spore: profile id: lithium-manganese-oxide spore_version: 0.2 family: lithium name: Lithium manganese oxide (spinel), with the high-voltage nickel variant LNMO abbreviation: LMO role: cathode category: energy type: li-ion-cathodes summary: | LMO (LiMn2O4) is a cubic spinel cathode: manganese and oxygen form a three-dimensional framework through which lithium moves. It is cobalt-free and uses abundant manganese, but it stores less charge per gram than the layered oxides and its capacity fades. The fade has measured causes: manganese dissolves from the spinel, cracks form in the particles, and the material undergoes an irreversible phase change. A high-voltage relative, LiNi0.5Mn1.5O4 (LNMO), works near 4.7 V but has its own dissolution and high-temperature problems. This profile covers both, with the LNMO values labelled as such. best_for: Cobalt-free, low-cost cathodes where a manganese spinel is blended with a layered oxide (a 2024 lab study tested this blend) weakest_at: 'Capacity fade: manganese dissolution, cracking and an irreversible phase change in the cathode (sources in corrosion and failure risks)' identity: formula: LiMn2O4 (spinel); high-voltage variant LiNi0.5Mn1.5O4 (LNMO) cas: 12057-17-9 crystal_system: cubic (spinel) space_group: Fd-3m source: nc-lmo-2019 where: Results, XRD refinement (spinel with Fd-3m symmetry, cubic cell parameter a = c = 8.24 A); CAS from the SAMaterials SDS, Section 3 (composition table); LNMO Fd3m from adv-sci-lnmo-2025 (space-group discussion) tags: environments: [] stresses: [] applications: - batteries properties: - benchmark: theoretical_capacity value: 285 unit: mAh/g scope: material conditions: basis: figure the paper gives for the full two-plateau capacity of the spinel; the same paper says commercial use is limited to the 4 V range, which provides only half of it method: Value stated in the paper's introduction, not recomputed here status: calculated note: The commonly quoted 148 mAh/g for the 4 V (one-electron) window appeared only in search results (a patent and a conference paper), which were not opened in this run, so it is not used. source: ceder-spinel-2023 where: Introduction, first page (paragraph beginning 'While its theoretical capacity') - benchmark: practical_capacity value: 123 unit: mAh/g scope: material conditions: rate: 0.1 C electrode: LiMn2O4 made from Mn3O4 and Li2CO3 by solid-state reaction (lab material) cell: half cell against lithium window: 3.4 to 4.3 V vs Li/Li+, as stated in the Methods for the half cells method: Reversible capacity read from the charge-discharge curves at 0.1 C, as written in the Results text status: ground note: A single lab material from one synthesis route, not a commercial powder value. The same paper gives 117 mAh/g for a lithium-rich variant. source: nc-lmo-2019 where: Results, first paragraph on charge-discharge curves (0.1 C); Methods (half-cell cycling) - benchmark: plateau_voltage label: Two sharp dQ/dV peaks of LiMn2O4 on charge value: 4.05 value_high: 4.15 bound: range unit: V vs Li/Li+ scope: material conditions: electrode: LiMn2O4 half cell, differential capacity plot basis: peak positions of dQ/dV on charge method: Peak positions as printed in the Results text (the plot is in the Supplementary Figure 2b) status: ground source: nc-lmo-2019 where: Results, paragraph on the dQ/dV plot (Supplementary Fig. 2b) - benchmark: plateau_voltage label: Two-phase plateau near 3 V (lithium-rich Li2Mn2O4 phase) value: 3 unit: V scope: material conditions: basis: two-phase reaction between LiMn2O4 and Li2Mn2O4, which the paper says occurs at about 3 V method: Value stated in the paper's introduction status: ground note: Approximate value as printed (about 3 V); the paper says commercial use is limited to the 4 V range, which leaves out the 3 V step. source: ceder-spinel-2023 where: Abstract and Introduction (paragraph on the two-phase reaction at about 3 V) - benchmark: volume_change value: 16 unit: '%' scope: material conditions: basis: anisotropic volume change from cubic LiMn2O4 (a = c = 8.24 A) to tetragonal