{
  "node": {
    "id": "term:gbt-38661",
    "type": "Term",
    "label": "GB/T 38661",
    "properties": {
      "id": "gbt-38661",
      "name": "GB/T 38661",
      "section": "topic-standards-vehicle",
      "definition": "China’s technical specification for battery management systems in electric vehicles: requirements, test methods and inspection rules for the BMS of lithium-ion and nickel–metal hydride traction batteries, in force since October 2020. It gives Chinese vehicle makers and BMS suppliers a shared basis for specifying and testing the control electronics.",
      "related": [
        "bms",
        "gb-38031",
        "functional-safety",
        "state-of-charge",
        "cell-supervision-circuit"
      ],
      "url": "https://lemonergy.com/learn/glossary/gbt-38661/",
      "mentions": []
    }
  },
  "edges": [
    {
      "id": "edge:6248",
      "source": "term:gbt-38661",
      "target": "topic:topic-standards-vehicle",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:6249",
      "source": "term:gbt-38661",
      "target": "term:bms",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6250",
      "source": "term:gbt-38661",
      "target": "term:gb-38031",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6251",
      "source": "term:gbt-38661",
      "target": "term:functional-safety",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6252",
      "source": "term:gbt-38661",
      "target": "term:state-of-charge",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:6253",
      "source": "term:gbt-38661",
      "target": "term:cell-supervision-circuit",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-standards-vehicle",
      "type": "Topic",
      "label": "Vehicle and transport standards",
      "properties": {
        "id": "topic-standards-vehicle",
        "name": "Vehicle and transport standards",
        "lede": "The regulations and standards a vehicle battery must meet to be approved, and the rules for shipping batteries by road, sea and air.",
        "context": "Check issuing organization, edition, scope and market.",
        "example": "Shipping tests and vehicle battery approval tests address different uses; passing one does not automatically satisfy another.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "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"
        ]
      }
    },
    {
      "id": "term:gb-38031",
      "type": "Term",
      "label": "GB 38031",
      "properties": {
        "id": "gb-38031",
        "name": "GB 38031",
        "section": "topic-standards-vehicle",
        "definition": "China’s mandatory national safety standard for electric-vehicle traction batteries. Its 2025 revision, mandatory from July 2026, requires that a single-cell thermal runaway produce no fire or explosion in the pack, going beyond the five-minute warning of earlier rules.",
        "related": [
          "gtr-20",
          "thermal-propagation",
          "propagation-test",
          "gb-18384",
          "gbt-38661"
        ],
        "url": "https://lemonergy.com/learn/glossary/gb-38031/",
        "mentions": [
          "thermal-runaway"
        ]
      }
    },
    {
      "id": "term:functional-safety",
      "type": "Term",
      "label": "Functional safety",
      "properties": {
        "id": "functional-safety",
        "name": "Functional safety",
        "abbr": "ISO 26262",
        "aka": [
          "ASIL"
        ],
        "section": "topic-hvsafety",
        "definition": "The discipline, standardised for vehicles in ISO 26262, of making sure electronic failures do not cause harm. Battery functions such as overvoltage protection are classified by risk into ASIL levels A to D, which set how redundant and verified their hardware and software must be.",
        "related": [
          "bms",
          "high-voltage-interlock",
          "insulation-resistance",
          "fmea",
          "mcu",
          "iso-13849"
        ],
        "url": "https://lemonergy.com/learn/glossary/functional-safety/",
        "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:cell-supervision-circuit",
      "type": "Term",
      "label": "Cell supervision circuit",
      "properties": {
        "id": "cell-supervision-circuit",
        "name": "Cell supervision circuit",
        "abbr": "CSC",
        "aka": [
          "cell monitoring unit",
          "CMU",
          "slave BMS"
        ],
        "section": "topic-pack",
        "definition": "The board on each module that measures its cell voltages and temperatures and switches its balancing resistors, reporting to the central BMS controller. It is usually built around a dedicated monitoring chip and linked by isoSPI or CAN.",
        "related": [
          "bms",
          "cell-balancing",
          "isospi",
          "voltage-sense",
          "afe",
          "wireless-bms"
        ],
        "url": "https://lemonergy.com/learn/glossary/cell-supervision-circuit/",
        "mentions": []
      }
    }
  ]
}