{
"node": {
"id": "term:incremental-capacity-analysis",
"type": "Term",
"label": "Incremental capacity analysis",
"properties": {
"id": "incremental-capacity-analysis",
"name": "Incremental capacity analysis",
"abbr": "ICA",
"aka": [
"dQ/dV"
],
"section": "topic-state",
"definition": "The inverse of differential voltage analysis: the derivative of charge with respect to voltage, plotted against voltage. Plateaus in the voltage curve become peaks whose height and position track aging, and it can be run on data a BMS already records.",
"formula": "dQ/dV vs V",
"related": [
"differential-voltage-analysis",
"voltage-plateau",
"state-of-health"
],
"example": {
"title": "Read capacity per voltage interval",
"text": "If 0.10 Ah is transferred while voltage rises by 0.020 V, the local incremental capacity is about 5 Ah/V. Numerical differentiation can amplify noise, so a peak must be assessed with the measurement conditions."
},
"url": "https://lemonergy.com/learn/glossary/incremental-capacity-analysis/",
"mentions": [
"discharge-curve",
"bms"
]
}
},
"edges": [
{
"id": "edge:1323",
"source": "term:incremental-capacity-analysis",
"target": "topic:topic-state",
"type": "belongsTo",
"properties": {
"sourceFile": "terms.json"
}
},
{
"id": "edge:1324",
"source": "term:incremental-capacity-analysis",
"target": "term:differential-voltage-analysis",
"type": "relatedTo",
"properties": {
"sourceFile": "terms.json",
"meaning": "Related context; not a causal claim"
}
},
{
"id": "edge:1325",
"source": "term:incremental-capacity-analysis",
"target": "term:voltage-plateau",
"type": "relatedTo",
"properties": {
"sourceFile": "terms.json",
"meaning": "Related context; not a causal claim"
}
},
{
"id": "edge:1326",
"source": "term:incremental-capacity-analysis",
"target": "term:state-of-health",
"type": "relatedTo",
"properties": {
"sourceFile": "terms.json",
"meaning": "Related context; not a causal claim"
}
},
{
"id": "edge:mentions/incremental-capacity-analysis/discharge-curve",
"source": "term:incremental-capacity-analysis",
"target": "term:discharge-curve",
"type": "mentions",
"properties": {
"sourceFile": "terms.json",
"method": "build_glossary.mention_index + mentions",
"field": "definition",
"meaning": "Text mention; not a causal claim"
}
},
{
"id": "edge:mentions/incremental-capacity-analysis/bms",
"source": "term:incremental-capacity-analysis",
"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:1329",
"source": "term:incremental-capacity-analysis",
"target": "visual:voltage-derivatives",
"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:differential-voltage-analysis",
"type": "Term",
"label": "Differential voltage analysis",
"properties": {
"id": "differential-voltage-analysis",
"name": "Differential voltage analysis",
"abbr": "DVA",
"aka": [
"dV/dQ"
],
"section": "topic-state",
"definition": "Plotting the derivative of voltage with respect to charge during a slow cycle. Its peaks mark electrode phase transitions, and how they shift between cycles separates lithium inventory loss from active-material loss without opening the cell.",
"formula": "dV/dQ vs Q",
"related": [
"incremental-capacity-analysis",
"loss-of-lithium-inventory",
"loss-of-active-material",
"phase-transition"
],
"example": {
"title": "Interpret a local slope",
"text": "If voltage changes by 0.020 V over 0.10 Ah in a slowly measured region, the local slope is approximately 0.20 V/Ah. Comparing curves requires consistent current, temperature, sampling and preprocessing."
},
"url": "https://lemonergy.com/learn/glossary/differential-voltage-analysis/",
"mentions": [
"electrode"
]
}
},
{
"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"
]
}
},
{
"id": "term:state-of-health",
"type": "Term",
"label": "State of health",
"properties": {
"id": "state-of-health",
"name": "State of health",
"abbr": "SOH",
"section": "topic-state",
"definition": "A summary of how far a cell has aged, often expressed through remaining capacity or increased resistance compared with when it was new. By convention a cell has reached end of life at 80 % of its rated capacity.",
"unit": "%",
"related": [
"capacity-fade",
"impedance-rise",
"end-of-life",
"remaining-useful-life",
"state-of-charge",
"state-of-certified-energy"
],
"lesson": "fundamentals/capacity-and-c-rate/#real-cells",
"url": "https://lemonergy.com/learn/glossary/state-of-health/",
"mentions": [
"nominal-capacity"
]
}
},
{
"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: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": "visual:voltage-derivatives",
"type": "Visual",
"label": "A voltage plateau becomes an ICA peak",
"properties": {
"title": "A voltage plateau becomes an ICA peak",
"summary": "Differentiate an authored monotonic voltage curve to see the information in DVA and ICA.",
"readout": "At the plateau center, dV/dq = 0.44 V per charge fraction; dq/dV = 2.273 charge fraction/V.",
"formula": "DVA = dV/dq; ICA = dq/dV = 1 / (dV/dq), q = Q/Q_nominal",
"note": "Normalized authored curve, not a measured cell fingerprint. Peak changes alone do not uniquely identify a degradation mechanism.",
"software": {
"status": "reference",
"label": "Reference concept",
"body": "These derivatives illustrate the analysis. battery-core does not extract aging mechanisms from measured voltage data; real differentiation needs sampling and noise treatment.",
"href": "../chapter-1/"
},
"html": "Authored voltage curve