Li2Mn2O4 (a = 8.01 A, c = 9.27 A) direction: on lithium insertion to Li2Mn2O4 method: Value printed in the paper's Results text status: ground source: nc-lmo-2019 where: Results, paragraph on the phase transition to tetragonal Li2Mn2O4 - benchmark: lattice_parameter label: Cubic cell parameter of LiMn2O4 (a = c) value: 8.24 unit: A scope: material conditions: phase: cubic LiMn2O4 spinel, room temperature XRD refinement as printed in the paper method: Value printed in the Results text status: ground note: Non-canonical benchmark name, used because no canonical lattice-parameter name fits. source: nc-lmo-2019 where: Results, paragraph on the phase transition (cubic LiMn2O4 cell parameter) - benchmark: plateau_voltage label: High-voltage plateau of LNMO (Ni2+/Ni4+ redox) value: 4.7 unit: V vs Li scope: material conditions: electrode: LiNi0.5Mn1.5O4 spinel basis: plateau printed as about 4.7 V vs Li method: Value stated in the review abstract and Section 2, printed as approximately 4.7 V status: ground note: This is the LNMO variant, not LMO. The printed value is approximate (about 4.7 V). source: adv-sci-lnmo-2025 where: Abstract; discussion of the 4.7 V plateau (Ni2+/Ni4+ redox) - benchmark: theoretical_energy_density label: Theoretical energy density of LNMO value: 650 unit: Wh/kg scope: material conditions: material: LiNi0.5Mn1.5O4 (LNMO) basis: stated as the theoretical energy density in the review abstract method: Value stated in the review abstract, not recomputed here status: calculated note: Non-canonical benchmark name. The printed value is approximate (about 650 Wh/kg). source: adv-sci-lnmo-2025 where: Abstract - benchmark: ion_migration_barrier label: Manganese ion migration barrier in LNMO with oxygen vacancies value: 0.2 unit: eV scope: material conditions: species: Mn ion on tetrahedral sites next to an oxygen vacancy basis: barrier quoted for Mn migration, compared with about 0.5 eV for Li diffusion in the same review method: Value quoted in the review from earlier calculation work, not measured here status: calculated note: Non-canonical benchmark name. The review cites a calculation study for this value and does not give its method in the text read. source: adv-sci-lnmo-2025 where: Discussion of oxygen vacancies and Mn migration (Figure 5d) corrosion: - environment: Charged spinel during cycling in a carbonate electrolyte headline: Manganese dissolves from LiMn2O4 and, with cracks and phase change, drives capacity fade. effect: The paper describes a cycle in which structural transformations accelerate manganese dissolution, and the dissolution feeds further damage. Cracks reach more than 100 nm into the particles after only 25 cycles. Dissolved manganese is deposited on the anode, but the authors measured far less dissolution than the electrochemical capacity loss, so dissolution alone does not explain the fade. rating: moderate conditions: cell: LiMn2O4 half and full cells observation: cracks in particles after 25 cycles; manganese found on the anode by ICP-AES and synchrotron XRF source: nc-lmo-2019 where: Results, Mn dissolution and anode deposition; Figure 3 (cracking after 25 cycles) - environment: Irreversible phase change on cycling (LiMn2O4 to Li2Mn2O4 and Li4Mn5O12) headline: The stoichiometric spinel suffers a severe, irreversible phase change on cycling. effect: Mn(III) disproportionation on charge gives Mn3O4 and a Li4Mn5O12-type phase, and over-lithiated Li2Mn2O4 forms on discharge. The paper says these transformations are irreversible, and calls the stoichiometric LiMn2O4 severely affected. The cubic-to-tetragonal change is a 16% volume change. rating: severe conditions: voltage: charging to 4.3 V in the half cells; 3.4 V at full discharge evidence: in situ and ex situ XRD, with Li4Mn5O12 peaks found in the charged electrode source: nc-lmo-2019 where: Results (in situ XRD and phase identification); Conclusions - environment: HF from LiPF6 electrolyte decomposition headline: HF from the electrolyte attacks the spinel lattice and helps form oxygen vacancies. effect: