{
  "node": {
    "id": "term:auxiliary-battery",
    "type": "Term",
    "label": "Auxiliary battery",
    "properties": {
      "id": "auxiliary-battery",
      "name": "Auxiliary battery",
      "aka": [
        "12 V battery",
        "low-voltage battery"
      ],
      "section": "topic-pack",
      "definition": "The small 12 V or 48 V battery in an electric vehicle that powers the controllers, lights and locks and wakes the BMS, kept charged from the high-voltage pack through a DC/DC converter. A flat auxiliary battery immobilises the car however full the main pack is.",
      "related": [
        "dc-dc-converter",
        "lead-acid",
        "pack",
        "lin-bus"
      ],
      "url": "https://lemonergy.com/learn/glossary/auxiliary-battery/",
      "mentions": [
        "bms",
        "electric-vehicle"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:3059",
      "source": "term:auxiliary-battery",
      "target": "topic:topic-pack",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:3060",
      "source": "term:auxiliary-battery",
      "target": "term:dc-dc-converter",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3061",
      "source": "term:auxiliary-battery",
      "target": "term:lead-acid",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3062",
      "source": "term:auxiliary-battery",
      "target": "term:pack",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3063",
      "source": "term:auxiliary-battery",
      "target": "term:lin-bus",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/auxiliary-battery/bms",
      "source": "term:auxiliary-battery",
      "target": "term:bms",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/auxiliary-battery/electric-vehicle",
      "source": "term:auxiliary-battery",
      "target": "term:electric-vehicle",
      "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-pack",
      "type": "Topic",
      "label": "Modules, packs and battery management",
      "properties": {
        "id": "topic-pack",
        "name": "Modules, packs and battery management",
        "lede": "From a single cell to a working battery system, and the electronics that keep it safe.",
        "context": "Make series/parallel architecture explicit.",
        "example": "Twelve 3.6 V, 5 Ah cells in 6s2p give 21.6 V, 10 Ah and 216 Wh nominally before other restrictions.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/cell-architecture/",
        "lesson_label": "Open cell architecture"
      }
    },
    {
      "id": "term:dc-dc-converter",
      "type": "Term",
      "label": "DC/DC converter",
      "properties": {
        "id": "dc-dc-converter",
        "name": "DC/DC converter",
        "section": "topic-pack",
        "definition": "The power electronics that step the high-voltage pack down to 12 V or 48 V for the auxiliary systems, replacing the alternator of a combustion car. Boost converters also appear between an 800 V pack and a 400 V charger.",
        "related": [
          "auxiliary-battery",
          "inverter",
          "pack-voltage"
        ],
        "url": "https://lemonergy.com/learn/glossary/dc-dc-converter/",
        "mentions": [
          "charger"
        ]
      }
    },
    {
      "id": "term:lead-acid",
      "type": "Term",
      "label": "Lead–acid battery",
      "properties": {
        "id": "lead-acid",
        "name": "Lead–acid battery",
        "section": "topic-other-chemistries",
        "definition": "The oldest rechargeable chemistry, lead and lead dioxide electrodes in sulfuric acid, at 2 V per cell. Heavy and short-lived in deep cycling but cheap, recyclable and good at cold cranking, it still starts most cars and backs up most telecom sites.",
        "related": [
          "nominal-voltage",
          "recycling",
          "specific-energy"
        ],
        "lesson": "labs/battery-materials-lab/#bml-market",
        "url": "https://lemonergy.com/learn/glossary/lead-acid/",
        "mentions": []
      }
    },
    {
      "id": "term:pack",
      "type": "Term",
      "label": "Battery pack",
      "properties": {
        "id": "pack",
        "name": "Battery pack",
        "section": "topic-pack",
        "definition": "The complete battery as installed: modules or cells, the BMS, contactors and fuses, busbars, cooling, sensors and an enclosure. Its energy is the sum of its cells’ energies; its mass and volume are a good deal more.",
        "related": [
          "module",
          "bms",
          "battery-disconnect-unit",
          "thermal-management",
          "cell-to-pack-ratio",
          "enclosure"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/pack/",
        "mentions": []
      }
    },
    {
      "id": "term:lin-bus",
      "type": "Term",
      "label": "LIN bus",
      "properties": {
        "id": "lin-bus",
        "name": "LIN bus",
        "aka": [
          "Local Interconnect Network"
        ],
        "section": "topic-pack",
        "definition": "A cheap single-wire serial bus at up to 20 kbit/s with one master and several slaves, used where CAN is overkill: a smart 12 V battery sensor, a cooling fan or a heater controller reporting to the BMS.",
        "related": [
          "can-bus",
          "bms",
          "auxiliary-battery",
          "ldf"
        ],
        "url": "https://lemonergy.com/learn/glossary/lin-bus/",
        "mentions": []
      }
    },
    {
      "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:electric-vehicle",
      "type": "Term",
      "label": "Electric vehicle",
      "properties": {
        "id": "electric-vehicle",
        "name": "Electric vehicle",
        "abbr": "EV",
        "aka": [
          "BEV",
          "battery electric vehicle"
        ],
        "section": "topic-applications",
        "definition": "A vehicle driven by an electric motor from a battery charged from the grid. A battery electric vehicle has no engine; it is the largest market for lithium-ion cells and the driver of most pack technology.",
        "related": [
          "hybrid-vehicle",
          "range",
          "pack",
          "regenerative-braking",
          "maritime-battery",
          "industrial-vehicle-battery"
        ],
        "url": "https://lemonergy.com/learn/glossary/electric-vehicle/",
        "mentions": []
      }
    }
  ]
}