spore: profile
id: lithium-nickel-oxide
spore_version: 0.2
family: lithium
name: Lithium nickel oxide
abbreviation: LNO
role: cathode
category: energy
type: li-ion-cathodes
summary: |
  Lithium nickel oxide (LiNiO2) is the layered cathode oxide that sits at the nickel end of the NCA and NMC families. It has the same layered structure as lithium cobalt oxide but with nickel in place of cobalt. A Sony lithium-ion polymer pack safety data sheet lists it at 27% of the pack as active material, next to 7% lithium cobalt oxide. Pure LiNiO2 has a high theoretical capacity but is hard to make with an ideal structure, fades quickly when cycled, and loses oxygen when heated or highly charged, so commercial cells use nickel-rich blends and doped versions instead.
best_for: High theoretical capacity from a cobalt-free layered oxide, and the model material for nickel-rich cathodes
weakest_at: Cycling stability and thermal stability, caused by nickel sitting in lithium sites and by a damaging phase change at high charge
identity:
  formula: LiNiO2
  cas: 12031-65-1
  crystal_system: trigonal (layered, rhombohedral cell)
  space_group: R-3m
  source: acta-b-2026
  where: Results (single-crystal refinement); CAS from the Sony and Stanford Advanced Materials safety data sheets
tags:
  environments: []
  stresses:
    - extreme-heat
  applications:
    - batteries
properties:
  - benchmark: theoretical_capacity
    value: 275
    unit: mAh/g
    scope: material
    conditions:
      basis: stated in the introduction as the highest theoretical capacity of the NCA and NCM families, with LiNiO2 as their end member
    method: Review statement in a computational paper (value not recomputed here)
    status: calculated
    note: The ijms-2026 review gives "close to 250 mAh g-1" in one place and about 275 in another, so the sources disagree.
    source: cheng-2023
    where: Introduction, paragraph 2
  - benchmark: theoretical_capacity
    label: Theoretical capacity, lower figure quoted in the same review
    value: 250
    unit: mAh/g
    scope: material
    conditions:
      basis: described as 'close to 250'; the review also gives approximately 275 in its critical assessment
    method: Review statement
    status: calculated
    note: Shown so the disagreement between 250 and 275 stays visible. The cheng-2023 value of 275 is the figure used in the story.
    source: ijms-2026
    where: Section 3.1.2 (Lithium Nickel Oxide)
  - benchmark: avg_voltage
    value: 4
    unit: V vs Li/Li+
    scope: material
    conditions:
      basis: described as approximately 4 V average operating voltage; cell format and rate not stated
    method: Review statement
    status: ground
    source: ijms-2026
    where: Section 3.1.2
  - benchmark: density
    label: Electrode density
    value: 3.3
    unit: g/cm3
    scope: material
    conditions:
      basis: described as an electrode density of about 3.3, not a crystallographic density
    method: Review statement
    status: ground
    note: This is an electrode density, so it includes pores and is lower than the density of the pure crystal.
    source: ijms-2026
    where: Section 3.1.2
  - benchmark: lattice_parameter_a
    label: Lattice parameter a (2 x 2 superstructure cell)
    value: 5.8247
    unit: Angstrom
    scope: material
    conditions:
      sample: LiNiO2 single crystal grown by optical floating zone
      temperature: 300 K
      cell: rhombohedral, 2 x 2 superstructure
      uncertainty: 0.0002 as printed, (2) in the last digit
    method: Single-crystal X-ray diffraction refinement
    status: ground
    source: acta-b-2026
    where: Results, text before Table 1
  - benchmark: lattice_parameter_c
    label: Lattice parameter c (2 x 2 superstructure cell)
    value: 14.271
    unit: Angstrom
    scope: material
    conditions:
      sample: LiNiO2 single crystal grown by optical floating zone
      temperature: 300 K
      cell: rhombohedral, 2 x 2 superstructure
      uncertainty: (4) in the last digit
    method: Single-crystal X-ray diffraction refinement
    status: ground
    source: acta-b-2026
    where: Results, text before Table 1
  - benchmark: ionic_radius_ni2
    label: Ionic radius of Ni2+ (compared with Li+ at 0.76 Angstrom)
    value: 0.69
    unit: Angstrom
    scope: material
    conditions:
      compared_with: Li+ 0.76, Ni3+ 0.56, Ni4+ 0.48 Angstrom
      basis: reference 61 of the source
    method: Tabulated ionic radii quoted in a computational paper
    status: calculated
    note: This closeness of Ni2+ and Li+ is why nickel can sit in lithium sites.
