Copper Cu

spore: profile
id: copper
spore_version: 0.2
family: copper-alloys
name: Copper
abbreviation: Cu
role: electrical conductor
category: metals
type: copper-alloys
summary: >
  Copper is the element Cu, used as a commercially pure metal for battery negative-electrode foil, wiring and circuit-board traces.
  Annealed oxygen-free copper (C10200) has an electrical conductivity of 100 %IACS, a thermal conductivity of 391 W/(m·K) and a density
  of 8.90 g/cm3, but it is soft, with a typical yield strength of only 69 MPa in the soft temper. In a lithium-ion cell it works only
  while the negative electrode stays low in voltage: a modelling tutorial puts the start of copper dissolution at 3.5 V against Li+/Li.
best_for: "Carrying electricity and heat: 100 %IACS electrical conductivity and 391 W/(m·K) thermal conductivity in the soft oxygen-free grade"
weakest_at: "Strength in the soft state (69 MPa yield), and survival of the cell's copper foil if the cell is over-discharged (dissolution above about 3.5 V vs Li+/Li in a model)"
identity:
  formula: "Cu (element, atomic number 29); commercially pure grade C10200 oxygen-free copper, Cu 99.95 % minimum, O2 10 ppm maximum"
  cas: "7440-50-8"
  source: aurubis-c10200
  where: Composition table of the Aurubis C10200 datasheet (Cu 99.95 min, O2 10 ppm max, Cu includes Ag). CAS number 7440-50-8 is printed against copper in the Sony Energy Devices safety data sheet (see sony-ft40).
tags:
  environments: [low-earth-orbit]
  stresses: [atomic-oxygen, vacuum-and-outgassing]
  applications: [batteries, electronics-and-chips, thermal-control]
properties:
  - benchmark: density
    label: Density, oxygen-free copper C10200
    value: 8.90
    unit: g/cm3
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temperature: "not stated for density in the table (table header gives 20 °C for specific heat, thermal conductivity, modulus and expansion)", unit_in_source: "0.323 lb/in3"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Density
  - benchmark: density
    label: Density, element (PAC Chemical Database)
    value: 8.96
    unit: g/cm3
    scope: material
    conditions: {temperature: "25 °C", form: "copper, CAS 7440-50-8"}
    method: Value listed in the density section of the PubChem record for copper, attributed to the U.S. DOE PAC Chemical Database (other entries in the same record read 8.94)
    status: ground
    note: The same PubChem record lists 8.94 from CAMEO Chemicals, the Merck Index and the NIOSH Pocket Guide with no conditions stated, and a relative density of 8.9 from ICSC. The sources therefore agree within about 0.2 g/cm3.
    source: pubchem-cu
    where: Density section, entry from PAC Chemical Database, U.S. DOE (reference 78)
  - benchmark: melting_point
    label: Melting point, oxygen-free copper C10200
    value: 1083
    unit: °C
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", unit_in_source: "1981 °F", pressure: "not stated"}
    method: Single melting point printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Melting point
  - benchmark: melting_point
    label: Melting point, element (PAC Chemical Database)
    value: 1084.62
    unit: °C
    scope: material
    conditions: {form: "copper, CAS 7440-50-8", pressure: "not stated"}
    method: Value listed in the melting point section of the PubChem record, attributed to the U.S. DOE PAC Chemical Database
    status: ground
    note: The same record lists 1083 °C from the Merck Index (via HSDB) and ICSC.
    source: pubchem-cu
    where: Melting Point section, entry from PAC Chemical Database, U.S. DOE (reference 78)
  - benchmark: electrical_conductivity
    label: Electrical conductivity, soft oxygen-free copper
    value: 58
    unit: MS/m
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temper: "soft (the datasheet says the specified conductivity applies to the soft condition only)", equivalent_in_source: "100 %IACS", temperature: "not stated"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Electrical cond.
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 20 °C
    value: 391
    unit: W/(m·K)
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temperature: "20 °C", unit_in_source: "226 Btu/ft h °F"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Thermal cond. at 20°C
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 77 K, RRR 100 (curve-fit value)
    value: 547
    unit: W/(m·K)
    scope: material
    conditions: {temperature: "77 K", grade: "OFHC copper UNS C10100/C10200, fit for residual resistivity ratio (RRR) 100", fit_range: "4 to 300 K", fit_error: "1 % relative to the data"}
    method: Calculated by Space Mushroom by evaluating the NIST log10 rational-function fit with the RRR = 100 coefficients printed on the NIST page at 77 K (result 547.2); the page tabulates no values
    status: calculated
    note: The same fit gives about 397 W/(m·K) at 293 K, close to the datasheet value of 391 at 20 °C, which supports the transcription. The RRR = 50 fit (error 2 %) gives about 515 W/(m·K) at 77 K, so cryogenic conductivity depends on purity and annealing, which RRR measures.
