{ "node": { "id": "term:voltage-plateau", "type": "Term", "label": "Voltage plateau", "properties": { "id": "voltage-plateau", "name": "Voltage plateau", "section": "topic-charging", "definition": "A stretch of the voltage curve where voltage barely changes while charge passes, because the electrode is moving between two phases at a fixed potential. LFP has one long plateau; graphite shows several small ones.", "related": [ "discharge-curve", "lfp", "phase-transition", "ocv-soc-curve" ], "url": "https://lemonergy.com/learn/glossary/voltage-plateau/", "mentions": [ "electrode", "graphite" ] } }, "edges": [ { "id": "edge:1110", "source": "term:voltage-plateau", "target": "topic:topic-charging", "type": "belongsTo", "properties": { "sourceFile": "terms.json" } }, { "id": "edge:1111", "source": "term:voltage-plateau", "target": "term:discharge-curve", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1112", "source": "term:voltage-plateau", "target": "term:lfp", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1113", "source": "term:voltage-plateau", "target": "term:phase-transition", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1114", "source": "term:voltage-plateau", "target": "term:ocv-soc-curve", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:mentions/voltage-plateau/electrode", "source": "term:voltage-plateau", "target": "term:electrode", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:mentions/voltage-plateau/graphite", "source": "term:voltage-plateau", "target": "term:graphite", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:1117", "source": "term:voltage-plateau", "target": "visual:voltage", "type": "illustratedBy", "properties": { "sourceFile": "visual-pages.json" } } ], "neighbors": [ { "id": "topic:topic-charging", "type": "Topic", "label": "Charging and discharging", "properties": { "id": "topic-charging", "name": "Charging and discharging", "lede": "How current goes in and comes out, and the limits that stop it.", "context": "Separate regulation from availability.", "example": "The same CC–CV law can operate overnight or during a short depot stop.", "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/", "lesson_label": "Open charging quantities" } }, { "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. Its shape identifies the chemistry — LFP is flat, NMC slopes — and its area is the delivered energy.", "related": [ "discharge", "voltage-plateau", "nominal-voltage", "ocv-soc-curve" ], "lesson": "fundamentals/capacity-and-c-rate/#area", "url": "https://lemonergy.com/learn/glossary/discharge-curve/", "mentions": [ "voltage" ] } }, { "id": "term:lfp", "type": "Term", "label": "LFP", "properties": { "id": "lfp", "name": "LFP", "aka": [ "lithium iron phosphate", "LiFePO₄" ], "section": "topic-chemistries", "definition": "A positive electrode material, LiFePO₄, giving cells a nominal voltage around 3.2 V, long cycle life and good thermal stability, but less energy per kilogram than nickel-rich oxides. Its flat voltage curve makes state of charge hard to read from voltage alone.", "related": [ "cathode-active-material", "nmc", "lmfp", "ocv-soc-curve", "cycle-life" ], "lesson": "fundamentals/cell-anatomy/#voltage", "example": { "title": "Chemistry is not the whole datasheet", "text": "Two LFP products can differ in format, loading, capacity and current limits. Their cathode family alone does not make them interchangeable." }, "url": "https://lemonergy.com/learn/glossary/lfp/", "mentions": [ "electrode", "positive-electrode", "nominal-voltage", "discharge-curve", "state-of-charge" ] } }, { "id": "term:phase-transition", "type": "Term", "label": "Phase transition", "properties": { "id": "phase-transition", "name": "Phase transition", "aka": [ "staging" ], "section": "topic-electrochemistry", "definition": "A change of crystal structure as lithium content varies, which fixes the potential while two phases coexist. Graphite fills in stages, LFP switches between two phases across almost its whole range, and these transitions make the peaks that aging diagnostics read.", "related": [ "voltage-plateau", "differential-voltage-analysis", "lfp", "graphite", "structural-degradation" ], "url": "https://lemonergy.com/learn/glossary/phase-transition/", "mentions": [] } }, { "id": "term:ocv-soc-curve", "type": "Term", "label": "OCV–SOC curve", "properties": { "id": "ocv-soc-curve", "name": "OCV–SOC curve", "section": "topic-state", "definition": "The characteristic relation between a cell’s open-circuit voltage and its state of charge, measured once at low current and stored in the BMS. A steep curve, as for NMC, makes SOC easy to read from voltage; LFP’s flat curve does not.", "related": [ "open-circuit-voltage", "state-of-charge", "coulomb-counting", "lfp", "voltage-plateau", "ocv-test" ], "url": "https://lemonergy.com/learn/glossary/ocv-soc-curve/", "mentions": [ "bms" ] } }, { "id": "term:electrode", "type": "Term", "label": "Electrode", "properties": { "id": "electrode", "name": "Electrode", "section": "topic-components", "definition": "A solid conductor where the cell’s reaction happens, in contact with the electrolyte. A lithium-ion cell has a negative electrode and a positive electrode, each a porous coating on a metal foil.", "related": [ "negative-electrode", "positive-electrode", "porous-electrode", "current-collector" ], "lesson": "fundamentals/cell-anatomy/#components", "example": { "title": "Two transport paths", "text": "Electrons need connected solid paths to the collector; ions need electrolyte paths to reaction sites. More of one constituent displaces others at fixed volume." }, "url": "https://lemonergy.com/learn/glossary/electrode/", "mentions": [ "electrolyte", "coating" ] } }, { "id": "term:graphite", "type": "Term", "label": "Graphite", "properties": { "id": "graphite", "name": "Graphite", "section": "topic-components", "definition": "Layered carbon, the negative active material of nearly all lithium-ion cells. Lithium intercalates between its layers up to LiC₆, a theoretical 372 mAh/g, at a potential about 0.1 V above lithium metal.", "related": [ "anode-active-material", "intercalation", "natural-graphite", "synthetic-graphite", "lithium-plating" ], "lesson": "fundamentals/cell-anatomy/#components", "example": { "title": "Compare matching mass bases", "text": "A graphite value per gram of active material cannot be directly compared with a value including binder, additive and foil." }, "url": "https://lemonergy.com/learn/glossary/graphite/", "mentions": [ "milliampere-hour", "active-material" ] } }, { "id": "visual:voltage", "type": "Visual", "label": "Voltage under load", "properties": { "title": "Voltage under load", "summary": "Discharge current creates an ohmic drop below open-circuit voltage.", "readout": "5 A through 20 mΩ gives 0.1 V ohmic drop.", "formula": "V_terminal = OCV − I_discharge R", "note": "Chosen OCV curve; no chemistry calibration, hysteresis or voltage cutoff.", "software": { "status": "studio", "label": "Voltage relationship in Studio", "body": "The native battery calculates terminal voltage from OCV and resistance. The curve here is an illustrative OCV relationship, not a fitted cell dataset.", "href": "https://design.lemonergy.com/cosim.html?example=charging-home" }, "html": "
Illustrative OCV and loaded voltage
Illustrative OCV and loaded voltageSOC (%) versus Voltage (V). Open circuit; Under load. Interpretation follows the graphs.1.802.42253.05503.67754.3100SOC (%)Voltage (V)
Open circuitUnder load (dashed)
" } } ] }