{
  "node": {
    "id": "term:olivine-structure",
    "type": "Term",
    "label": "Olivine structure",
    "properties": {
      "id": "olivine-structure",
      "name": "Olivine structure",
      "aka": [
        "LiMPO₄ structure",
        "phospho-olivine"
      ],
      "section": "topic-chemistries",
      "definition": "The orthorhombic structure of LiFePO₄ and its relatives, in which phosphate groups lock oxygen in place and lithium lies in one-dimensional channels. Strong phosphorus–oxygen bonds make the material thermally stable and long-lived, but one-dimensional diffusion and poor electronic conductivity call for small, carbon-coated particles. LMFP substitutes manganese to raise the voltage.",
      "related": [
        "lfp",
        "lmfp",
        "polyanionic-cathode",
        "spinel-structure",
        "layered-oxide",
        "particle-size"
      ],
      "url": "https://lemonergy.com/learn/glossary/olivine-structure/",
      "mentions": [
        "electronic-conductivity",
        "diffusion",
        "manganese"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:6093",
      "source": "term:olivine-structure",
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      "id": "edge:6094",
      "source": "term:olivine-structure",
      "target": "term:lfp",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6095",
      "source": "term:olivine-structure",
      "target": "term:lmfp",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6096",
      "source": "term:olivine-structure",
      "target": "term:polyanionic-cathode",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6097",
      "source": "term:olivine-structure",
      "target": "term:spinel-structure",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6098",
      "source": "term:olivine-structure",
      "target": "term:layered-oxide",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6099",
      "source": "term:olivine-structure",
      "target": "term:particle-size",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/olivine-structure/electronic-conductivity",
      "source": "term:olivine-structure",
      "target": "term:electronic-conductivity",
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        "field": "definition",
        "meaning": "Text mention; not a causal claim"
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    {
      "id": "edge:mentions/olivine-structure/diffusion",
      "source": "term:olivine-structure",
      "target": "term:diffusion",
      "type": "mentions",
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        "sourceFile": "terms.json",
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        "meaning": "Text mention; not a causal claim"
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      "source": "term:olivine-structure",
      "target": "term:manganese",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
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    {
      "id": "edge:6103",
      "source": "term:olivine-structure",
      "target": "reference:manthiram-cathodes",
      "type": "cites",
      "properties": {
        "sourceFile": "wiki-references.json",
        "scope": "direct technical reference"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-chemistries",
      "type": "Topic",
      "label": "Lithium-ion chemistries and cell formats",
      "properties": {
        "id": "topic-chemistries",
        "name": "Lithium-ion chemistries and cell formats",
        "lede": "The electrode materials that define a lithium-ion cell, the crystal structures behind them, and the shapes cells are built in.",
        "context": "Separate chemistry from form factor.",
        "example": "Two cylindrical cells can share dimensions yet differ in cathode, capacity and current limits.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/cell-architecture/",
        "lesson_label": "Open cell architecture"
      }
    },
    {
      "id": "term:lfp",
      "type": "Term",
      "label": "LFP",
      "properties": {
        "id": "lfp",
        "name": "LFP",
        "aka": [
          "lithium iron phosphate",
          "LiFePO₄"
        ],
        "section": "topic-chemistries",
        "definition": "A positive electrode material, LiFePO₄, giving cells a nominal voltage around 3.2 V, long cycle life and good thermal stability, but less energy per kilogram than nickel-rich oxides. Its flat voltage curve makes state of charge hard to read from voltage alone.",
        "related": [
          "cathode-active-material",
          "nmc",
          "lmfp",
          "ocv-soc-curve",
          "cycle-life"
        ],
        "lesson": "fundamentals/cell-anatomy/#voltage",
        "example": {
          "title": "Chemistry is not the whole datasheet",
          "text": "Two LFP products can differ in format, loading, capacity and current limits. Their cathode family alone does not make them interchangeable."