    source: komurcuoglu-2024
    where: Discussion of why Ni2+ is the migrating species (page 15 of the preprint)
  - benchmark: o1_onset_delithiation
    label: Delithiation where the damaging O3-to-O1 phase appears
    value: 75
    unit: '% of lithium removed'
    scope: material
    conditions:
      basis: pristine LiNiO2, cluster-expansion and Monte Carlo simulation
      detail: all Li(1-x)NiO2 structures are O3 for x below 0.75; the O1-3 phase emerges above that
    method: First-principles phase-diagram calculation
    status: prediction
    note: The paper also says this O3 to O1 shift is sometimes called H2 to H3, and that it causes cracking and oxygen loss.
    source: cheng-2023
    where: Results; Introduction
  - benchmark: cycle_life
    label: Capacity retention of undoped LNO after 100 cycles
    value: 69.2
    unit: '% retained'
    scope: cell
    conditions:
      rate: 0.5 C
      cycles: 100
      comparison: LiNi0.99Nb0.01O2 retained 91.4% under the same conditions
      voltage_window_and_temperature: not stated in the review
    method: Reported in a review of a niobium-doping study (Huang et al.)
    status: ground
    note: The review's Table 5 also lists LNO capacity retention as "Poor undoped (<70%@100)". Second-hand.
    source: ijms-2026
    where: Section 3.1.2; Table 5
  - benchmark: lithiated_rock_salt_onset
    label: Onset of layered to rock-salt breakdown on heating (lithiated LNO, oxygen)
    value: 350
    unit: degC
    scope: material
    conditions:
      sample: thinned LiNiO2 particles, as made (not charged)
      atmosphere: 1 bar oxygen, flowing at 0.1 mL/min in a closed gas cell
      method_limit: spinel-type phases seen up to 400 degC, then a crack ended the run
    method: In situ 4D nanobeam STEM heating
    status: ground
    note: Approximate onset ("about 350") of changes at grain boundaries and structural degradation. The authors say onset is higher than in vacuum heating experiments, and that XRD studies of bulk LNO report stability above 600 degC, so this number depends strongly on method and oxygen pressure.
    source: demuth-2025
    where: Abstract; Results
  - benchmark: thermal_stability_table
    label: Thermal stability (comparison-table figure)
    value: 190
    value_high: 210
    bound: range
    unit: degC
    scope: material
    conditions:
      basis: column headed Thermal Stability (degC) in a literature comparison table; the definition of the figure is not given
      compared_with: NMC333 250 to 300, NMC622/NMC811 190 to 240, NCA 210 to 230, LCO about 200 degC in the same table
    method: Literature comparison table
    status: ground
    note: The table does not say whether this is an onset or a peak, or at what state of charge. Treat as indicative only.
    source: ijms-2026
    where: Table 5
  - benchmark: molar_mass
    value: 97.63
    unit: g/mol
    scope: material
    conditions:
      basis: stated formula weight of LiNiO2; PubChem gives 97.7
    method: Supplier SDS statement
    status: calculated
    source: sa-sds
    where: Section 3
  - benchmark: pack_active_fraction
    label: Share of pack mass listed as lithium nickel oxide (active material)
    value: 27
    unit: '% of pack'
    scope: cell
    conditions:
      product: Sony NP-BX1 / SP94BPIN2C lithium ion polymer battery pack, one SP943043N cell
      basis: concentration listed in SDS section 3 for 'Lithium Nickel Oxides (active material)', CAS 12031-65-1
      compared_with: 7% lithium cobalt oxide, 28% carbon, 14% aluminum, 8% copper
    method: Manufacturer safety data sheet composition table
    status: ground
    note: The sheet lists concentration, not whether the material is pure LiNiO2 or a doped or blended nickel oxide; the CAS number given is that of LiNiO2. The sheet is dated 1 Jan 2019.
    source: sony-sds
    where: Section 3 (Composition)
  - benchmark: avg_voltage
    label: Pack average operating voltage (Sony NP-BX1)
    value: 3.6
    unit: V
    scope: cell
    conditions:
      product: Sony NP-BX1 pack with one lithium ion polymer cell
      rated_capacity: 1240 mAh (4.5 Wh)
    method: Manufacturer safety data sheet
    status: ground
    note: A property of the finished pack, which blends lithium nickel oxide with lithium cobalt oxide, not of LiNiO2 alone.