    source: nist-ofhc
    where: Thermal conductivity coefficient table, RRR = 100 column (a = 2.2154, b = -0.47461, c = -0.88068, d = 0.13871, e = 0.29505, f = -0.02043, g = -0.04831, h = 0.001281, i = 0.003207)
  - benchmark: elastic_modulus
    label: Modulus of elasticity, soft oxygen-free copper
    value: 117
    unit: GPa
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temperature: "20 °C", unit_in_source: "17 x 1000 ksi"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Mod. of elasticity
  - benchmark: cte
    label: Coefficient of thermal expansion at 20 °C
    value: 17.6
    unit: ppm/K
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temperature: "20 °C", unit_in_source: "10-6/K, equal to ppm/K; 9.8 x 10-6/°F"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Coef. of therm exp. at 20°C
  - benchmark: specific_heat
    label: Specific heat capacity at 20 °C
    value: 0.394
    unit: kJ/(kg·K)
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temperature: "20 °C", unit_in_source: "0.092 Btu/lb °F"}
    method: Value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Physical properties table, column Specific heat cap. at 20°C
  - benchmark: yield_strength
    label: Yield strength Rp0.2, soft (annealed) temper
    value: 69
    unit: MPa
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temper: "soft", measure: "Rp0.2 nominal", unit_in_source: "10 ksi", product_form: "strip, rolled product (Aurubis)"}
    method: Nominal value printed in a manufacturer datasheet (leaflet states it is for general information and no warranty)
    status: ground
    note: The same table shows yield rising to 255 MPa in the H02 temper and 359 MPa in H08, so cold work changes strength strongly.
    source: aurubis-c10200
    where: Mechanical properties table, row Soft, column Yield strength Rp0.2
  - benchmark: ultimate_tensile_strength
    label: Tensile strength Rm, soft (annealed) temper
    value: 179
    value_high: 262
    bound: range
    unit: MPa
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temper: "soft", unit_in_source: "26 to 38 ksi", product_form: "strip, rolled product (Aurubis)"}
    method: Range printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Mechanical properties table, row Soft, column Tensile strength Rm
  - benchmark: elongation
    label: Elongation, soft (annealed) temper
    value: 35
    unit: "%"
    scope: material
    conditions: {grade: "C10200 (Cu-OF)", temper: "soft", gauge_length: "2 in. (column header Elongation 2 in.)", basis: "nominal"}
    method: Nominal value printed in a manufacturer datasheet
    status: ground
    source: aurubis-c10200
    where: Mechanical properties table, row Soft, column Elongation 2"
  - benchmark: foil_tensile_strength
    label: Tensile strength of 8 micrometre electrolytic battery-grade copper foil, minimum
    value: 300
    bound: lower
    unit: MPa
    scope: material
    conditions: {product: "Electrolytic Battery Grade Copper Foil, 8 µm row", unit_in_source: "N/mm2", temperature: "room temperature (not stated)", composition: "Cu 99.9 % minimum"}
    method: Minimum value printed in a supplier listing (product listed as no longer available)
    status: ground
    note: The listing is internally inconsistent about which thicknesses exist, and it is a single supplier; treat the value as an example of the foil class, not a standard. Foil is much stronger than annealed strip because it is as-deposited.
    source: cambridge-foil
    where: Specification table, row 8 µm, column Tensile strength (N/mm2)
  - benchmark: foil_elongation
    label: Elongation of 8 micrometre electrolytic battery-grade copper foil, minimum
    value: 3.5
    bound: lower
    unit: "%"
    scope: material
    conditions: {product: "Electrolytic Battery Grade Copper Foil, 8 µm row", temperature: "room temperature (not stated)", gauge_length: "not stated"}
    method: Value printed in a supplier listing (listed as ">3.5")
    status: ground
    source: cambridge-foil
    where: Specification table, row 8 µm, column Elongation (%)
  - benchmark: foil_tensile_hot
    label: Tensile strength of battery-grade copper foil at 180 °C, minimum
    value: 147
    bound: lower
    unit: MPa
    scope: material
    conditions: {product: "Electrolytic Battery Grade Copper Foil", temperature: "180 °C", thickness: "not stated for this row"}
    method: Minimum value printed in a supplier listing
    status: ground
    note: The same listing gives 2 % elongation at 180 °C, so hot foil is weaker and less stretchy than at room temperature.
    source: cambridge-foil
    where: Specifications list, High-temperature tensile strength (180 °C)
  - benchmark: outgassing_rate_baked
    label: Outgassing rate of oxygen-free copper after bake-out
    value: 1.0e-14
    bound: upper
    unit: mbar·l/(s·cm2)
    scope: material
    conditions: {material: "OFS copper (oxygen-free, electronic grade as used at CERN)", treatment: "baked at 200 °C for 24 h, in situ and in vacuum", main_gas: "H2", reported_as: "order of 10-14"}
    method: Order-of-magnitude value in a review table of outgassing rates for selected vacuum materials
    status: ground
    note: This is a rate for particle-accelerator vacuum practice, not a NASA total-mass-loss test, and the bound is given as upper only because the source writes "order of".