        },
        "url": "https://lemonergy.com/learn/glossary/lfp/",
        "mentions": [
          "electrode",
          "positive-electrode",
          "nominal-voltage",
          "discharge-curve",
          "state-of-charge"
        ]
      }
    },
    {
      "id": "term:lmfp",
      "type": "Term",
      "label": "LMFP",
      "properties": {
        "id": "lmfp",
        "name": "LMFP",
        "aka": [
          "lithium manganese iron phosphate"
        ],
        "section": "topic-chemistries",
        "definition": "Lithium iron phosphate with part of the iron replaced by manganese, which lifts the average voltage to about 3.8 V and so the energy density by 10–20 % while keeping most of LFP’s safety and cost advantages.",
        "related": [
          "lfp",
          "cathode-active-material",
          "energy-density"
        ],
        "url": "https://lemonergy.com/learn/glossary/lmfp/",
        "mentions": [
          "manganese"
        ]
      }
    },
    {
      "id": "term:polyanionic-cathode",
      "type": "Term",
      "label": "Polyanionic cathode",
      "properties": {
        "id": "polyanionic-cathode",
        "name": "Polyanionic cathode",
        "aka": [
          "polyanion cathode",
          "NVPF",
          "NFPP",
          "phosphate cathode"
        ],
        "section": "topic-other-chemistries",
        "definition": "A positive material built from transition metals and polyanion groups such as PO₄³⁻, SO₄²⁻ or P₂O₇⁴⁻. The strongly bonded groups raise the voltage through the inductive effect and hold oxygen tightly, giving long life and safety at some cost in capacity and conductivity. LFP is the lithium example; Na₃V₂(PO₄)₂F₃ and iron-based Na₄Fe₃(PO₄)₂P₂O₇ serve sodium-ion cells.",
        "related": [
          "lfp",
          "olivine-structure",
          "sodium-ion",
          "prussian-blue-analogue",
          "layered-oxide"
        ],
        "url": "https://lemonergy.com/learn/glossary/polyanionic-cathode/",
        "mentions": []
      }
    },
    {
      "id": "term:spinel-structure",
      "type": "Term",
      "label": "Spinel structure",
      "properties": {
        "id": "spinel-structure",
        "name": "Spinel structure",
        "aka": [
          "spinel crystal structure",
          "AB₂O₄ structure"
        ],
        "section": "topic-chemistries",
        "definition": "A cubic crystal structure of formula AB₂O₄ in which, for lithium materials, lithium sits in tetrahedral sites and transition metals in octahedral ones, leaving three-dimensional channels for lithium to move. That gives good rate capability; it is the framework of LMO, high-voltage LNMO and lithium titanate. Manganese spinels suffer manganese dissolution and Jahn–Teller distortion.",
        "related": [
          "lmo",
          "lnmo",
          "lto",
          "layered-oxide",
          "olivine-structure",
          "transition-metal-dissolution"
        ],
        "url": "https://lemonergy.com/learn/glossary/spinel-structure/",
        "mentions": [
          "rate-capability",
          "jahn-teller-distortion",
          "manganese"
        ]
      }
    },
    {
      "id": "term:layered-oxide",
      "type": "Term",
      "label": "Layered oxide",
      "properties": {
        "id": "layered-oxide",
        "name": "Layered oxide",
        "abbr": "LTMO",
        "aka": [
          "layered transition-metal oxide",
          "α-NaFeO₂ structure",
          "O3 structure",
          "P2 structure"
        ],
        "section": "topic-chemistries",
        "definition": "The crystal structure of LCO, NMC and NCA: close-packed oxygen layers with lithium and transition-metal ions in alternate layers of octahedral sites, so lithium moves in two-dimensional sheets. The structure offers high capacity and voltage but can distort or mix cations when deeply delithiated. Sodium versions are labelled O3 or P2 by their stacking.",
        "related": [
          "nmc",
          "lco",
          "nca",
          "structural-degradation",
          "spinel-structure",
          "sodium-ion"
        ],
        "url": "https://lemonergy.com/learn/glossary/layered-oxide/",
        "mentions": [