    source: sony-sds
    where: Section 1 and Section 9
  - benchmark: operating_temperature_range
    label: Allowed discharge temperature range of the Sony pack
    value: -10
    value_high: 60
    bound: range
    unit: degC
    scope: cell
    conditions:
      product: Sony NP-BX1 pack
      charge_limits: 0 to 45 degC
      storage: '-10 to 30 degC recommended, not above 60 degC'
    method: Manufacturer safety data sheet handling limits
    status: ground
    source: sony-sds
    where: Section 7
corrosion:
  - environment: Heat in the charged state, with electrolyte
    headline: A charged LNO cell loses oxygen and ignites when abused; the Sony sheet warns of ignition above 100 degC.
    effect: The Sony sheet says external short-circuit, crushing, or exposure of the pack to high temperature (over 100 degC) generates heat and ignition. This is a statement about the whole pack, which contains lithium nickel oxide, lithium cobalt oxide and flammable organic electrolyte, not about LiNiO2 alone.
    rating: unknown
    conditions:
      product: Sony NP-BX1 lithium ion polymer pack
      note: no measurement of LNO-specific corrosion found
    source: sony-sds
    where: Section 10
risks:
  hazards:
    - text: 'PubChem GHS section for lithium nickel dioxide (CID 3035375), first block: signal word Danger. H317 May cause an allergic skin reaction; H350i May cause cancer by inhalation; H372 Causes damage to organs through prolonged or repeated exposure. The block''s source is not named in the data returned.'
      ghs:
        - H317
        - H350i
        - H372
      source: pubchem-lno
      where: GHS Classification, first block
    - text: 'PubChem aggregate of ECHA C&L Inventory notifications (163 reports from 9 notifications): H317 in 100%, H350 in 99.4%, H372 in 100%; signal word Danger.'
      ghs:
        - H317
        - H350
        - H372
      source: pubchem-lno
      where: GHS Classification, ECHA C&L Notifications Summary
    - text: 'Supplier safety data sheet (Stanford Advanced Materials, revised 05/02/2023, for research use): skin sensitisation category 1 and carcinogenicity category 2, signal word Warning. This is milder than the ECHA aggregate above, so the sources disagree.'
      ghs:
        - H317
        - H351
      source: sa-sds
      where: Section 2
    - text: 'Sony NP-BX1 pack safety data sheet (Tohoku Murata, 1 Jan 2019): not applicable for regulated class. Hazards given are heat or electrolyte leakage if terminals touch metal, flammable electrolyte, and irritating fumes from burning cells; UN3480.'
      ghs: []
      source: sony-sds
      where: Sections 2 and 3
  failure_risks:
    - mode: Heating or abuse of a pack containing LNO
      trigger: External short-circuit, crush, or exposure to temperatures over 100 degC
      consequence: The Sony sheet says the pack generates heat and ignites. It also says burning gives off irritating vapor and that corrosive gas may be produced when extinguishing.
      severity: high
      source: sony-sds
      where: Sections 2, 5 and 10
    - mode: Oxygen loss and breakdown to rock salt on heating
      trigger: Heating LiNiO2 particles in 1 bar oxygen to about 350 degC
      consequence: The layered structure begins degrading toward a NiO-type rock-salt phase, with spinel-type regions and cracking above 350 degC. The authors note this is higher than in vacuum.
      severity: high
      source: demuth-2025
      where: Abstract; Results
    - mode: Phase change at high charge
      trigger: Removing more than 75% of the lithium (high voltage)
      consequence: The paper predicts the O3-to-O1 transition, which it says promotes cracking and oxygen loss and is linked to poor cycling of LiNiO2.
      severity: moderate
      source: cheng-2023
      where: Introduction; Results
    - mode: Nickel in lithium sites (cation mixing)
      trigger: Making LiNiO2 by conventional solid-state synthesis, which gives extra Ni in the Li layer
      consequence: Ni atoms in the Li layer block lithium paths and lower capacity and cycling, according to the studies the paper cites.
      severity: moderate
      source: komurcuoglu-2024
      where: Introduction
  side_effects:
    - text: Compared with LiNiO2, LiNi0.5Mn0.5O2 is described as having improved thermal stability and cycling performance, which is the reason mixed-metal layered oxides replaced pure LNO.