    source: chiggiato
    where: Table 5, row OFS copper baked at 200 °C for 24 h
  - benchmark: cu_dissolution_potential
    label: Potential at which copper current-collector dissolution starts (model input)
    value: 3.5
    unit: V vs Li+/Li
    scope: cell
    conditions: {electrolyte: "1 M Li+/PF6- for the reaction; cell electrolyte 1.0 M LiPF6 in EC:EMC (3:7 by weight)", trigger: "cell over-discharge, when the negative electrode potential rises", basis: "equilibrium potential set in a simulation"}
    method: Equilibrium potential used as an input to a finite-element battery model; not a measurement in the tutorial
    status: prediction
    source: comsol-cu
    where: Model Definition section, copper dissolution reaction
  - benchmark: ao_oxide_film_growth
    label: Thickness of a sputtered copper film before and after low Earth orbit exposure, after (increase from 74.2 nm)
    value: 106.7
    unit: nm
    scope: material
    conditions: {experiment: "LDEF experiment A-0114 (University of Alabama in Huntsville)", sample: "sputter-coated copper film on fused silica", before: "74.2 nm +/- 1.1 nm", after: "106.7 nm +/- 0.5 nm", exposure: "atomic oxygen in low Earth orbit; duration not stated in the abstract", measurement: "profilometry"}
    method: Film thickness measured by profilometer before and after flight, reported in a conference abstract; oxides identified as Cu2O and CuO by XPS, AES and XRD
    status: flight
    note: The thickness increase is attributed to oxide growth on the film. Bulk OFHC copper samples were also flown, but no thickness change is given in the abstract.
    source: raikar1992
    where: Abstract
  - benchmark: pcb_copper_fraction
    label: Copper content of printed circuit boards from mobile phones
    value: 34.5
    unit: wt%
    scope: cell
    conditions: {sample: "spent printed circuit boards from mobile phones", method_in_source: "aqua regia leaching with ICP-OES analysis after mineral processing", comparison: "computer boards 20 wt%", metals_fraction_phone: "about 63 wt% metals"}
    method: Value in the abstract of a peer-reviewed study (Yamane et al., Waste Management 2011); open full text not read
    status: ground
    source: yamane2011
    where: Abstract, via the FAPESP publication record
  - benchmark: cell_copper_fraction
    label: Copper share of a lithium-ion polymer battery (Sony Energy Devices FT40 safety data sheet)
    value: 2
    value_high: 15
    bound: range
    unit: wt%
    scope: cell
    conditions: {product: "FT40 lithium ion polymer battery, Sony Energy Devices Corporation", issue_date: "2020-01-01", form: "range stated for the composition table, Copper CAS 7440-50-8"}
    method: Percentage range printed in the composition section of a manufacturer safety data sheet
    status: ground
    note: The brief for this profile mentions a Sony figure of 8 %; the Sony sheet opened gives the range 2 to 15 % instead, and a different maker's sheet gives 7.87 % (next entry).
    source: sony-ft40
    where: Section 3 composition table, row Copper
  - benchmark: cell_copper_fraction
    label: Copper foil share of a lithium-ion pouch battery (Synergy Scientech safety data sheet)
    value: 7.87
    unit: wt%
    scope: cell
    conditions: {product: "AHB advanced hybrid battery with LiCoO2 cathode and carbon anode, Synergy Scientech Corp., Taiwan", sheet_date: "12 April 2007", ingredient_label: "foil, Copper"}
    method: Percentage printed in the ingredients table of a material safety data sheet
    status: ground
    source: synergy-ahb
    where: Section 2 Ingredients/Identity Information, row foil, Copper, 7440-50-8
corrosion:
  - environment: Rural outdoor air
    headline: "Copper tarnishes first to cuprous oxide, then to chloride and sulphide products as air pollutants build up."
    effect: "In a field test of T1 copper (Cu above 99.95 %) in a rural atmosphere in Qingyuan, China, corrosion products were mainly Cu2O in the first six months. After 12 months the products were mainly CuOHCl and CuS. The corrosion rate fell with time as the products covered the surface more densely, and levelled off at 9 and 12 months. Local pitting was seen after one month."
    rating: low
    conditions: {specimen: "T1 copper, 150 mm x 100 mm x 1 mm, Cu above 99.95 mass %", site: "Qingyuan 110 kV substation, Guangdong, rural atmosphere", exposure: "up to 12 months", analysis: "weight loss, SEM, XRD, EDS, EIS"}
    source: liang2015
    where: Abstract, and Results and Discussion section with Figures 1 to 4 (rate values are in the figure only)
  - environment: Atomic oxygen in low Earth orbit
    headline: "Atomic oxygen turns copper surfaces into Cu2O and CuO and thickens the film."
    effect: "Sputtered copper film and bulk OFHC copper flown on LDEF showed copper oxides (Cu2O and CuO) by XPS, AES and XRD. The film thickness measured by profilometry rose from 74.2 nm to 106.7 nm."
    rating: moderate
    conditions: {experiment: "LDEF A-0114", samples: "sputter-coated film on fused silica; solid OFHC copper", exposure_duration: "not given in the abstract"}
    source: raikar1992
    where: Abstract
  - environment: Negative electrode at high potential (lithium-ion cell over-discharge)
    headline: "Copper foil in a cell can start to dissolve if the negative electrode potential rises above about 3.5 V against Li+/Li."
