{
  "node": {
    "id": "term:gitt",
    "type": "Term",
    "label": "Galvanostatic intermittent titration technique",
    "properties": {
      "id": "gitt",
      "name": "Galvanostatic intermittent titration technique",
      "abbr": "GITT",
      "section": "topic-testing",
      "definition": "A series of short constant-current pulses each followed by a long rest, so that both the equilibrium voltage curve and the solid diffusion coefficient can be extracted at each state of charge. It is slow, often days per cell, and a staple of parameterisation.",
      "related": [
        "diffusion-coefficient",
        "open-circuit-voltage",
        "parameterisation",
        "pitt",
        "intermittent-current-interruption"
      ],
      "url": "https://lemonergy.com/learn/glossary/gitt/",
      "mentions": [
        "discharge-curve",
        "state-of-charge",
        "diffusion"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:2671",
      "source": "term:gitt",
      "target": "topic:topic-testing",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:2672",
      "source": "term:gitt",
      "target": "term:diffusion-coefficient",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2673",
      "source": "term:gitt",
      "target": "term:open-circuit-voltage",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2674",
      "source": "term:gitt",
      "target": "term:parameterisation",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2675",
      "source": "term:gitt",
      "target": "term:pitt",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2676",
      "source": "term:gitt",
      "target": "term:intermittent-current-interruption",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/gitt/discharge-curve",
      "source": "term:gitt",
      "target": "term:discharge-curve",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/gitt/state-of-charge",
      "source": "term:gitt",
      "target": "term:state-of-charge",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/gitt/diffusion",
      "source": "term:gitt",
      "target": "term:diffusion",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-testing",
      "type": "Topic",
      "label": "Testing methods",
      "properties": {
        "id": "topic-testing",
        "name": "Testing methods",
        "lede": "The measurements and test procedures that characterise a cell or pack, from capacity and pulse tests to abuse and environmental tests.",
        "context": "Record specimen, state, instrument, temperature and timing.",
        "example": "Resistance immediately after a current step can differ from a ten-second value because slower polarization contributes.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/",
        "lesson_label": "Open capacity measurements"
      }
    },
    {
      "id": "term:diffusion-coefficient",
      "type": "Term",
      "label": "Diffusion coefficient",
      "properties": {
        "id": "diffusion-coefficient",
        "name": "Diffusion coefficient",
        "abbr": "D",
        "aka": [
          "diffusivity"
        ],
        "section": "topic-transport",
        "definition": "The proportionality constant D in Fick’s first law, in m²/s. It sets how fast a species spreads for a given concentration gradient.",
        "unit": "m²/s",
        "related": [
          "ficks-first-law",
          "solid-state-diffusion",
          "gitt",
          "diffusion"
        ],
        "lesson": "transport/ficks-first-law/#law",
        "url": "https://lemonergy.com/learn/glossary/diffusion-coefficient/",
        "mentions": [
          "concentration-gradient"
        ]
      }
    },
    {
      "id": "term:open-circuit-voltage",
      "type": "Term",
      "label": "Open-circuit voltage",
      "properties": {
        "id": "open-circuit-voltage",
        "name": "Open-circuit voltage",
        "abbr": "OCV",
        "section": "topic-state",
        "definition": "The voltage across a cell’s terminals when no current flows and the cell has rested long enough for the voltage to settle. It depends on state of charge and temperature, and a cell whose open-circuit voltage falls unusually fast in storage may have an internal short.",
        "unit": "V",
        "related": [
          "ocv-soc-curve",
          "relaxation",
          "voltage-hysteresis",
          "k-value",
          "internal-short-circuit"
        ],
        "lesson": "fundamentals/cell-production/#finishing",
        "url": "https://lemonergy.com/learn/glossary/open-circuit-voltage/",
        "mentions": [
          "state-of-charge"
        ]
      }
    },
    {
      "id": "term:parameterisation",
      "type": "Term",
      "label": "Parameterisation",