      affects: Cathode choice in cells
      source: ijms-2026
      where: Section 3.1.5 area (LiNi0.5Mn0.5O2 paragraph)
  handling:
    - text: 'Sony pack: store at -10 to 30 degC in a well-ventilated area, do not expose to 60 degC, do not disassemble, short, crush or incinerate, charge only at 0 to 45 degC with the specified charger.'
      source: sony-sds
    - text: 'Powder SDS: avoid breathing dust, wear protective gloves, store locked up, wash contaminated clothing, and dispose at an approved waste disposal plant (precautionary statements P261, P280, P405, P501).'
      source: sa-sds
  mitigations:
    - text: Doping and mixed-metal compositions are the studied route to reduce the problems of pure LNO. A simulation found at least 10% Al or Mg was needed to prevent the O3-to-O1 change in pristine-type LNO, while the review lists Nb, La, Mg and W doping as experimental routes.
      source: cheng-2023
uses:
  - application: batteries
    device: Lithium-ion polymer pack, camera battery (Sony NP-BX1)
    example: Listed at 27% of the pack as lithium nickel oxide active material, with 7% lithium cobalt oxide, in the Sony NP-BX1 pack (1240 mAh, 4.5 Wh, average 3.60 V).
    source: sony-sds
  - application: batteries
    device: Parent compound of NCA and NMC cathodes
    example: Cheng et al. call LiNiO2 the ultimate end member of the NCA and NMC families; NMC compositions moved from 33% Ni (NMC111) to 60% (NMC622) and 80% (NMC811).
    source: cheng-2023
  - application: batteries
    device: Model material for cobalt-free nickel-rich cathodes
    example: A computational paper uses LiNiO2 as a model for the atomic-scale behavior of Co-free Ni-rich cathodes.
    source: komurcuoglu-2024
supply:
  - subject: Nickel (the metal in LiNiO2)
    abundance: Estimated 2025 world nickel mine production was 3,900,000 tons; Indonesia produced 2,600,000 tons, about two thirds (calculated from those two figures), followed by the Philippines at 270,000 tons and Russia at 200,000 tons. World reserves are above 140,000,000 tons.
    producers:
      - country: Indonesia
        share_percent: 67
        year: 2025
      - country: Philippines
        share_percent: 7
        year: 2025
    critical_lists: []
    recycling: In the United States, nickel recovered from scrap was about 60% of apparent consumption in 2025, mostly stainless-steel scrap; battery recycling is not broken out.
    substitutes: []
    source: usgs-nickel-2026
    where: World Mine Production and Reserves table; Recycling
media: []
documents:
  - title: Sony NP-BX1 / SP94BPIN2C safety data sheet (Tohoku Murata, QA-TR-91353)
    type: sds
    url: https://asset.conrad.com/media10/add/160267/c1/-/en/001086173SD00/sigurnosni-podatkovni-list-1086173-kamera-akumulator-sony-np-bx1-36-v-1240-mah-npbx1ce.pdf
    year: 2019
  - title: Lithium Nickel Dioxide safety data sheet (Stanford Advanced Materials)
    type: sds
    url: https://samaterials.com/tds/1697120088-lithium-nickel-dioxide-lno-powder-sds.pdf
    year: 2023
  - title: "Understanding how off-stoichiometry promotes cation mixing in LiNiO2 (arXiv preprint)"
    type: paper
    url: https://arxiv.org/abs/2401.05983
    year: 2024
  - title: "NIST Atomic Weights and Isotopic Compositions for All Elements"
    type: database
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl
    year: 2026
gaps:
  - 'Thermal runaway onset and heat release (DSC or ARC) for pure LiNiO2 in a cell: no sourced value found; the 1,460 J/g style figures in the NCA profile are for NCA, not LiNiO2.'
  - Lee et al. 2001 (J. Power Sources 97-98, 321) reports delithiated Li(1-x)NiO2 turning to spinel at 180 to 250 degC and to rock salt above 270 degC; seen only in a search summary, the paper could not be opened, so no value is entered.
  - 'Price, Allan and Slater (Energy Advances 2023) first-cycle capacities of 221 and 199 mAh/g for coprecipitated and solid-state LiNiO2: seen only in a search summary; the page returned HTTP 403, so no value is entered.'
  - 'Practical (delivered) capacity of undoped LiNiO2 with its voltage window and rate: no value from an opened source. The ijms-2026 review figure for NCA and NMC is not LNO.'