    effect: "A COMSOL battery tutorial says copper current collectors have been seen to dissolve at over-discharge and sets the copper reaction's equilibrium potential to 3.5 V versus Li+/Li in a 1 M Li+/PF6- electrolyte. This is a model input, not a measured corrosion rate."
    rating: severe
    conditions: {basis: "simulation tutorial; no temperature or rate measured", electrolyte: "1.0 M LiPF6 in EC:EMC (3:7 by weight)"}
    source: comsol-cu
    where: Introduction and Model Definition sections
risks:
  hazards:
    - text: "ECHA C&L Inventory (via PubChem), copper EC 231-159-6: of 3,463 company reports, 1,645 gave hazard codes and 1,818 stated that the substance does not meet GHS criteria. Where codes were given: H302 harmful if swallowed (21.7 %), H400 very toxic to aquatic life (43.1 %), H410 very toxic to aquatic life with long lasting effects (18.8 %), H411 toxic to aquatic life with long lasting effects (22.5 %). Signal word Warning; pictograms GHS07 and GHS09. The record notes that classification varies with impurities, additives and form (for example powder versus solid)."
      ghs: [H302, H400, H410, H411]
      source: pubchem-cu
      where: GHS Classification section, ECHA C&L Inventory (reference 35)
    - text: "Sony Energy Devices states in its battery safety data sheet that the batteries are articles under 29 CFR 1910.1200(c) and not subject to the OSHA Hazard Communication Standard; the copper inside the cell (2 to 15 %) is not separately classified there."
      ghs: []
      source: sony-ft40
      where: Sections 3 and 15
  failure_risks:
    - mode: Copper foil dissolution after over-discharge
      trigger: "Negative electrode potential rising above about 3.5 V vs Li+/Li when a cell is discharged far below its normal cut-off"
      consequence: "The tutorial says copper current collectors have been seen to dissolve at over-discharge, which is the damage it simulates. The dissolved copper is a failure mechanism of the cell; the source gives no rate or consequence data."
      severity: moderate
      source: comsol-cu
      where: Introduction and Model Definition
    - mode: Surface tarnish and film growth on exposed copper
      trigger: "Exposure to humid, polluted air, or to atomic oxygen in low Earth orbit"
      consequence: "Cu2O, CuO, CuOHCl and CuS films form. In orbit the film on a sputtered copper layer thickened from 74.2 nm to 106.7 nm. The sources do not report the effect on contact resistance."
      severity: low
      source: raikar1992
      where: Abstract (orbit); see also liang2015 abstract for air
    - mode: Loss of strength of foil when hot
      trigger: "Foil held at 180 °C"
      consequence: "The supplier lists a minimum tensile strength of 147 MPa and 2 % elongation at 180 °C, compared with at least 300 MPa and more than 3.5 % elongation for 8 µm foil at room temperature."
      severity: low
      source: cambridge-foil
      where: Specifications list and 8 µm row of the table
  side_effects:
    - text: "Copper is dense: 8.90 g/cm3 for the soft oxygen-free grade, against 2.7 g/cm3 for aluminium alloy 6061 in this site's profile (different material, shown for scale). The USGS lists aluminium as a substitute for copper in power cable and electrical equipment."
      affects: "Mass of a cell or wiring harness"
      source: aurubis-c10200
      where: Physical properties table (density); USGS substitutes in usgs-mcs2026-copper
  handling:
    - text: "The Aurubis sheet says the specified conductivity applies to the soft condition only, so cold-worked or hard tempers conduct less. It also says the oxygen-free grade has no susceptibility to hydrogen embrittlement, unlike electrolytic tough-pitch copper."
      source: aurubis-c10200
      where: Description paragraph and note under the physical properties table
    - text: "Cells and packs should not be opened, disassembled, crushed or burned (Sony Energy Devices); the copper foil is inside the cell with flammable electrolyte."
      source: sony-ft40
      where: Section 10 Conditions to Avoid
  mitigations: []
uses:
  - application: batteries
    device: "Negative-electrode current collector foil in lithium-ion cells"
    example: "Sony Energy Devices lists copper at 2 to 15 % of the FT40 lithium ion polymer battery, and a Synergy Scientech sheet lists copper foil at 7.87 % of a LiCoO2 / carbon pouch cell. Battery-grade electrolytic foil is sold as 7, 8 and 9 µm rolls (supplier listing)."
    source: sony-ft40
    where: Section 3 composition table; see also synergy-ahb and cambridge-foil
  - application: electronics-and-chips
    device: "Printed circuit boards"
    example: "Spent mobile phone boards contain 34.5 wt% copper, against 20 wt% for computer boards (Yamane et al. 2011). Aurubis lists printed circuits, flexible circuits, contacts and terminals among typical uses of C10200."
    source: yamane2011
    where: Abstract; aurubis-c10200 Typical uses
  - application: thermal-control
    device: "Heat spreading and conductive paths"
    example: "Thermal conductivity of 391 W/(m·K) at 20 °C for oxygen-free copper. The USGS says copper can replace aluminium in electrical and heat-exchange applications."
    source: aurubis-c10200
    where: Physical properties table
  - application: electronics-and-chips
    device: "Telecommunication cables and electrical conductors"
    example: "Aurubis lists telecommunication cables, electrical and electronic conductors and terminal lugs as typical uses. Per the Copper Development Association, as cited by the USGS, electrical and electronic products took 23 % of U.S. copper and copper-alloy use."