The review says HF formed when LiPF6 decomposes attacks LNMO and destabilizes the crystal lattice, and that this indirectly makes oxygen vacancies. It describes this for the high-voltage spinel, and notes that the Jahn-Teller effect adds lattice stress on charge and discharge. rating: moderate conditions: electrolyte: LiPF6 in carbonate solvents variant: LNMO; general statement, no rate given source: adv-sci-lnmo-2025 where: Discussion of electrolyte side reactions and oxygen vacancies - environment: High temperature in a lithium-ion cell (manganese deposition on the anode) headline: Manganese dissolution speeds up at high temperature and degrades the anode side too. effect: 'The review reports the manganese dissolution-migration-deposition model: Mn(2+) dissolved from the cathode builds up in the anode SEI, which raises impedance. The review says rising temperature speeds this process and gives poor performance at high temperature. It gives no rate figure for LMO.' rating: moderate conditions: basis: general statement on manganese-based cathodes; no LMO-specific temperature test in the text read source: adv-sci-lnmo-2025 where: Mn dissolution-migration-deposition model (Figure 3b) - environment: Powder in humid air headline: No measured humidity effect on the LMO powder was found. effect: The sources read do not test humidity exposure of LiMn2O4. The SDS sources give storage advice only. rating: unknown conditions: source_type: supplier SDS storage instruction source: sam-lmo-sds-2025 where: 'Section 7 (storage: keep containers tightly closed in a dry, cool, well-ventilated place)' risks: hazards: - text: The SAMaterials safety data sheet (revised 24 December 2025) says the product is not considered hazardous under the OSHA Hazard Communication Standard 2024, and gives no GHS label elements. ghs: [] source: sam-lmo-sds-2025 where: Section 2 (hazard identification) - text: A second supplier safety data sheet for lithium manganese oxide (revised February 2018) classifies it as not a hazardous substance or mixture under OSHA HCS, with no GHS label elements. ghs: [] source: mti-lmo-sds-2018 where: Section 2 (hazards identification, GHS classification) failure_risks: - mode: Capacity fade through manganese loss and cracking trigger: Cycling a LiMn2O4 cell, especially at higher temperature consequence: Cracks extend more than 100 nm into the particles after 25 cycles, and dissolved manganese deposits on the anode, which raises impedance and cuts capacity. severity: moderate source: nc-lmo-2019 where: Results (cracking and Mn deposition on the anode) - mode: Phase change in the 3 V region trigger: Discharge into the approximately 3 V two-phase region (Li2Mn2O4 formation) consequence: The 3 V transition is associated with a large, inhomogeneous volume change. Commercial use has been limited to the 4 V range, which provides only half the theoretical capacity. severity: moderate source: ceder-spinel-2023 where: Abstract; Introduction side_effects: - text: Mn(2+) that dissolves from the cathode builds up in the anode SEI, which hinders lithium diffusion and raises the negative electrode impedance. affects: Negative electrode of the same cell source: adv-sci-lnmo-2025 where: Mn dissolution-migration-deposition model (Figure 3b) handling: - text: The SDS for the powder says to avoid dust formation, to keep containers tightly closed in a dry, cool, well-ventilated place, and to keep the powder away from incompatible materials. The incompatible material it lists is an oxidizing agent. source: sam-lmo-sds-2025 where: Sections 7 and 10 (handling, storage and incompatible materials) mitigations: - text: Cation disorder (Mn moved onto the 16c sites) shortens the two-phase 3 V transition and removes it at the disorder level studied in the calculations. source: ceder-spinel-2023 where: Abstract and Results (cation disorder and the 3 V plateau) - text: Surface cladding, for example an alumina layer, inhibits HF-driven erosion of the high-voltage spinel in the cited studies. source: adv-sci-lnmo-2025 where: Discussion of