{ "node": { "id": "term:discharge", "type": "Term", "label": "Discharge", "properties": { "id": "discharge", "name": "Discharge", "aka": [ "discharging" ], "section": "topic-charging", "definition": "Drawing current from a cell: lithium ions leave the negative electrode, cross the electrolyte and enter the positive one, while electrons do work in the external circuit. 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It needs an external supply at a voltage above the cell’s own.", "related": [ "discharge", "cc-cv-charging", "cutoff-voltage", "charger", "charging-modes" ], "lesson": "fundamentals/cell-anatomy/#charge", "url": "https://lemonergy.com/learn/glossary/charge/", "mentions": [ "electrode", "positive-electrode", "cell-voltage" ] } }, { "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. 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More of one constituent displaces others at fixed volume." }, "url": "https://lemonergy.com/learn/glossary/electrode/", "mentions": [ "electrolyte", "coating" ] } }, { "id": "term:negative-electrode", "type": "Term", "label": "Negative electrode", "properties": { "id": "negative-electrode", "name": "Negative electrode", "section": "topic-components", "definition": "The electrode at the lower potential, usually graphite on copper foil in a lithium-ion cell. It holds the lithium when the cell is charged and releases it on discharge, and industry calls it the anode.", "related": [ "anode", "graphite", "positive-electrode", "copper-foil" ], "lesson": "fundamentals/cell-anatomy/#anode-cathode", "example": { "title": "Keep the polarity name", "text": "Graphite remains the negative electrode during charge and discharge, while the anode/cathode reaction labels change with operating direction." }, "url": "https://lemonergy.com/learn/glossary/negative-electrode/", "mentions": [ "electrode" ] } }, { "id": "term:electrolyte", "type": "Term", "label": "Electrolyte", "properties": { "id": "electrolyte", "name": "Electrolyte", "section": "topic-electrolytes", "definition": "The ion-conducting medium between the electrodes. In a liquid-electrolyte cell it fills the pores of both electrodes and the separator, so it is not a separate structural layer.", "related": [ "lithium-salt", "carbonate-solvent", "electrolyte-additive", "ionic-conductivity", "solid-electrolyte", "ionic-liquid-electrolyte" ], "lesson": "fundamentals/cell-architecture/#electrolyte", "example": { "title": "Ions and electrons", "text": "Electrolyte carries ions between electrodes; the external circuit carries electrons. The two paths serve different roles." }, "url": "https://lemonergy.com/learn/glossary/electrolyte/", "mentions": [ "separator" ] } }, { "id": "lesson:fundamentals/cell-anatomy/", "type": "Lesson", "label": "Lesson 1 · Cell anatomy", "properties": { "url": "https://lemonergy.com/learn/fundamentals/cell-anatomy/" } }, { "id": "visual:soc", "type": "Visual", "label": "Charge balance and state of charge", "properties": { "title": "Charge balance and state of charge", "summary": "SOC rises with accumulated charge; depth of discharge falls by the same amount.", "readout": "From 20% SOC, ideal full charge takes 48 min. Integration stops at 100%.", "formula": "SOC = SOC₀ + ∫ I_charge dt / Q; DOD = 1 − SOC", "note": "Current is positive into the cell. Constant capacity and 100% charge efficiency; no CC-CV taper.", "software": { "status": "studio", "label": "Charge balance in Studio", "body": "Battery state advances by integrating current over each time step. This illustration assumes fixed capacity and 100% charge efficiency; it does not implement an estimator or correct sensor drift.", "href": "https://design.lemonergy.com/cosim.html?example=charging-home" }, "html": "
Complementary charge fractions
Complementary charge fractionsTime (h) versus Capacity fraction (%). SOC; DOD. Interpretation follows the graphs.002515027531004Time (h)Capacity fraction (%)
SOCDOD (dashed)
" } } ] }