    source: usgs-mcs2026-copper
    where: Domestic Production and Use paragraph
supply:
  - subject: Copper (mine and refinery production)
    producers:
      - {country: Chile, share_percent: 23.0, year: 2025}
      - {country: Congo (Kinshasa), share_percent: 13.9, year: 2025}
      - {country: Peru, share_percent: 11.7, year: 2025}
      - {country: China, share_percent: 7.8, year: 2025}
      - {country: Russia, share_percent: 5.7, year: 2025}
    critical_lists:
      - {list: "U.S. Final 2025 List of Critical Minerals (copper added; USGS Mineral Commodity Summaries 2026)", listed: true}
    recycling: "USGS: in 2025 old (post-consumer) scrap provided an estimated 160,000 tons of copper and about 760,000 tons were recovered from new (manufacturing) scrap; brass and wire-rod mills took about 80 % of the copper recovered from scrap, and scrap contributed about 30 % of the U.S. copper supply."
    substitutes: ["USGS: aluminium substitutes for copper in automobile radiators, cooling and refrigeration tube, electrical equipment and power cable; optical fibre substitutes in telecommunications; plastics in drain pipe, plumbing fixtures and water pipe; titanium and steel in heat exchangers."]
    source: usgs-mcs2026-copper
    where: "World Mine and Refinery Production and Reserves table, mine production 2025e (world total 23,000 thousand t, copper content; shares calculated by Space Mushroom from the country values 5,300; 3,200; 2,700; 1,800; 1,300; the top three sum to 11,200 or 48.7 % of the world total); Recycling; Substitutes; Events, Trends, and Issues. World refinery production 2025e 29,000 thousand t; world reserves 980,000 thousand t."
documents:
  - {title: "Wikipedia: Copper (crystal structure, smelting and refining)", type: database, url: "https://en.wikipedia.org/wiki/Copper", year: 2026}
  - {title: "Aurubis technical datasheet C10200 (Cu-OF), 18 08 US", type: datasheet, url: "https://www.aurubis.be/en/dam/jcr:90029b00-b968-486e-bde0-ce56f16022cd/c10200-cu-of-us.pdf"}
  - {title: "NIST Cryogenic Material Properties: OFHC Copper (UNS C10100/C10200)", type: database, url: "https://trc.nist.gov/cryogenics/materials/OFHC%20Copper/OFHC_Copper_rev1.htm"}
  - {title: "USGS Mineral Commodity Summaries 2026: Copper", type: report, url: "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf", year: 2026}
  - {title: "PubChem compound record for copper (ECHA C&L Inventory, density, melting point)", type: database, url: "https://pubchem.ncbi.nlm.nih.gov/compound/Copper"}
  - {title: "Sony Energy Devices safety data sheet, FT40 lithium ion polymer battery (2020)", type: sds, url: "https://static.lenovo.com/ww/docs/regulatory/msds/FT40-Sony-SDS.pdf", year: 2020}
  - {title: "Synergy Scientech material safety data sheet, AHB advanced hybrid battery (2007)", type: sds, url: "http://sds.staples.com/msds/344117.pdf", year: 2007}
  - {title: "Yamane et al., Recycling of WEEE: Characterization of spent printed circuit boards from mobile phones and computers, Waste Management 31(12), 2011", type: paper, url: "https://bv.fapesp.br/en/publicacao/54227/recycling-of-weee-characterization-of-spent-printed-circuit", year: 2011}
  - {title: "COMSOL 6.4 model: Copper Current-Collector Dissolution", type: report, url: "https://doc.comsol.com/6.4/doc/com.comsol.help.models.battery.cu_current_collector_dissolution/cu_current_collector_dissolution.html"}
  - {title: "Raikar et al., Interaction of atomic oxygen with thin film and bulk copper (LDEF A-0114), NTRS 19920018059", type: paper, url: "https://ntrs.nasa.gov/citations/19920018059", year: 1992}
  - {title: "Chiggiato, Vacuum Technology for Superconducting Devices (CERN), arXiv:1501.07162", type: paper, url: "https://arxiv.org/abs/1501.07162"}
  - {title: "Liang et al., Study of T1 Copper Corrosion Behavior in Qingyuan Rural Atmosphere (MMECEB 2015)", type: paper, url: "https://www.atlantis-press.com/article/25847184.pdf", year: 2015}
gaps:
  - "The copper process steps are taken from Wikipedia and the USGS 2026 summary only; the USGS mine and refinery process text and an industry process reference were not opened, so the electrowinning step is not described from a primary source."
  - "The Sony safety data sheet with copper at exactly 8 % of a lithium-ion pack was not found. The Sony Energy Devices FT40 sheet gives copper as 2 to 15 %, and a Synergy Scientech sheet gives copper foil as 7.87 %. Both are recorded instead."
  - "Phone circuit boards 'about a third copper': the 34.5 wt% value comes from the abstract of Yamane et al. 2011 as shown on a FAPESP record; the journal full text (Elsevier, 403 error) and the Kasper et al. 2011 abstract were not opened, so method details beyond the abstract are not recorded."