surface coating and HF erosion uses: - application: batteries device: Blended positive electrode in laboratory lithium-ion cells (LiMn2O4 with LiNi0.5Mn0.3Co0.2O2) example: The 2024 operando study says blending gives an overall rate-capability gain for specific blend compositions, and that the effective current load on each component differs from the nominal applied rate. source: uab-lmo-nmc-2024 where: Highlights and abstract - application: batteries device: High-voltage cobalt-free cathode in research cells (LNMO) example: A 2025 review describes LNMO as a cobalt-free cathode with a high operating voltage platform near 4.7 V vs Li and a high theoretical energy density of about 650 Wh/kg, and notes poor cycling and rate performance. source: adv-sci-lnmo-2025 where: Abstract supply: - subject: Manganese abundance: The LNMO review gives a crustal abundance of 950 ppm for manganese, compared with 84 ppm for nickel and 25 ppm for cobalt. It gives no primary citation for these figures in the text read. producers: - country: South Africa share_percent: 38 year: 2025 - country: Gabon share_percent: 25 year: 2025 - country: Ghana share_percent: 10 year: 2025 - country: Australia share_percent: 8 year: 2025 - country: Brazil share_percent: 4 year: 2025 critical_lists: - list: USGS 2025 List of Critical Minerals (as summarised in CRS IF13145) listed: true recycling: 'USGS: manganese was recycled incidentally as a constituent of ferrous and nonferrous scrap, and scrap recovery specifically for manganese was negligible.' substitutes: - 'USGS: manganese has no satisfactory substitute in its major applications.' source: usgs-mcs2026-manganese where: World Mine Production and Reserves table (2025e, manganese content; shares calculated by Space Mushroom against the 20000 thousand t world total); Recycling; Substitutes - subject: Nickel (LNMO only) abundance: See the manganese entry; the LNMO review gives 84 ppm for nickel in the crust. producers: - country: Indonesia share_percent: 66.7 year: 2025 - country: Philippines share_percent: 6.9 year: 2025 - country: Russia share_percent: 5.1 year: 2025 - country: New Caledonia share_percent: 3.6 year: 2025 critical_lists: - list: USGS 2025 List of Critical Minerals (as summarised in CRS IF13145) listed: true recycling: 'USGS: most secondary nickel is from stainless-steel scrap; in 2025 nickel recovered from scrap accounted for about 60% of apparent consumption.' substitutes: - 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in construction.' source: usgs-mcs2026-nickel where: World Mine Production and Reserves table (2025e, shares calculated by Space Mushroom against the 3900000 t world total, rounded); Recycling; Substitutes media: [] documents: - title: 'SAMaterials safety data sheet: Lithium manganese(III,IV) oxide (LiMn2O4, CAS 12057-17-9), revised 24 December 2025' type: sds url: https://www.samaterials.com/tds/sc/1780480050-ST0869.pdf year: 2025 - title: Lithium Manganese Oxide safety data sheet (LiMn2O4, CAS 12057-17-9), revision February 2018 type: sds url: https://orgchemboulder.com/SDS/Lithium%20manganese%20oxide;%2012057-17-9.pdf year: 2018 - title: Correlation between manganese dissolution and dynamic phase stability in spinel-based lithium-ion battery (open access, Nature Communications) type: paper url: https://pmc.ncbi.nlm.nih.gov/articles/PMC6797712/ year: 2019 - title: Progress on the Attenuation Mechanism and Modification of the Cobalt-Free Spinel LiNi0.5Mn1.5O4 (open access, Advanced Science) type: paper url: https://pmc.ncbi.nlm.nih.gov/articles/PMC12442621/ year: 2025 - title: Removing the Two-Phase Transition in Spinel LiMn2O4 through Cation Disorder (ACS Energy Letters) type: paper url: https://doi.org/10.1021/acsenergylett.2c02141 year: 2023 - title: Towards understanding the functional mechanism and synergistic effects of LiMn2O4 - LiNi0.5Mn0.3Co0.2O2 blended positive electrodes (open access, Journal of Power Sources) type: paper url: https://doi.org/10.1016/j.jpowsour.2023.233804 year: 2024 - title: 'USGS Mineral Commodity Summaries 2026: Manganese' type: report url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf year: 2026 - title: 'USGS Mineral Commodity Summaries 2026: Nickel' type: report url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf year: 2026 - title: 'PubChem: LiMn2O4 (CID 23696272), formula and molecular weight' type: database url: https://pubchem.ncbi.nlm.nih.gov/compound/23696272 year: 2026 gaps: - 'No thermal-runaway or self-heating result for an LMO cell was read in this run. The Lei et al. 2017 MDPI paper (doi 10.3390/batteries3020014) that compares LMO, LFP and NMC cells could not be fetched: the publisher returned Access Denied to curl. The LFP profile cites that paper for an LMO onset of about 90 degC, which is not verified here.' - No theoretical capacity of 148 mAh/g for the 4 V window was verified from a fetched open source; the 285 mAh/g full-range value from ACS Energy Letters is used instead. - No LMO or LNMO density (crystallographic or tap) was found in a source read in this run. - No LNMO practical capacity typical value (lab or commercial) was found in the review text read; only individual doped-material examples in its tables, which are not used. - No flight, vacuum, radiation or thermal-vacuum test results for LMO or LNMO were found. - No open source for a commercial electric-vehicle or power-tool use of LMO was found in this run. The only use examples are a laboratory blend study and the LNMO review. - Humidity and atmospheric exposure of LMO powder is not measured in any source read. - Nickel hazards for LNMO (a nickel compound) have no source read in this run; the LMO hazards come from two SDSs that say the powder is not hazardous under OSHA HCS. - The ACGIH and Mexico exposure limits in the SAMaterials SDS table are ambiguous (two rows for the same compound), so no limit is stated. - EU critical raw materials status of manganese was not checked in this run. - 'Benchmark names not in the canonical list: volume_change, lattice_parameter, theoretical_energy_density and ion_migration_barrier.' - 'Properties are short of the 12-property target: nine numeric values could be read from pages fetched in this run.' - The ACS Energy Letters licence was not stated in the copy read; the values were checked against a PDF copy of the same paper hosted by Berkeley. sources: ceder-spinel-2023: title: Removing the Two-Phase Transition in Spinel LiMn2O4 through Cation Disorder id: doi:10.1021/acsenergylett.2c02141 (ACS Energy Letters 8, 314-319) url: https://ceder.berkeley.edu/publications/2022_Tina_Two-phase_spinel.pdf year: 2023 kind: paper license: not stated in the copy read nc-lmo-2019: title: Correlation between manganese dissolution and dynamic phase stability in spinel-based lithium-ion battery id: doi:10.1038/s41467-019-12626-3 (Nature Communications 10, PMC6797712) url: https://pmc.ncbi.nlm.nih.gov/articles/PMC6797712/ year: 2019 kind: paper license: CC BY 4.0 adv-sci-lnmo-2025: title: Progress on the Attenuation Mechanism and Modification of the Cobalt-Free Spinel LiNi0.5Mn1.5O4 id: doi:10.1002/advs.202508121 (Advanced Science 12, e08121, PMC12442621) url: https://pmc.ncbi.nlm.nih.gov/articles/PMC12442621/ year: 2025 kind: paper license: CC BY 4.0 uab-lmo-nmc-2024: title: Towards understanding the functional mechanism and synergistic effects of LiMn2O4 - LiNi0.5Mn0.3Co0.2O2 blended positive electrodes for Lithium-ion batteries id: doi:10.1016/j.jpowsour.2023.233804 (Journal of Power Sources 591, 233804) url: https://doi.org/10.1016/j.jpowsour.2023.233804 year: 2024 kind: paper license: CC BY-NC-ND 4.0 (as printed on the article) sam-lmo-sds-2025: title: 'Safety Data Sheet: Lithium manganese(III,IV) oxide, SAMaterials, revised 24 December 2025' id: CAS 12057-17-9 url: https://www.samaterials.com/tds/sc/1780480050-ST0869.pdf year: 2025 kind: datasheet license: supplier document, cited for facts only mti-lmo-sds-2018: title: Lithium Manganese Oxide safety data sheet, revision February 2018 id: CAS 12057-17-9 url: https://orgchemboulder.com/SDS/Lithium%20manganese%20oxide;%2012057-17-9.pdf year: 