{ "node": { "id": "term:state-of-energy", "type": "Term", "label": "State of energy", "properties": { "id": "state-of-energy", "name": "State of energy", "abbr": "SOE", "section": "topic-state", "definition": "Remaining energy as a fraction of total energy, which differs from state of charge because the voltage falls as a cell empties. It is the quantity behind a range estimate, and is harder to estimate than SOC.", "unit": "%", "related": [ "state-of-charge", "nominal-energy", "range" ], "url": "https://lemonergy.com/learn/glossary/state-of-energy/", "mentions": [] } }, "edges": [ { "id": "edge:1254", "source": "term:state-of-energy", "target": "topic:topic-state", "type": "belongsTo", "properties": { "sourceFile": "terms.json" } }, { "id": "edge:1255", "source": "term:state-of-energy", "target": "term:state-of-charge", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1256", "source": "term:state-of-energy", "target": "term:nominal-energy", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1257", "source": "term:state-of-energy", "target": "term:range", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1258", "source": "term:state-of-energy", "target": "visual:energy-state", "type": "illustratedBy", "properties": { "sourceFile": "visual-pages.json" } } ], "neighbors": [ { "id": "topic:topic-state", "type": "Topic", "label": "State estimation", "properties": { "id": "topic-state", "name": "State estimation", "lede": "The quantities a battery management system estimates but cannot measure directly.", "context": "Distinguish internal states from noisy measurement estimates.", "example": "Current-sensor bias accumulates in coulomb counting. Exact model SOC does not establish real estimator accuracy.", "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/", "lesson_label": "Open charge balance" } }, { "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:nominal-energy", "type": "Term", "label": "Nominal energy", "properties": { "id": "nominal-energy", "name": "Nominal energy", "section": "topic-ratings", "definition": "Nominal capacity times nominal voltage, in watt-hours: the headline energy figure on a datasheet. The energy actually delivered depends on the load, the temperature and how the voltage curve is weighted.", "formula": "E = Q × V_nominal", "unit": "Wh", "related": [ "nominal-capacity", "nominal-voltage", "watt-hour", "energy-density" ], "lesson": "fundamentals/capacity-and-c-rate/#energy", "example": { "title": "Turn capacity into a nominal energy", "text": "A 5 Ah cell with a nominal voltage of 3.6 V has 18 Wh of nominal energy. This estimate uses the nominal voltage; delivered energy is the integral of measured terminal voltage multiplied by current." }, "url": "https://lemonergy.com/learn/glossary/nominal-energy/", "mentions": [ "datasheet", "discharge-curve" ] } }, { "id": "term:range", "type": "Term", "label": "Range", "properties": { "id": "range", "name": "Range", "section": "topic-applications", "definition": "How far an electric vehicle travels on a full charge: usable energy divided by consumption per kilometre. Cold weather, speed and heating cut it, and the gap between official and real range is usually consumption, not battery capacity.", "unit": "km", "related": [ "usable-capacity", "state-of-energy", "electric-vehicle", "energy-density", "energy-consumption-per-distance", "road-load-power" ], "url": "https://lemonergy.com/learn/glossary/range/", "mentions": [] } }, { "id": "visual:energy-state", "type": "Visual", "label": "Stored energy versus retained energy capacity", "properties": { "title": "Stored energy versus retained energy capacity", "summary": "State of energy describes the energy currently available; certified-energy retention compares maximum usable energy with its original certified value.", "readout": "Certified energy is 100 Wh; current maximum is 80 Wh, so SOCE is 80%. When half that current maximum is stored, SOE is 50% regardless of the SOCE value.", "formula": "SOE = E_available / E_max,now; SOCE = E_max,now / E_certified", "note": "Both ratios need stated reference conditions. Usable energy depends on temperature, load, voltage limits and the measurement method.", "software": { "status": "reference", "label": "Reference concept", "body": "This example uses 100 Wh certified energy and varies the current usable-energy capacity. It does not claim a regulatory assessment or an onboard energy estimator.", "href": "../fundamentals/capacity-and-c-rate/#energy" }, "html": "
Two different energy ratios
Two different energy ratiosCurrently available energy (Wh) versus Energy ratio (%). SOE: available / current maximum; SOCE: maximum / certified. Interpretation follows the graphs.00252550507575100100Currently available energy (Wh)Energy ratio (%)
SOE: available / current maximumSOCE: maximum / certified (dashed)
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