  - "No NASA outgassing test (total mass loss, collected volatile condensable material) for copper was found; the NASA database entry was not located. Copper vapour-pressure data were also not found in an openly readable source, so the vacuum section rests on the baked-copper outgassing rate from a CERN review only."
  - "Cold welding or galling of bare copper in vacuum: no value or flight result was opened (a 1967 Franklin Institute report on cohesion of metals was named in a search result but not read)."
  - "Atomic oxygen: LDEF abstracts do not give exposure duration or an erosion or reaction yield for copper; a mass-gain or oxide thickness per fluence was not found."
  - "Atmospheric corrosion rate in micrometres per year: the rural-atmosphere paper gives rates only as a figure; ISO 9223 bands and long-term exposure studies were seen only through search snippets and were not opened, so no rate is recorded."
  - "Electrical resistivity at 20 °C in ohm-metres, and temperature coefficient of resistance, were not found as separate values; only the 58 MS/m (100 %IACS) conductivity from a datasheet is recorded."
  - "Thermal conductivity of foil as deposited, and electrical conductivity of battery-grade foil, were not found."
  - "Minimum or typical yield and tensile values for ETP (C11000) and oxygen-free copper from ASTM B152 or the Copper Development Association were not opened; the strength values come from one manufacturer datasheet (soft strip)."
  - "Radiation effects on copper (displacement damage, total dose) were not looked up."
  - "Emissivity of copper: a CERN lecture uses 0.02 for clean copper as a worked-example assumption, but it is not a measured value and is not recorded."
  - "Crustal abundance of copper and the share of copper in lunar or Martian regolith were not looked up. The USGS global resource figures (identified 1.5 billion tons, undiscovered 3.5 billion tons as of 2015) were read but are not entered as properties."
sources:
  wikipedia-cu:
    title: "Copper (crystal structure, smelting and refining)"
    url: https://en.wikipedia.org/wiki/Copper
    year: 2026
    kind: web
    license: CC BY-SA 4.0 (cited, not reproduced)
  aurubis-c10200:
    title: "Technical Datasheet C10200 (Cu-OF), Aurubis, version 18 08 US"
    id: "UNS C10200, EN CW008A, JIS C1020; ASTM B152, ASME SB152"
    url: https://www.aurubis.be/en/dam/jcr:90029b00-b968-486e-bde0-ce56f16022cd/c10200-cu-of-us.pdf
    kind: datasheet
    license: Manufacturer leaflet, general information only, no warranty (cited, not reproduced)
  nist-ofhc:
    title: "Material Properties: OFHC Copper (UNS C10100/C10200), NIST Cryogenic Material Properties"
    id: "NIST Cryogenics Technologies Group, curve fits for 4 to 300 K"
    url: https://trc.nist.gov/cryogenics/materials/OFHC%20Copper/OFHC_Copper_rev1.htm
    kind: database
    license: NIST public web page
  pubchem-cu:
    title: "PubChem compound record: Copper (CID 23978), including ECHA C&L Inventory classification"
    id: "CAS 7440-50-8, EC 231-159-6"
    url: https://pubchem.ncbi.nlm.nih.gov/compound/Copper
    kind: database
    license: PubChem (NCBI), public domain; sections attributed to ECHA, DOE PAC database and others
  usgs-mcs2026-copper:
    title: Mineral Commodity Summaries 2026, Copper
    id: "USGS MCS 2026, February 2026"
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  sony-ft40:
    title: "Safety Data Sheet: FT40 lithium ion polymer battery, Sony Energy Devices Corporation (copy hosted by Lenovo, issue date 2020-01-01)"
    url: https://static.lenovo.com/ww/docs/regulatory/msds/FT40-Sony-SDS.pdf
    year: 2020
    kind: datasheet
    license: Manufacturer safety data sheet (cited, not reproduced)
  synergy-ahb:
    title: "Material Safety Data Sheet: AHB advanced hybrid batteries, Synergy Scientech Corp. (second edition, 12 April 2007)"
    id: "NSN 614000N078675"
    url: http://sds.staples.com/msds/344117.pdf
    year: 2007
    kind: datasheet
    license: Manufacturer safety data sheet (cited, not reproduced)
  yamane2011:
    title: "Recycling of WEEE: Characterization of spent printed circuit boards from mobile phones and computers (Yamane, de Moraes, Espinosa, Tenorio), Waste Management 31(12), 2553-2558"
    id: "DOI 10.1016/j.wasman.2011.07.006"
    url: https://bv.fapesp.br/en/publicacao/54227/recycling-of-weee-characterization-of-spent-printed-circuit
    year: 2011
    kind: paper
    license: Abstract read via FAPESP publication record (cited, not reproduced)
  comsol-cu:
    title: "COMSOL 6.4 Application: Copper Current-Collector Dissolution"
    url: https://doc.comsol.com/6.4/doc/com.comsol.help.models.battery.cu_current_collector_dissolution/cu_current_collector_dissolution.html
    kind: web
    license: COMSOL documentation (cited, not reproduced)
  raikar1992:
    title: "Interaction of atomic oxygen with thin film and bulk copper: An XPS, AES, XRD, and profilometer study (Raikar, Gregory, Christl, Peters), LDEF experiment A-0114"
    id: "NTRS 19920018059; Second LDEF Post-Retrieval Symposium Abstracts, 1992"