2018 kind: datasheet license: supplier document, cited for facts only pubchem-lmo: title: PubChem compound record, LiMn2O4 (CID 23696272) id: CID 23696272 url: https://pubchem.ncbi.nlm.nih.gov/compound/23696272 year: 2026 kind: database license: public domain (NCBI) nist-li-weight: title: NIST Atomic Weights and Isotopic Compositions for Lithium id: NIST standard atomic weight, lithium, interval 6.938 to 6.997 url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Li&ascii=html&isotype=some year: 2026 kind: database license: public domain (NIST) nist-o-weight: title: NIST Atomic Weights and Isotopic Compositions for Oxygen id: NIST standard atomic weight, oxygen, interval 15.999 03 to 15.999 77 url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=O&ascii=html&isotype=some year: 2026 kind: database license: public domain (NIST) usgs-mcs2026-manganese: title: 'Mineral Commodity Summaries 2026: Manganese' id: USGS MCS 2026, February 2026 url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf year: 2026 kind: report license: public domain (USGS) usgs-mcs2026-nickel: title: 'Mineral Commodity Summaries 2026: Nickel' id: USGS MCS 2026, February 2026 url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf year: 2026 kind: report license: public domain (USGS) crs-usgs-list-2026: title: U.S. Geological Survey's Critical Minerals List (CRS In Focus IF13145), summarising the Final 2025 List of Critical Minerals id: CRS IF13145 url: https://www.everycrsreport.com/reports/IF13145.html year: 2026 kind: report license: public domain (Congressional Research Service) license: CC-BY-4.0 updated: '2026-10-26' review: status: draft method: assistant checked_values: 9 unreachable: 0 caveats: 4 note: Written by an AI assistant on 2026-10-26 from pages read in this run. Nine numeric values, all found in the cited text by verify-values; the Lei et al. 2017 paper could not be opened. story: recipe: line: LiMn2O4 is a lithium manganese oxide with a cubic spinel structure. Each formula unit combines one lithium ion, two manganese atoms and four oxygen atoms, and the manganese is mixed between the +3 and +4 oxidation states. The high-voltage variant LiNi0.5Mn1.5O4 replaces part of the manganese with nickel. Lab material is made by a solid-state reaction of Mn3O4 and Li2CO3, ball-milled for 6 hours. parts: - name: Lithium symbol: Li atoms: 1 atomic_weight: 6.94 role: The mobile species. Lithium ions move through the spinel framework on charge and discharge. The NIST interval is 6.938 to 6.997; 6.94 is used here. - name: Manganese symbol: Mn atoms: 2 atomic_weight: 54.94 role: The redox centre. Mn(III) and Mn(IV) carry the charge; the Mn(III) disproportionation on charge drives the phase change. - name: Oxygen symbol: O atoms: 4 atomic_weight: 15.999 role: Forms the close-packed oxygen framework that holds the spinel together. Oxygen vacancies form at high voltage in the LNMO variant. risk_groups: - title: For people level: 1 verdict: Not classified hazardous under OSHA lead: Both supplier safety data sheets classify lithium manganese oxide powder as not hazardous under the US hazard communication standard. Dust should still be avoided. points: - label: The powder line: The SAMaterials SDS (revised December 2025) and the second SDS (revised February 2018) both say the product is not hazardous and carries no GHS label elements. - label: Dust line: Both sheets advise avoiding dust formation, and the SAMaterials sheet lists an exposure guideline for the compound. - label: Oxidizer line: The SAMaterials sheet lists oxidizing agents as incompatible. - title: Inside the cell lead: These results come from laboratory cells, not from field incidents or heating tests on LMO cells. points: - label: Manganese loss line: Manganese dissolves from the spinel and deposits on the anode, which raises impedance. Dissolution alone does not account for the measured capacity loss. - label: Cracks and phase change line: Cracks reach more than 100 nm into the particles within 25 cycles. The stoichiometric spinel shows an irreversible phase