{
  "node": {
    "id": "term:usage-histogram",
    "type": "Term",
    "label": "Usage histogram",
    "properties": {
      "id": "usage-histogram",
      "name": "Usage histogram",
      "aka": [
        "load spectrum",
        "load collective",
        "residence-time histogram"
      ],
      "section": "topic-data",
      "definition": "A compact record, kept by the BMS, of how long or how much charge the battery has spent in each bin of temperature, SOC, current or C-rate. Instead of storing years of raw data it summarises the load spectrum, which feeds warranty decisions, second-life assessment and aging-model calibration.",
      "related": [
        "load-profile",
        "aging-model",
        "warranty",
        "cloud-bms",
        "battery-triage"
      ],
      "url": "https://lemonergy.com/learn/glossary/usage-histogram/",
      "mentions": [
        "c-rate",
        "state-of-charge",
        "bms"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:5216",
      "source": "term:usage-histogram",
      "target": "topic:topic-data",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5217",
      "source": "term:usage-histogram",
      "target": "term:load-profile",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5218",
      "source": "term:usage-histogram",
      "target": "term:aging-model",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5219",
      "source": "term:usage-histogram",
      "target": "term:warranty",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5220",
      "source": "term:usage-histogram",
      "target": "term:cloud-bms",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5221",
      "source": "term:usage-histogram",
      "target": "term:battery-triage",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/usage-histogram/c-rate",
      "source": "term:usage-histogram",
      "target": "term:c-rate",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/usage-histogram/state-of-charge",
      "source": "term:usage-histogram",
      "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/usage-histogram/bms",
      "source": "term:usage-histogram",
      "target": "term:bms",
      "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-data",
      "type": "Topic",
      "label": "Data, communication and electronics",
      "properties": {
        "id": "topic-data",
        "name": "Data, communication and electronics",
        "lede": "The control units, chips, protocols and file formats through which a battery is measured, controlled and logged.",
        "context": "Separate quantities from encoding and transport.",
        "example": "2500 in a log might mean 25.00 °C, 2.5 V or raw counts. Units and scale must accompany the value.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "id": "term:load-profile",
      "type": "Term",
      "label": "Load profile",
      "properties": {
        "id": "load-profile",
        "name": "Load profile",
        "aka": [
          "duty cycle",
          "drive cycle"
        ],
        "section": "topic-charging",
        "definition": "The current or power a battery must deliver as a function of time in its application — a drive cycle for a car, a daily charge–discharge pattern for storage. Aging tests built on a realistic profile predict life better than constant-current cycling.",
        "related": [
          "cycle",
          "depth-of-discharge",
          "cycle-aging",
          "regenerative-braking",
          "load"
        ],
        "url": "https://lemonergy.com/learn/glossary/load-profile/",
        "mentions": []
      }
    },
    {
      "id": "term:aging-model",
      "type": "Term",
      "label": "Aging model",
      "properties": {
        "id": "aging-model",
        "name": "Aging model",
        "aka": [
          "degradation model",
          "lifetime model"
        ],
        "section": "topic-transport",
        "definition": "A model that predicts capacity fade and resistance growth as functions of time, temperature, SOC and throughput. Empirical models fit power laws and Arrhenius terms to test data; physics-based models simulate the SEI, plating and cracking mechanisms themselves.",
        "related": [
          "square-root-of-time",
          "arrhenius",
          "calendar-aging",
          "cycle-aging",
          "remaining-useful-life",
          "digital-twin"
        ],
        "url": "https://lemonergy.com/learn/glossary/aging-model/",
        "mentions": [
          "sei",
          "state-of-charge",
          "capacity-fade",
          "impedance-rise"