      "properties": {
        "id": "parameterisation",
        "name": "Parameterisation",
        "aka": [
          "parameter identification"
        ],
        "section": "topic-transport",
        "definition": "Measuring or fitting the numbers a model needs: OCV curves, diffusion coefficients, exchange current densities, thicknesses and porosities for a physics model, or resistances and time constants for a circuit model. It is usually most of the modelling effort.",
        "related": [
          "newman-model",
          "equivalent-circuit-model",
          "gitt",
          "hppc",
          "electrochemical-impedance-spectroscopy"
        ],
        "url": "https://lemonergy.com/learn/glossary/parameterisation/",
        "mentions": [
          "open-circuit-voltage",
          "diffusion"
        ]
      }
    },
    {
      "id": "term:pitt",
      "type": "Term",
      "label": "Potentiostatic intermittent titration technique",
      "properties": {
        "id": "pitt",
        "name": "Potentiostatic intermittent titration technique",
        "abbr": "PITT",
        "section": "topic-testing",
        "definition": "The voltage-step counterpart of GITT: the potential is stepped and the decaying current recorded, giving the diffusion coefficient from the current transient. It needs a potentiostat rather than a cycler.",
        "related": [
          "gitt",
          "diffusion-coefficient",
          "potentiostat"
        ],
        "url": "https://lemonergy.com/learn/glossary/pitt/",
        "mentions": [
          "diffusion"
        ]
      }
    },
    {
      "id": "term:intermittent-current-interruption",
      "type": "Term",
      "label": "Intermittent current interruption",
      "properties": {
        "id": "intermittent-current-interruption",
        "name": "Intermittent current interruption",
        "abbr": "ICI",
        "aka": [
          "current interruption method"
        ],
        "section": "topic-testing",
        "definition": "Pausing the current for a few seconds every few minutes during a slow constant-current cycle and fitting the voltage response against the square root of time. The instant jump gives internal resistance and the slope a diffusion resistance, mapped across the whole state-of-charge range in a single cycle — a fast alternative to GITT.",
        "related": [
          "gitt",
          "internal-resistance",
          "diffusion-coefficient",
          "warburg-impedance",
          "dcir"
        ],
        "url": "https://lemonergy.com/learn/glossary/intermittent-current-interruption/",
        "mentions": [
          "diffusion"
        ]
      }
    },
    {
      "id": "term:discharge-curve",
      "type": "Term",
      "label": "Discharge curve",
      "properties": {
        "id": "discharge-curve",
        "name": "Discharge curve",
        "aka": [
          "voltage curve"
        ],
        "section": "topic-charging",
        "definition": "The plot of terminal voltage against delivered capacity at a given current and temperature. Its shape identifies the chemistry — LFP is flat, NMC slopes — and its area is the delivered energy.",
        "related": [
          "discharge",
          "voltage-plateau",
          "nominal-voltage",
          "ocv-soc-curve"
        ],
        "lesson": "fundamentals/capacity-and-c-rate/#area",
        "url": "https://lemonergy.com/learn/glossary/discharge-curve/",
        "mentions": [
          "voltage"
        ]
      }
    },
    {
      "id": "term:state-of-charge",
      "type": "Term",
      "label": "State of charge",
      "properties": {
        "id": "state-of-charge",
        "name": "State of charge",
        "abbr": "SOC",
        "section": "topic-state",
        "definition": "How full a cell is, as a fraction of its available capacity. State of charge, like temperature, affects how fast a stored cell ages.",
        "unit": "%",
        "related": [
          "depth-of-discharge",
          "ocv-soc-curve",
          "coulomb-counting",
          "state-of-health",
          "bms"
        ],
        "lesson": "fundamentals/battery-aging/#storage-soc",
        "example": {
          "title": "Interpret a charge inventory",
          "text": "If available capacity is 5 Ah and 3 Ah remains by the chosen estimator, SOC is 60%. A different estimate of available capacity changes this percentage, so compare SOC values only with the capacity convention recorded."
        },
        "url": "https://lemonergy.com/learn/glossary/state-of-charge/",
        "mentions": [
          "usable-capacity"
        ]
      }
    },
    {
      "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"
        ]
      }
    }
  ]
}