  - 'Electronic conductivity, crystallographic density, melting or decomposition temperature of the powder, and thermal conductivity: no sourced value found. The SDS from Stanford Advanced Materials states no physical properties in the text read.'
  - 'Volume change of the c-axis at the H2 to H3 transition for pure LiNiO2: no sourced percentage found (an ORNL neutron-diffraction paper and an OSTI report could not be opened).'
  - 'Whether the 27% ''lithium nickel oxide'' in the Sony pack is pure LiNiO2, an NCA, or an NMC: the sheet gives only the name and the LiNiO2 CAS number, so the exact composition is unknown.'
  - 'Space use: no sourced mission or flight use of LiNiO2 found. NCA and NMC profiles cover the nickel-rich layered oxides that NASA lists.'
  - 'Radiation, vacuum, and cold-temperature behaviour: no sourced data found.'
  - 'Harmonised EU classification of LiNiO2 (CLP Annex VI): the NextSDS page lists the substance (EC 620-400-4) but showed no classification text, so the harmonised class is not confirmed. ECHA C&L Inventory was not opened.'
sources:
  sony-sds:
    title: Safety Data Sheet, Lithium Ion Polymer Rechargeable Battery Pack NP-BX1 / SP94BPIN2C (Sony Corporation product, Tohoku Murata Manufacturing)
    id: QA-TR-91353
    url: https://asset.conrad.com/media10/add/160267/c1/-/en/001086173SD00/sigurnosni-podatkovni-list-1086173-kamera-akumulator-sony-np-bx1-36-v-1240-mah-npbx1ce.pdf
    year: 2019
    kind: datasheet
    license: manufacturer document, quoted facts only
  sa-sds:
    title: Safety Data Sheet, Lithium Nickel Dioxide (Stanford Advanced Materials)
    id: CAS 12031-65-1, revised 05/02/2023
    url: https://samaterials.com/tds/1697120088-lithium-nickel-dioxide-lno-powder-sds.pdf
    year: 2023
    kind: datasheet
    license: manufacturer document, quoted facts only
  pubchem-lno:
    title: PubChem compound record, Lithium nickel oxide (LiNiO2), CID 3035375
    id: CID 3035375
    url: https://pubchem.ncbi.nlm.nih.gov/compound/3035375
    year: 2026
    kind: database
    license: public domain (NCBI)
  cheng-2023:
    title: Mitigating the High-Charge Detrimental Phase Transformation in LiNiO2 Using Doping Engineering
    id: ACS Energy Lett. 2023, 8, 2401-2407, doi 10.1021/acsenergylett.3c00169
    url: https://doi.org/10.1021/acsenergylett.3c00169
    year: 2023
    kind: paper
    license: publisher PDF (author copy read), facts only
  komurcuoglu-2024:
    title: Understanding how off-stoichiometry promotes cation mixing in LiNiO2
    id: arXiv 2401.05983
    url: https://arxiv.org/abs/2401.05983
    year: 2024
    kind: paper
    license: arXiv preprint
  acta-b-2026:
    title: Unravelling superstructure and electronic ordering in LiNiO2 bulk single crystals grown by optical floating zone technique
    id: Acta Cryst. B 2026, 82, doi 10.1107/S2052520626001009
    url: https://doi.org/10.1107/S2052520626001009
    year: 2026
    kind: paper
    license: CC BY 4.0
  demuth-2025:
    title: In Situ 4D STEM of LiNiO2 Particles Heated in an Oxygen Atmosphere
    id: Small Methods 2025, doi 10.1002/smtd.202500357
    url: https://doi.org/10.1002/smtd.202500357
    year: 2025
    kind: paper
    license: CC BY 4.0
  ijms-2026:
    title: Nanostructured Cathode Materials for Rechargeable Lithium-Ion Batteries, Synthesis, Morphology, and Performance
    id: Int. J. Mol. Sci. 2026, 27, 6797, doi 10.3390/ijms27156797
    url: https://doi.org/10.3390/ijms27156797
    year: 2026
    kind: paper
    license: CC BY 4.0
  usgs-nickel-2026:
    title: Mineral Commodity Summaries 2026, Nickel
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    year: 2026
    kind: report
    license: public domain
  nist-atomic-weights:
    title: "NIST Atomic Weights and Isotopic Compositions for All Elements (standard atomic weight table)"
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl
    year: 2026
    kind: database
    license: public domain (US government work)
license: CC-BY-4.0
updated: '2026-10-17'
review:
  status: draft
  method: assistant
  checked_values: 15
  unreachable: 4
  caveats: 8
  note: Written by an AI assistant on 2026-10-17. Values were read in the text of the source PDFs, PubChem's data service, or the PMC full text. The 250 and 275 mAh/g theoretical capacities disagree between sources. The review figures (cycle retention, thermal-stability range, density) are second-hand. Four candidate sources could not be opened (Lee 2001, Price 2023, an ORNL paper, the PubChem web page) and are listed in gaps. No values were taken from memory.