change that the authors call severe. - label: Acid from the electrolyte line: Hydrofluoric acid, formed when the LiPF6 electrolyte decomposes, attacks the high-voltage spinel and helps form oxygen vacancies. - title: Handling and storage points: - label: Storage line: Keep the container tightly closed in a dry, cool, well-ventilated place, away from oxidizing agents. - label: Dust line: Avoid dust formation during handling. why: 'Lithium manganese oxide (LMO, LiMn2O4) is a spinel cathode for lithium-ion cells. Its framework is cubic, and manganese is cheap and abundant, with no cobalt. It stores less charge per gram than the layered oxides. Its main problem is capacity fade: manganese dissolves, the particles crack, and the spinel undergoes a phase change that is irreversible on cycling. The high-voltage relative LNMO works near 4.7 V and has better energy density in theory, but it shares the dissolution and high-temperature problems. Both are chosen for their low cost and cobalt-free chemistry rather than for long life.' uses: - where: Blends with layered cathodes line: A 2024 open-access laboratory study tested LiMn2O4 blended with LiNi0.5Mn0.3Co0.2O2. The authors found an overall rate-capability gain for specific blend compositions, and they note the effective current on each component differs from the nominal rate. - where: High-voltage cobalt-free cathode (LNMO) line: A 2025 review describes LNMO as a cobalt-free cathode with a plateau near 4.7 V against lithium and a high theoretical energy density of about 650 Wh/kg. It also notes poor cycling and rate performance. can_do: - label: Capacity benchmark: practical_capacity value: 123 mAh/g line: In a laboratory half cell at 0.1 C, a LiMn2O4 sample gave a reversible capacity of 123 mAh/g. The theoretical value for the full two-plateau range is 285 mAh/g, but commercial use is limited to the 4 V range, which gives only half of that. - label: Voltage value: 4.05 to 4.15 V line: Charge curves of LiMn2O4 show two sharp dQ/dV peaks at 4.05 and 4.15 V against lithium. A separate two-phase reaction near 3 V (Li2Mn2O4) gives a second step, which is lost in commercial 4 V use. - label: High-voltage variant value: About 4.7 V line: LNMO works at about 4.7 V against lithium, from the Ni2+/Ni4+ redox couple. Its theoretical energy density is about 650 Wh/kg, as stated in the review. compare: 'LMO sits at the low-cost, cobalt-free end of the cathode family. It stores less charge per gram than the layered oxides in practice and has a lower voltage on its main plateau. Its fade is well documented: manganese dissolution, cracking and an irreversible phase change. LNMO works at about 4.7 V, but it brings more electrolyte breakdown and more manganese and nickel dissolution. The table compares the LMO capacity and voltage with the other cathodes in the collection.' compare_rows: - label: Ideal energy per gram benchmark: theoretical_capacity scope: material - label: Energy per gram in a lab test benchmark: practical_capacity scope: material - label: Voltage benchmark: plateau_voltage scope: material handling: - The SDS says to avoid dust, keep the container closed in a dry place, and keep it away from oxidizing agents. - Wear gloves and appropriate protective clothing to prevent skin contact. good_for: - Cobalt-free, low-cost cathode chemistry. The 2024 study showed a rate gain when LMO is blended with a layered cathode. - 'High-voltage research: LNMO works near 4.7 V, the high-voltage member of the spinel family.' watch_out: - Capacity fade. The stoichiometric spinel shows an irreversible phase change on cycling, and cracks form within 25 cycles in the lab cells studied. - Only half the theoretical capacity is available in the commercial 4 V range. - Manganese dissolution and HF attack become worse at high temperature, according to the review. verdict: LMO is the low-cost, cobalt-free choice that buys its cost with capacity fade. It is most useful as a blend component with a layered cathode, and LNMO extends its voltage at the cost of more electrolyte breakdown.