    url: https://ntrs.nasa.gov/citations/19920018059
    year: 1992
    kind: paper
    license: public domain (NASA)
  chiggiato:
    title: "Vacuum Technology for Superconducting Devices (P. Chiggiato, CERN)"
    id: "arXiv:1501.07162"
    url: https://arxiv.org/abs/1501.07162
    kind: paper
    license: arXiv preprint (cited, not reproduced)
  cambridge-foil:
    title: "Electrolytic Battery Grade Copper Foil (Cambridge Energy Solutions supplier listing, product no longer available)"
    url: https://cambridge-energy-solutions-ltd.odoo.com/shop/electrolytic-battery-grade-copper-foil-1720
    kind: datasheet
    license: Supplier web page (cited, not reproduced)
  liang2015:
    title: "Study of T1 Copper Corrosion Behavior in Qingyuan Rural Atmosphere (Liang, Yang, Kuang), MMECEB 2015, Atlantis Press"
    url: https://www.atlantis-press.com/article/25847184.pdf
    year: 2015
    kind: paper
    license: Atlantis Press open access (cited, not reproduced)
license: CC-BY-4.0

updated: "2026-10-17"
review:
  status: draft
  method: assistant
  checked_values: 22
  unreachable: 1
  caveats: 6
  note: "Values were read by an AI assistant on 2026-10-17 from the pages and PDFs named in each entry (datasheet and USGS text extracted from the PDF; NIST value recomputed from printed coefficients). Unreachable: the Yamane full text. Caveats: datasheet strengths are nominal values of one manufacturer; the foil values come from a single supplier listing that is no longer sold; the 3.5 V dissolution potential is a model input; the outgassing rate is an order of magnitude from accelerator practice; the Sony 8 % figure was not found, only 2 to 15 %; the 34.5 wt% value is from an abstract."

story:
  risk_groups:
    - title: For people
      lead: "The classification of copper depends on who notified it, and the opened sources do not describe health effects of copper foil inside a sealed cell."
      level: 1
      verdict: "Mixed notifications"
      points:
        - label: Copper as a substance
          line: "Of 3,463 company reports to the European chemicals agency, 1,818 said copper does not meet the hazard criteria. Among reports that gave codes, 43.1 % listed very toxic to aquatic life (H400) and 21.7 % listed harmful if swallowed (H302). The signal word is Warning."
        - label: Copper inside a battery
          line: "Sony Energy Devices treats its battery as an article that does not fall under the U.S. hazard communication rule, and lists copper at 2 to 15 % of the cell. The sheet says the cell should not be opened, crushed or burned."
    - title: If it fails
      lead: "These are failure routes found in the sources. Only one of them is a measured result from space; the others are a model and a field test."
      points:
        - label: Over-discharge of a cell
          line: "A battery tutorial says copper current collectors have been seen to dissolve at over-discharge, and it models the start of dissolution at 3.5 V against Li+/Li. That is a simulation input, not a measured rate."
        - label: Tarnish
          line: "In rural air copper first forms Cu2O, and after 12 months mainly CuOHCl and CuS. In low Earth orbit a copper film flown on LDEF thickened from 74.2 nm to 106.7 nm as oxides formed."
        - label: Hot foil
          line: "A supplier lists at least 147 MPa and 2 % elongation for battery foil at 180 °C, compared with at least 300 MPa and more than 3.5 % elongation for 8 µm foil at room temperature."
    - title: Handling and storage
      points:
        - label: Keep it soft or hard on purpose
          line: "The datasheet says the quoted conductivity applies to the soft condition only. Yield strength is 69 MPa when soft and rises to 359 MPa in the H08 temper."
        - label: Cells
          line: "Do not open, crush or burn batteries. The copper foil sits next to flammable electrolyte."
  why: >-
    Copper is a very good conductor of both electricity and heat.
    In its soft oxygen-free grade, C10200, the electrical conductivity is 100 %IACS (58 MS/m) and the thermal conductivity is 391 W/(m·K) at 20 °C.
    That is why copper turns up wherever current has to travel with little loss: as thin foil that collects current from the negative electrode of
    a lithium-ion cell, as wire, and as the traces on circuit boards. A Sony Energy Devices safety data sheet lists copper at 2 to 15 % of one
    of its batteries, a Synergy Scientech sheet lists copper foil at 7.87 % of another, and a published study found 34.5 wt% copper in phone circuit
    boards. If a cell is over-discharged, the electrode voltage
    rises, and a modelling tutorial puts the start of copper dissolution at 3.5 V against Li+/Li. Copper is heavy (8.90 g/cm3) and, when annealed, soft.
  uses:
    - where: Battery foil
      line: >-
        Copper is the current collector for the negative electrode. Battery-grade electrolytic foil is sold in thicknesses of 7, 8 and 9 µm in one
        supplier listing, with a minimum tensile strength of 300 MPa.