          "stacking"
        ]
      }
    },
    {
      "id": "term:particle-size",
      "type": "Term",
      "label": "Particle size",
      "properties": {
        "id": "particle-size",
        "name": "Particle size",
        "aka": [
          "D50"
        ],
        "section": "topic-transport",
        "definition": "The diameter of active-material particles, usually quoted as D50, the median, in micrometres. Small particles shorten the solid diffusion path and favour power; large ones pack densely and favour energy and stability.",
        "unit": "µm",
        "related": [
          "solid-state-diffusion",
          "specific-surface-area",
          "rate-capability",
          "single-crystal"
        ],
        "url": "https://lemonergy.com/learn/glossary/particle-size/",
        "mentions": [
          "diffusion"
        ]
      }
    },
    {
      "id": "term:electronic-conductivity",
      "type": "Term",
      "label": "Electronic conductivity",
      "properties": {
        "id": "electronic-conductivity",
        "name": "Electronic conductivity",
        "section": "topic-electrochemistry",
        "definition": "How readily a material conducts electrons. Current collectors and carbon additives supply it in an electrode because most active materials, LFP above all, conduct electrons poorly; a good electrolyte should have none, or it would self-discharge the cell.",
        "related": [
          "conductive-additive",
          "current-collector",
          "ionic-conductivity",
          "electronic-path"
        ],
        "url": "https://lemonergy.com/learn/glossary/electronic-conductivity/",
        "mentions": [
          "electrode",
          "electrolyte",
          "self-discharge"
        ]
      }
    },
    {
      "id": "term:diffusion",
      "type": "Term",
      "label": "Diffusion",
      "properties": {
        "id": "diffusion",
        "name": "Diffusion",
        "section": "topic-transport",
        "definition": "The net movement of a species from where it is concentrated to where it is scarce, driven by random thermal motion. In a cell lithium diffuses through the electrolyte in the pores and, far more slowly, through the solid particles themselves.",
        "related": [
          "ficks-first-law",
          "diffusion-coefficient",
          "solid-state-diffusion",
          "concentration-gradient",
          "migration"
        ],
        "lesson": "transport/ficks-first-law/#in-a-cell",
        "url": "https://lemonergy.com/learn/glossary/diffusion/",
        "mentions": [
          "electrolyte"
        ]
      }
    },
    {
      "id": "term:manganese",
      "type": "Term",
      "label": "Manganese",
      "properties": {
        "id": "manganese",
        "name": "Manganese",
        "aka": [
          "manganese sulfate",
          "high-purity manganese sulfate",
          "HPMSM"
        ],
        "section": "topic-sustainability",
        "definition": "A cheap, abundant metal used in NMC, LMO and LMFP positive electrodes and in alkaline cells. Ore comes mostly from South Africa, Gabon and Australia, but about 95 % of battery-grade high-purity manganese sulfate was refined in China in 2024, which puts manganese on critical-raw-material lists despite plentiful reserves.",
        "related": [
          "nmc",
          "lmo",
          "lmfp",
          "critical-raw-materials",
          "cobalt",
          "nickel-sulfate"
        ],
        "url": "https://lemonergy.com/learn/glossary/manganese/",
        "mentions": []
      }
    },
    {
      "id": "reference:manthiram-cathodes",
      "type": "Reference",
      "label": "A reflection on lithium-ion battery cathode chemistry",
      "properties": {
        "title": "A reflection on lithium-ion battery cathode chemistry",
        "publisher": "Nature Communications",
        "url": "https://doi.org/10.1038/s41467-020-15355-0",
        "type": "Review article",
        "scope": "Layered oxides, spinels and polyanion cathodes; links between composition, structure and performance.",
        "year": 2020,
        "authors": [
          "Arumugam Manthiram"
        ],
        "accessed": "2026-10-27"
      }
    }
  ]
}