the first major heat-release step in thermal runaway.\n", "rating": "unknown", "conditions": { "temperature": "starts in the 50 to 160 C initiation window of thermal runaway" }, "source": "advsci-failure-2026", "where": "Section 3.1 and Section 3.2.2" } ], "risks": { "hazards": [ { "text": "PubChem aggregates 2727 reports from 27 notifications for the entry \"Carbon\" (includes graphite, CAS 7782-42-5): 55.1% report H319 and 51.1% report H335, while 40.2% (1095 reports) say the substance does not meet GHS hazard criteria. Classification depends on the supplier and grade.\n", "ghs": [ "H319", "H335" ], "source": "pubchem-carbon", "where": "Safety and Hazards, GHS Classification" }, { "text": "Sigma-Aldrich SDS for graphite (product 496596) classifies it as not a hazardous substance or mixture, and notes that further processing of solids may form combustible dusts. Listed workplace limits include NIOSH REL TWA 2.5 mg/m3 and ACGIH TLV TWA 2 mg/m3.\n", "ghs": [], "source": "sds-aldrich-graphite", "where": "Sections 2, 7.1 and 8.1" }, { "text": "SGL Technic SDS for a graphite powder product states that graphite dust of 4 to 40 micrometre particle size can explode over a wide range of concentrations, was classified St1, and that graphite dusts could cause an electrical short. The SDS also warns of slipping on spilled powder.\n", "ghs": [], "source": "sds-sgl-graphite", "where": "Sections 2, 9 and 10" } ], "failure_risks": [ { "mode": "Lithium plating", "trigger": "Fast charging or low temperature polarizes the graphite so its surface potential falls to or below 0 V vs Li/Li+.", "consequence": "Loss of active lithium, capacity fade and potential safety risks.", "severity": "high", "source": "frontiers-graphite-2026", "where": "Section 2" }, { "mode": "Cold charging cannot fill the graphite", "trigger": "Charging a Li/graphite cell below -20 C", "consequence": "At -30 C and -40 C the graphite potential crossed 0 V vs Li/Li+ after only 160 and 106 mAh/g, against 412 mAh/g at -20 C, so lithium intercalation drops sharply and competes with plating.", "severity": "high", "source": "chen-2025", "where": "Abstract and Results, Figure 3" }, { "mode": "SEI decomposition starting thermal runaway", "trigger": "Heating of a charged cell, typically at high state of charge", "consequence": "Exothermic SEI breakdown at 90 to 120 C releases CO2, H2, CH4 and sometimes HF, then lithiated graphite reacts with the electrolyte.", "severity": "high", "source": "advsci-failure-2026", "where": "Section 3.2" } ], "side_effects": [ { "text": "Gases from SEI decomposition (CO2, H2, CH4, sometimes HF) raise pressure inside the cell.", "affects": "Cell casing and neighbouring cells in a battery", "source": "advsci-failure-2026", "where": "Section 3.2.1" }, { "text": "Conductive graphite dust can cause an electrical short.", "affects": "Electronics near graphite powder handling", "source": "sds-sgl-graphite", "where": "Section 2" } ], "handling": [ { "text": "Keep the container tightly closed in a dry place. Avoid dust formation and provide exhaust ventilation where dust forms.", "source": "sds-aldrich-graphite", "where": "Sections 6.1, 7.1 and 7.2" } ], "mitigations": [ { "text": "Stabilize the SEI with surface coating, an artificial interphase or surface chemistry control, so that SEI breakdown and heat release are delayed.", "source": "advsci-failure-2026", "where": "Section 4.2.4" }, { "text": "Shorten lithium diffusion paths in the graphite (layer spacing, pores, particle size and morphology, edge sites) to lower polarization and plating tendency, at some cost in first-cycle efficiency and compaction density.", "source": "frontiers-graphite-2026", "where": "Sections 1 and 3" }, { "text": "ISS lithium-ion battery safeguards: two independent controls against thermal runaway, voltage and temperature monitoring of all 30 cells, cell-level fault isolation, radiant heat barriers between cell pairs, and vented gas directed away from neighbours.\n", "source": "nasa-iss-dalton-2016", "where": "Pages 10 to 13" } ] }, "uses": [ { "application": "batteries", "device": "ISS main lithium-ion battery cells", "example": "GS Yuasa 134 A-hr cells described by NASA as lithium cobalt oxide / carbon graphite, in 24 lithium-ion units planned to replace 48 nickel-hydrogen units on the International Space Station, 30 cells per battery.