    - where: Circuit boards and wiring
      line: >-
        Spent mobile phone boards are 34.5 wt% copper against 20 wt% for computer boards. The datasheet lists printed circuits, flexible circuits,
        telecommunication cables, contacts and terminals among typical uses of C10200.
    - where: Vacuum hardware
      line: >-
        Oxygen-free copper baked at 200 °C for 24 h reaches an outgassing rate of order 10-14 mbar·l/(s·cm2), mostly hydrogen, according to a CERN review.
  can_do:
    - label: Carry current
      value: 58 MS/m (100 %IACS)
      line: >-
        Soft oxygen-free copper conducts at 58 MS/m, the reference value of 100 %IACS. The datasheet says this applies to the soft condition only.
    - label: Carry heat
      value: 391 W/(m·K)
      benchmark: thermal_conductivity
      line: >-
        Thermal conductivity at 20 °C is 391 W/(m·K), meaning heat flows through a metre-thick slab at 391 W for each kelvin of difference per square metre.
        At 77 K a NIST curve fit for RRR 100 copper gives about 547 W/(m·K), and for RRR 50 about 515, so cold conductivity depends on purity and annealing.
    - label: Weight
      value: 8.90 g/cm3
      benchmark: density
      line: >-
        Density is 8.90 g/cm3 in the datasheet, and 8.96 g/cm3 at 25 °C in the DOE database entry quoted by PubChem.
    - label: Melting
      value: 1083 °C
      line: >-
        The datasheet gives a melting point of 1083 °C, and the DOE database entry gives 1084.62 °C.
    - label: Strength when soft
      value: 69 MPa yield
      line: >-
        Annealed strip has a nominal yield strength of 69 MPa and a tensile strength of 179 to 262 MPa, stretching 35 % before breaking.
        The modulus of elasticity, a measure of stiffness, is 117 GPa.
    - label: Foil strength
      value: at least 300 MPa
      line: >-
        An 8 µm electrolytic battery foil from one supplier is listed at a minimum of 300 MPa and more than 3.5 % elongation, far stronger and less stretchy than annealed strip.
    - label: Expansion and heat storage
      value: 17.6 ppm/K
      benchmark: cte
      line: >-
        The coefficient of thermal expansion at 20 °C is 17.6 ppm/K, so a length changes by 17.6 millionths per kelvin. Specific heat is 0.394 kJ/(kg·K).
  compare: >-
    The USGS says aluminium substitutes for copper in electrical equipment and power cable, and copper can replace aluminium in electrical and
    heat-exchange uses. In this site's aluminium 6061 profile the density is 2.7 g/cm3, against
    8.90 g/cm3 here, but the two profiles use different alloys and grades, so read the table rows as examples, not a ranking.
  compare_rows:
    - {label: Density, benchmark: density}
    - {label: Thermal conductivity, benchmark: thermal_conductivity}
    - {label: Thermal expansion, benchmark: cte}
  handling:
    - Specify the temper, because conductivity applies to the soft condition and strength rises a lot with cold work.
    - Keep battery cells away from over-discharge, since copper foil can dissolve once the negative electrode rises above about 3.5 V against Li+/Li (model).
    - Do not open, crush or burn cells.
  good_for:
    - "Conducting current and heat: 100 %IACS and 391 W/(m·K) in soft oxygen-free copper."
    - "Recyclability: scrap provides about 30 % of the U.S. copper supply, per the USGS."
    - "Clean vacuum service: baked oxygen-free copper outgasses at order 10-14 mbar·l/(s·cm2)."
  watch_out:
    - "Soft copper is weak: 69 MPa yield in the annealed temper."
    - "Weight: 8.90 g/cm3, so aluminium is the usual substitute where mass matters."
    - "Over-discharge of a cell can dissolve the copper foil, according to a model that sets the start at 3.5 V against Li+/Li."
    - "The 2025 supply is concentrated: Chile, Congo (Kinshasa) and Peru together mined about 48.7 % of world copper, and copper was added to the U.S. critical minerals list in 2025."
    - "No total-mass-loss outgassing test, cold-welding result or atomic-oxygen erosion yield was found for this profile."
  verdict: "Copper is the standard conductor of current and heat, with 100 %IACS and 391 W/(m·K) in the soft oxygen-free grade. It is heavy, soft when annealed, tarnishes into oxide films in air and in orbit, and in a battery it relies on the negative electrode staying below about 3.5 V against Li+/Li. This profile lacks NASA outgassing, cold-welding and erosion-yield numbers."
  recipe:
    line: "Copper is a single-element metal (Cu) with a face-centred cubic crystal structure (Wikipedia). Most copper ores are sulfides, so they are smelted, and the smelting step gives sulfur dioxide unless it is captured (Wikipedia). The smelted blister copper is then refined and cast into ingots (Wikipedia). USGS Mineral Commodity Summaries lists primary smelters and electrolytic and electrowon refineries in the United States, and imports of copper as blister, anodes, matte and concentrate."
    parts:
      - name: Copper
        symbol: Cu
        atoms: 1
        atomic_weight: 63.55
        role: "The whole material. PubChem prints the molecular weight of the element as 63.55."