story:
  recipe:
    line: "LiNiO2 is made by conventional solid-state synthesis, which leaves extra nickel on lithium sites, so the real composition is Li1-zNi1+zO2 (arXiv 2401.05983, Introduction and the Ni migration discussion). Synthesis temperatures and atmospheres were not read in this run."
    parts:
      - {name: Lithium, symbol: Li, atoms: 1, atomic_weight: 6.94, role: "The only element in the anode. NIST gives a range for natural abundance; 6.94 is the rounded value used in the LFP profile."}
      - {name: Nickel, symbol: Ni, atoms: 1, atomic_weight: 58.6934, role: "The transition metal that carries the charge. NIST gives 58.6934(4) for the natural element."}
      - {name: Oxygen, symbol: O, atoms: 2, atomic_weight: 15.999, role: "Two oxygen atoms per unit form the layered oxide framework. NIST gives a range for natural abundance"}
  risk_groups:
    - title: For people
      level: 3
      verdict: Classified as a suspected or proven carcinogen in the powder
      lead: The pure powder is classified more strictly than the finished battery, which Sony lists as not regulated.
      points:
        - label: The powder
          line: PubChem lists lithium nickel dioxide with signal word Danger and H317 (allergic skin reaction), H350i (may cause cancer by inhalation) and H372 (organ damage from repeated exposure). The ECHA notifications it aggregates give H317 in 100%, H350 in 99.4% and H372 in 100% of 163 reports. A supplier sheet from Stanford Advanced Materials is milder, listing H317 and H351 with signal word Warning, so the sources disagree.
        - label: Inside a battery
          line: The Sony NP-BX1 sheet lists the pack as not applicable for regulated class and says the cell contains no metallic lithium. It does warn that heat or leaking electrolyte can occur if terminals touch metal, and that the electrolyte is flammable.
        - label: Fumes
          line: The Sony sheet says vapor from burning batteries may irritate eyes, skin and throat, and that corrosive gas may form during fire fighting.
    - title: If it fails
      lead: Results come from a pack sheet and from laboratory and simulation studies of LiNiO2, not from failures of space hardware.
      points:
        - label: Hot pack
          line: The Sony sheet says external short-circuit, crush, or exposure of the pack to over 100 degC generates heat and ignites.
        - label: Heated in oxygen
          line: Thinned LiNiO2 particles heated in 1 bar oxygen began breaking down from the layered form toward a rock-salt form at about 350 degC. The authors note this is higher than in vacuum experiments.
        - label: High charge
          line: A first-principles study predicts that after 75% of the lithium is removed, the O3-to-O1 phase appears, which the paper links to cracking and oxygen loss.
    - title: Handling and storage
      points:
        - label: Sony pack
          line: Store at -10 to 30 degC, never at 60 degC or above, charge only at 0 to 45 degC, and do not open, short, crush or burn the pack.
        - label: Powder
          line: The supplier sheet says avoid breathing dust, wear protective gloves, store locked up and send waste to an approved disposal plant.
  why: 'Lithium nickel oxide (LiNiO2) is a layered oxide: sheets of nickel and oxygen with lithium ions between them, the same layout as lithium cobalt oxide but with nickel in place of cobalt. When a cell charges, lithium leaves the layers and the nickel gives up charge; when it discharges, lithium goes back in. A single-crystal study measured the cell of the 2 x 2 superstructure at a = 5.8247 and c = 14.271 Angstrom. LiNiO2 is the end member of the NCA and NMC families, which are made by replacing part of the nickel with cobalt, aluminium or manganese. In the review used here it has an average voltage of about 4 V, and theoretical capacities of 275 (one paper) or about 250 mAh/g (another) are quoted, so the sources disagree. The reason it is rarely used on its own is shown in the same papers: nickel ends up in lithium sites, the structure changes damagingly at high charge, and the oxide loses oxygen when heated. The Sony pack sheet below shows it in a real product mixed with lithium cobalt oxide.'
  uses:
    - where: Sony camera battery pack
      line: The Sony NP-BX1 safety data sheet (Tohoku Murata, 1 January 2019) describes a lithium ion polymer pack with one cell, 1240 mAh, 4.5 Wh, average 3.60 V. In its composition table lithium nickel oxide (CAS 12031-65-1) is 27% of the pack as active material, lithium cobalt oxide is 7%, and carbon is 28%.