\n", "source": "nasa-iss-dalton-2016", "where": "Page 9 (cell down-select); battery count from nasa-iss-graika-2017 ORU slide" }, { "application": "batteries", "device": "Lithium-ion anode in electric-vehicle batteries", "example": "Wikipedia states that graphite is the predominant anode material in lithium-ion batteries and that the anode in virtually all EV batteries is graphite.", "source": "wiki-graphite", "where": "Battery section" }, { "application": "mechanisms", "device": "Brake linings, lubricants and powdered metals", "example": "USGS says natural graphite was widely used in batteries, brake linings, lubricants, powdered metals, refractory applications and steelmaking, with US consumption estimated at 71,000 tons in 2025.", "source": "usgs-graphite-2026", "where": "Domestic Production and Use (first paragraph)" } ], "supply": [ { "subject": "Natural graphite", "abundance": "World mine production 1,800,000 t in 2025 (estimate, rounded), world reserves 310,000,000 t, resources above 800 million tons of recoverable graphite outside the US. Country figures for 2025e: China 1,400,000 t; Madagascar 80,000 t; Tanzania 75,000 t; Brazil 65,000 t; Mozambique 60,000 t; Russia 25,000 t; India 17,000 t. USGS states China produced an estimated 82% of world natural graphite in 2025, mostly crystalline flake.\n", "producers": [ { "country": "China", "share_percent": 82, "year": 2025 } ], "critical_lists": [], "recycling": "USGS: graphite is recycled mainly from refractory brick and linings, and the abundance of graphite in the world market inhibits more recycling; quantity of recycled graphite was not available.\n", "substitutes": [ "Synthetic graphite powder and secondary synthetic graphite from machining graphite shapes compete for battery use" ], "source": "usgs-graphite-2026", "where": "Graphite (Natural), World Mine Production and Reserves; Events, Trends, and Issues; Substitutes" }, { "subject": "Graphite battery anode material (natural and synthetic), US trade", "abundance": "US imports of graphite battery anode material in the first 8 months of 2025 were 43,400 tons (28,100 tons in the same period of 2024); leading sources China 55%, Indonesia 31%, Republic of Korea 14%. Preliminary US antidumping duties on Chinese anode material were 93.50%, countervailing duties 11.58% to 721.03%. China exported 37,400 tons of spherical purified graphite in the first 9 months of 2025.\n", "producers": [], "critical_lists": [], "recycling": "Not stated for anode material in the source.", "substitutes": [], "source": "usgs-graphite-2026", "where": "Events, Trends, and Issues" } ], "media": [ { "file": "/media/lithium/graphite-anode-1.jpg", "caption": "Ball-and-stick model of the layered crystal structure of graphite.", "shows": "Three stacked sheets of carbon atoms in a physical model; lithium ions go between such sheets when a cell charges.", "conditions": "Photograph of a physical model, not a micrograph", "alt": "Photograph of a model of graphite: three flat layers of black spheres held apart by thin rods.", "credit": "MartinThoma (Wikimedia Commons)", "license": "CC0 1.0", "license_url": "https://creativecommons.org/publicdomain/zero/1.0/", "source_url": "https://commons.wikimedia.org/wiki/File:Graphite-crystal-structure.jpg" }, { "file": "/media/lithium/graphite-anode-2.jpg", "caption": "Scheme of a lithium-ion cell with a lithium cobalt oxide cathode and a graphite anode.", "shows": "Uncharged cell, charging (lithium ions leave LiCoO2 and enter graphite as LiC6) and discharging, with the cell equations.", "conditions": "Schematic drawing", "alt": "Four box diagrams of a battery cell: uncharged, charging, charged and discharging, with red lithium ions moving to a blue carbon electrode and the reaction 6C + Li+ + e- gives LiC6.", "credit": "Sergey WereWolf (Wikimedia Commons)", "license": "CC0 1.0", "license_url": "https://creativecommons.org/publicdomain/zero/1.0/", "source_url": "https://commons.wikimedia.org/wiki/File:Lithium_cobaltate_vs_graphite_lithium-ion_battery_scheme.png" }, { "file": "/media/lithium/graphite-anode-3.jpg", "caption": "Natural flake graphite, 32 mesh, 99% purity.", "shows": "Loose silvery-black flakes of natural graphite in a bag, the raw form that is milled and rounded for battery anodes.", "conditions": "Photograph; mesh size and purity as given on the Commons file page", "alt": "Close-up photograph of a pile of small shiny grey graphite flakes.", "credit": "2x910 (Wikimedia Commons)", "license": "CC BY-SA 4.0", "license_url": "https://creativecommons.org/licenses/by-sa/4.0/", "source_url": "https://commons.wikimedia.org/wiki/File:Flake_graphite.png" } ], "documents": [ { "title": "Sigma-Aldrich safety data sheet, graphite 496596 (revision 