        ]
      }
    },
    {
      "id": "term:warranty",
      "type": "Term",
      "label": "Battery warranty",
      "properties": {
        "id": "warranty",
        "name": "Battery warranty",
        "section": "topic-applications",
        "definition": "The manufacturer’s guarantee of capacity retention over time, for electric cars typically 70 % after 8 years or 160 000 km. It is written against state of health as the BMS reports it, which makes the SOH algorithm a contractual matter.",
        "related": [
          "state-of-health",
          "end-of-life",
          "calendar-life",
          "cycle-life",
          "throughput-limiting"
        ],
        "url": "https://lemonergy.com/learn/glossary/warranty/",
        "mentions": [
          "bms",
          "state-of-capacity"
        ]
      }
    },
    {
      "id": "term:cloud-bms",
      "type": "Term",
      "label": "Cloud BMS",
      "properties": {
        "id": "cloud-bms",
        "name": "Cloud BMS",
        "aka": [
          "off-board battery analytics",
          "battery analytics",
          "cloud battery management"
        ],
        "section": "topic-data",
        "definition": "Battery estimation and diagnostics run on servers from data sent by the vehicle or site, alongside the on-board BMS rather than replacing it. With more computing power and a whole fleet to compare against, it can fit aging models, flag cells drifting from their peers and forecast remaining life; safety functions stay on board.",
        "related": [
          "bms",
          "fleet-telematics",
          "digital-twin",
          "state-of-health",
          "remaining-useful-life",
          "usage-histogram"
        ],
        "url": "https://lemonergy.com/learn/glossary/cloud-bms/",
        "mentions": []
      }
    },
    {
      "id": "term:battery-triage",
      "type": "Term",
      "label": "Battery triage",
      "properties": {
        "id": "battery-triage",
        "name": "Battery triage",
        "aka": [
          "grading for reuse",
          "state-of-health screening"
        ],
        "section": "topic-recycling",
        "definition": "Deciding what a returned battery is good for — repair, reuse, repurposing or recycling — from its history, a visual and electrical inspection and a quick state-of-health measurement. Fast, reliable triage is what makes second life economic.",
        "related": [
          "second-life",
          "state-of-health",
          "remanufacturing",
          "battery-passport"
        ],
        "url": "https://lemonergy.com/learn/glossary/battery-triage/",
        "mentions": []
      }
    },
    {
      "id": "term:c-rate",
      "type": "Term",
      "label": "C-rate",
      "properties": {
        "id": "c-rate",
        "name": "C-rate",
        "section": "topic-ratings",
        "definition": "Current divided by nominal capacity, in reciprocal hours. 1C on a 20 Ah cell is 20 A; 2C is 40 A. C-rate lets you compare loads on cells of different sizes.",
        "formula": "C-rate = I / Q_nominal",
        "unit": "h⁻¹",
        "related": [
          "nominal-capacity",
          "ideal-duration",
          "current",
          "e-rate",
          "fast-charging"
        ],
        "lesson": "fundamentals/capacity-and-c-rate/#c-rate",
        "example": {
          "title": "Convert a rating into amperes",
          "text": "For a 5 Ah cell, 0.5C means 2.5 A, 1C means 5 A and 2C means 10 A. Dividing 2.5 A by 5 Ah returns 0.5 h⁻¹, conventionally written 0.5C."
        },
        "url": "https://lemonergy.com/learn/glossary/c-rate/",
        "mentions": []
      }
    },
    {
      "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:bms",
      "type": "Term",
      "label": "Battery management system",
      "properties": {
        "id": "bms",
        "name": "Battery management system",
        "abbr": "BMS",
        "section": "topic-pack",
        "definition": "The electronics and software that keep a battery inside its safe window: measuring every cell voltage and many temperatures, estimating SOC and SOH, balancing cells, computing current limits, controlling the contactors and reporting over the vehicle network.",
        "related": [
          "state-of-charge",
          "cell-balancing",
          "state-of-power",
          "cell-supervision-circuit",
          "contactor",
          "can-bus"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/bms/",
        "mentions": [
          "state-of-health",
          "cell-voltage"
        ]
      }
    }
  ]
}