    - where: Parent of NCA and NMC cathodes
      line: Cheng and co-workers describe LiNiO2 as the ultimate end member of the NCA and NMC families. NMC compositions moved from 33% nickel in NMC111 to 60% in NMC622 and 80% in NMC811.
    - where: Model material in research
      line: A computational paper treats LiNiO2 as a model for the atomic-scale behavior of cobalt-free nickel-rich cathodes. This is research use, not a flown or commercial cathode.
  can_do:
    - label: Capacity
      value: 275 mAh/g theoretical
      line: Cheng et al. state 275 mAh/g as the highest theoretical capacity in the NCA and NCM families. The ijms review quotes close to 250 mAh/g in one place and 275 in another, so use the figure with that caveat. No delivered capacity for undoped material from an opened source is in this record.
    - label: Voltage
      value: About 4 V
      line: A review gives an average operating voltage of approximately 4 V against lithium and an electrode density of about 3.3 g/cm3.
    - label: Structure
      value: R-3m layered
      line: Single-crystal X-ray refinement confirms the rhombohedral layered structure with alternating LiO6 and NiO6 octahedra, in a 2 x 2 superstructure with a = 5.8247 and c = 14.271 Angstrom at 300 K.
    - label: Cycling
      value: 69.2% after 100 cycles
      line: In a niobium-doping study quoted by a review, undoped LNO kept 69.2% of its capacity after 100 cycles at 0.5 C, against 91.4% for the doped version. The same review lists LNO as poor undoped, below 70% at 100 cycles.
    - label: Heat
      value: About 350 degC in oxygen
      line: Thinned LiNiO2 particles heated in 1 bar oxygen began to degrade toward rock salt at about 350 degC. A comparison table in the ijms review lists a thermal stability of 190 to 210 degC for LNO, but does not define it, so the two numbers cannot be compared directly.
  compare: 'LiNiO2 and lithium cobalt oxide share a layered structure. The ijms comparison table lists LCO at about 140 mAh/g and NCA at about 200 mAh/g in its Table 4. Its Table 5 lists thermal stability of about 200 degC for LCO, 190 to 210 for LNO, 210 to 230 for NCA and 250 to 300 for NMC333, without defining the figure. NCA and NMC keep most of the nickel and add other metals to fix its problems: Cheng et al. write that cobalt-rich NMC111 has 33% nickel while NMC811 has 80%. A review says LiNi0.5Mn0.5O2 has improved thermal stability and cycling performance compared with LiNiO2. The NCA and NMC profiles in this collection cover those blends in detail.'
  good_for:
    - A cobalt-free layered oxide with a high theoretical capacity (275 mAh/g in one paper).
    - 'Understanding nickel-rich cathodes: it is the model material for NCA and NMC behavior.'
  watch_out:
    - Nickel in lithium sites. Extra nickel in the Li layer blocks lithium paths and is hard to avoid in synthesis, so ideal material is difficult to make.
    - Poor cycling when undoped. One quoted study kept 69.2% after 100 cycles at 0.5 C.
    - Phase change at high charge. The O3-to-O1 phase is predicted after 75% of the lithium is removed.
    - Powder hazards. PubChem lists H350i and H372, a stricter classification than one supplier sheet gives.
  verdict: 'LiNiO2 is best understood as the parent of NCA and NMC rather than a cathode to choose on its own: high theoretical capacity, but hard to make ideal, short-lived undoped, and thermally touchy. Its place in the Sony pack, 27% by mass, shows it in use as part of a blend. There is no sourced space use for pure LiNiO2 here.'
  compare_rows:
    - label: Density
      benchmark: density
      scope: material
    - label: Avg voltage
      benchmark: avg_voltage
      scope: material
    - label: Theoretical capacity
      benchmark: theoretical_capacity
      scope: material