2015)", "type": "sds", "url": "https://www.physics.purdue.edu/primelab/safety/MSDS/SDS/graphite%20%20-%20Aldrich.pdf", "year": 2015 }, { "title": "SGL Technic safety data sheet, graphite microballoons (revision 2020)", "type": "sds", "url": "https://docs.gato.txst.edu/139064/Graphitized%20Microballoons.pdf", "year": 2020 }, { "title": "PubChem record for Carbon (GHS summary)", "type": "database", "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5462310" }, { "title": "USGS Mineral Commodity Summaries 2026, Graphite (Natural)", "type": "report", "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf", "year": 2026 }, { "title": "A Review of Failure Modes and Safety Strategies of Lithium-Ion Batteries from Materials to Systems", "type": "paper", "url": "https://doi.org/10.1002/advs.76228", "year": 2026 }, { "title": "NASA: International Space Station Lithium-Ion Battery (Dalton and Balcer)", "type": "report", "url": "https://ntrs.nasa.gov/citations/20160012048", "year": 2016 }, { "title": "Graphite (Wikipedia)", "type": "database", "url": "https://en.wikipedia.org/wiki/Graphite" } ], "gaps": [ "Crystal system and space group of graphite: no source opened yet.", "Average voltage vs Li/Li+: no source opened that states a figure.", "Electrode-grade density and electronic conductivity of graphite: only a general specific gravity range sourced.", "Measured reversible capacity at a stated rate and voltage window: not yet sourced.", "Cycle life of graphite cells with test conditions: not yet sourced.", "Moisture / water reaction of graphite anodes: no sourced data.", "Graphite on the USGS or other critical minerals lists: not read in the sources opened.", "Synthetic graphite supply (producers, shares): the USGS chapter covers natural graphite only.", "Flight results on graphite cell behaviour in vacuum, radiation or lunar cold: none found." ], "story": { "why": "Graphite is the layered carbon that holds lithium between its sheets in most lithium-ion cells. Lithium ions slot in between the carbon layers as the cell charges and leave as it discharges, so graphite serves as the anode, the negative electrode. NASA lists it as the anode material of the GS Yuasa lithium-ion cells chosen for the batteries of the International Space Station. It stores charge at a very low voltage, which is good for the energy of the cell, but that same low voltage means lithium metal can plate onto the surface when a cell is charged fast or cold.", "uses": [ { "where": "International Space Station main power", "line": "The GS Yuasa 134 Ah cells are described by NASA as lithium cobalt oxide with a carbon-graphite anode. Twenty-four lithium-ion units, with 30 cells per battery, were planned to replace 48 nickel-hydrogen units on the station." } ], "can_do": [ { "label": "Capacity", "line": "The theoretical specific capacity of 372 mAh/g follows from the reaction to LiC₆, which holds one lithium atom for every six carbon atoms.", "scope": "material", "value": "372 mAh/g" }, { "label": "Swelling", "line": "Graphite swells by around 10% on lithiation, and the spacing between its layers grows from about 0.335 nm when uncharged to about 0.370 nm when fully lithiated as LiC₆.", "scope": "material", "value": "About 10%" }, { "label": "Heat", "line": "The protective film on the anode, the solid electrolyte interphase, begins to decompose at about 90 to 120 °C and releases CO₂, H₂, CH₄ and sometimes HF. Reported onsets for thermal runaway of lithiated graphite range from 80 to 160 °C, depending on the lithiation state, electrolyte and aging. One comparison value gives 2,700 J/g of heat for fully lithiated graphite.", "scope": "material", "value": "Film breaks down at 90 to 120 °C" }, { "label": "Cold charging", "line": "In a three-electrode Li/graphite cell, at -30 °C and -40 °C the graphite potential crossed 0 V versus Li/Li⁺ after only 160 and 106 mAh/g, against 412 mAh/g at -20 °C. Once the potential reaches 0 V, lithium plating begins.", "scope": "material", "value": "106 mAh/g at -40 °C" }, { "label": "A flight cell", "line": "The GS Yuasa LSE134-101 cell with a 134 Ah nameplate is listed at 155 Wh/kg at beginning of life, and its charge temperature range is 10 to 35 °C. The slide's own nameplate energy and mass work out to about 140.5 Wh/kg.", "scope": "material", "value": "155 Wh/kg" } ], "compare": "Graphite is one of two anodes in this collection, and the other is lithium titanate. Graphite stores much more charge per gram (372 mAh/g, against a lower figure for lithium titanate that is not entered here) and operates at a very low voltage. Its weaknesses are fast or cold charging, where lithium plates, and heating, where its protective film breaks down at about 90 to 120 °C. The table compares graphite with the other anodes in the collection.", "compare_rows": [ { "label": "Density", "benchmark": "density", "scope": "material" }, { "label": "Theoretical capacity", "benchmark": "theoretical_capacity", "scope": "material" }, { "label": "Volume change", "benchmark": "volume_change", "scope": "material" } ], "handling": [], "good_for": [ "A mature, low-cost anode with high capacity per gram at a low lithiation voltage.", "Established in flight batteries, including the batteries of the International Space Station." ], "watch_out": [ "Fast or cold charging plates lithium metal on the surface, which loses active lithium and can be unsafe.", "The protective film breaks down at about 90 to 120 °C, and the exposed lithiated graphite then reacts strongly with the electrolyte.", "Graphite dust can explode in air and is electrically conductive, so it can short electronics." ], "verdict": "Graphite is the proven workhorse anode. It stores a lot of charge cheaply, and it needs protection from fast charging, cold charging and heat.", "recipe": { "line": "Graphite is pure carbon. Its atoms form flat sheets of six-sided rings, like a honeycomb, and the sheets stack on each other with weak bonds between them, leaving room for lithium to sit between the layers. Natural graphite comes from geologic deposits: it is mined, concentrated, then ground and sorted by flake size. Synthetic graphite is made by heating hydrocarbon materials to a very high temperature until they turn into graphite, a process called thermal graphitization, most often done in an Acheson furnace.", "parts": [ { "name": "Carbon", "symbol": "C", "role": "Forms the layered sheets. Lithium ions enter between the sheets when the cell charges and leave when it discharges." } ] }, "risk_groups": [ { "title": "For people", "lead": "Graphite is classified as not hazardous by some suppliers and as an irritant by others. The larger hazard is its dust.", "points": [ { "label": "Database entries", "line": "PubChem aggregates 2,727 reports from 27 notifications for the entry Carbon, which includes graphite. Of these, 55.1% report H319 (eye irritation) and 51.1% report H335 (respiratory irritation), while 40.2% say the substance does not meet GHS hazard criteria. Classification depends on the supplier and the grade." }, { "label": "A supplier sheet", "line": "A Sigma-Aldrich safety data sheet classifies graphite as not a hazardous substance or mixture, and notes that further processing of solids may form combustible dusts. Listed workplace limits include a NIOSH exposure limit of 2.5 mg/m³ and an ACGIH limit of 2 mg/m³, each averaged over a work shift." }, { "label": "Dust", "line": "An SGL Technic sheet states that graphite dust of 4 to 40 micrometre particle size can explode over a wide range of concentrations (class St1), that the dust can cause an electrical short, and that spilled powder is a slipping hazard." } ], "level": 1, "verdict": "Mostly not hazardous; dust can explode" }, { "title": "If a cell overheats", "lead": "These results come from laboratory studies and from reviews, not from incidents in the field.", "points": [ { "label": "The first step", "line": "Heating a charged cell breaks down the protective film at 90 to 120 °C. This releases CO₂, H₂, CH₄ and sometimes HF." }, { "label": "Then the graphite reacts", "line": "Once the film has broken down, the exposed lithiated graphite reacts strongly and exothermically with the carbonate solvents (EC, DMC and DEC), producing CO₂, CH₄ and other light hydrocarbons. This is the first major heat-release step in thermal runaway." }, { "label": "Pressure in the cell", "line": "The gases from the film breakdown raise the pressure inside the cell, which reaches the casing and neighbouring cells in a battery." }, { "label": "Lithium plating", "line": "Fast charging or low temperature polarizes the graphite so that its surface potential falls to or below 0 V versus Li/Li⁺. The result is loss of active lithium, capacity fade and potential safety risks." } ] }, { "title": "Handling and storage", "points": [ { "label": "Storage", "line": "Keep the container tightly closed in a dry place. Avoid dust formation and provide exhaust ventilation where dust forms." }, { "label": "Protecting the film", "line": "Surface coating, an artificial interphase or surface-chemistry control can stabilise the film and delay the breakdown and heat release." }, { "label": "Reducing plating", "line": "Shortening the paths lithium must diffuse through the graphite (layer spacing, pores, particle size and morphology, edge sites) lowers polarization and plating tendency, at some cost in first-cycle efficiency and compaction density." }, { "label": "Spacecraft protection", "line": "The ISS batteries use two independent controls against thermal runaway, voltage and temperature monitoring of all 30 cells, cell-level fault isolation, radiant heat barriers between cell pairs, and vented gas directed away from neighbours." } ] } ] }, "updated": "2026-10-16", "review": { "status": "draft", "method": "assistant", "checked_values": 13, "unreachable": 0, "caveats": 2, "note": "Re-read by an AI assistant on 2026-10-16: 13 of 13 benchmark values match their cited source; 0 could not be opened; 0 did not match." }, "sources": { "belharouak-2007": { "title": "On the safety of the Li4Ti5O12/LiMn2O4 lithium-ion battery system (Belharouak, Sun, Lu, Amine; J. Electrochem. Soc. 154(12) A1083-A1087), abstract page at Oak Ridge National Laboratory", "id": "doi 10.1149/1.2783770", "url": "https://doi.org/10.1149/1.2783770", "year": 2007, "kind": "paper" }, "usgs-graphite-2026": { "title": "Mineral Commodity Summaries 2026, Graphite (Natural)", "id": "USGS MCS 2026", "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf", "year": 2026, "kind": "report", "license": "public domain" }, "pubchem-carbon": { "title": "PubChem compound summary, Carbon (CID 5462310), GHS classification", "id": "CID 5462310", "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5462310", "year": 2026, "kind": "database" }, "sds-aldrich-graphite": { "title": "Sigma-Aldrich Safety Data Sheet, Graphite, product 496596, version 4.7", "id": "496596", "url": "https://www.physics.purdue.edu/primelab/safety/MSDS/SDS/graphite%20%20-%20Aldrich.pdf", "year": 2015, "kind": "datasheet" }, "sds-sgl-graphite": { "title": "SGL Technic Safety Data Sheet, Sigratherm Microballoons (hollow graphite microspheres)", "id": "OB_VAL1001008", "url": "https://docs.gato.txst.edu/139064/Graphitized%20Microballoons.pdf", "year": 2020, "kind": "datasheet" }, "nasa-iss-dalton-2016": { "title": "International Space Station Lithium-Ion Battery (Dalton, NASA Glenn; Balcer, Aerojet Rocketdyne)", "id": "NTRS 20160012048", "url": "https://ntrs.nasa.gov/citations/20160012048", "year": 2016, "kind": "report", "license": "public domain" }, "nasa-iss-graika-2017": { "title": "Assessment of International Space Station (ISS) Lithium-ion Battery Thermal Runaway (Graika)", "id": "NTRS 20170003873", "url": "https://ntrs.nasa.gov/citations/20170003873", "year": 2017, "kind": "report", "license": "public domain" }, "advsci-failure-2026": { "title": "A Review of Failure Modes and Safety Strategies of Lithium-Ion Batteries from Materials to Systems (Yang et al.)", "id": "doi 10.1002/advs.76228", "url": "https://doi.org/10.1002/advs.76228", "year": 2026, "kind": "paper", "license": "CC BY 4.0" }, "frontiers-graphite-2026": { "title": "Intrinsic structural design of graphite anodes for fast-charging lithium-ion batteries (Wu et al., Frontiers in Chemistry)", "id": "doi 10.3389/fchem.2026.1869263", "url": "https://doi.org/10.3389/fchem.2026.1869263", "year": 2026, "kind": "paper", "license": "CC BY" }, "chen-2025": { "title": "Mechanistic Understanding of Lithium-Ion Adsorption, Intercalation, and Plating during Charging of Graphite Electrodes (Chen et al., ACS Electrochemistry)", "id": "doi 10.1021/acselectrochem.4c00079", "url": "https://doi.org/10.1021/acselectrochem.4c00079", "year": 2025, "kind": "paper", "license": "CC BY 4.0" }, "escher-2022": { "title": "A Practical Guide for Using Electrochemical Dilatometry as Operando Tool in Battery and Supercapacitor Research (Escher et al., Energy Technology)", "id": "doi 10.1002/ente.202101120", "url": "https://doi.org/10.1002/ente.202101120", "year": 2022, "kind": "paper", "license": "CC BY 4.0" }, "nanomicro-corrosion-2026": { "title": "Electrochemical Corrosion and Safety Hazards in Sustainable Batteries (Nano-Micro Letters)", "id": "doi 10.1007/s40820-026-02178-9", "url": "https://doi.org/10.1007/s40820-026-02178-9", "year": 2026, "kind": "paper" }, "wiki-graphite": { "title": "Graphite (Wikipedia, sections on natural graphite, milling and synthetic graphite)", "url": "https://en.wikipedia.org/wiki/Graphite", "kind": "web" } }, "license": "CC-BY-4.0", "url": "https://spacemushroom.com/profiles/graphite-anode/" }