Simple Anode vs Step Charge

In this example we compare fast-charging degradation behaviour for the Molicel P45B cell.

Note

This is a showcase example for demonstration only. We are happy to discuss how we develop and supply degradation models for your specific cell and use case. Contact us at hello@breathebatteries.com.

Objective

Compare two fast-charging approaches under ageing:

• Step profile charging
• Simple anode control (anode potential constrained)

This example compares these KPIs across ageing:

• Charge time
• Time to 80% SoC
• State of health (SoH)
• Maximum temperature
• Maximum power
• Energy added
• Minimum anode potential

Workflow

1. Configure base test settings

clear all;
bdclose all;
clc;

cRate = 4.5;
currDischarge = cRate;

socMax = 1.0;
socMin = 0.0;

numCyclesBtwnRPTs = 50;
numRPTs = 15;
totalCycles = (numRPTs - 1) * numCyclesBtwnRPTs;

2. Load model parameters

userProfile = getenv('USERPROFILE');
filePath = fullfile(userProfile, ...
    'Breathe Battery Technologies', ...
    'Breathe Model Projects - Documents', ...
    'Proj_BM_Mono', ...
    '07_Breathe_Model_Data', ...
    '03_PBMDegv1', ...
    '02_Parameters', ...
    'MoliP45_PBMDegv1_GD_Format');
load(filePath);

3. Run the step-charge benchmark

maxCrateStepCharge = 4.0;
currChargeStepExp = maxCrateStepCharge * cRate;

resultsStepChargeSim = Run_StepCharge_Experiment( ...
    maxChargeCurrent=currChargeStepExp, ...
    dischargeCurrent=currDischarge, ...
    socMax=socMax, socMin=socMin, ...
    numRPTs=numRPTs, numCyclesBtwnRPTs=numCyclesBtwnRPTs);

4. Run simple-anode cases

currMinSimpleAnode = 1;

resultsSimpleAnodeSim_Case1 = Run_SimpleAnode_Experiment( ...
    currMaxSimpleAnode=3.75*cRate, ...
    currMinSimpleAnode=currMinSimpleAnode, ...
    voltAnodeSetpointSimpleAnode=0.04, ...
    dischargeCurrent=currDischarge, ...
    socMax=socMax, socMin=socMin, ...
    numRPTs=numRPTs, numCyclesBtwnRPTs=numCyclesBtwnRPTs);

resultsSimpleAnodeSim_Case2 = Run_SimpleAnode_Experiment( ...
    currMaxSimpleAnode=3.75*4.5, ...
    currMinSimpleAnode=currMinSimpleAnode, ...
    voltAnodeSetpointSimpleAnode=0.05, ...
    dischargeCurrent=currDischarge, ...
    socMax=socMax, socMin=socMin, ...
    numRPTs=numRPTs, numCyclesBtwnRPTs=numCyclesBtwnRPTs);

resultsSimpleAnodeSim_Case3 = Run_SimpleAnode_Experiment( ...
    currMaxSimpleAnode=4.2*4.5, ...
    currMinSimpleAnode=currMinSimpleAnode, ...
    voltAnodeSetpointSimpleAnode=0.05, ...
    dischargeCurrent=currDischarge, ...
    socMax=socMax, socMin=socMin, ...
    numRPTs=numRPTs, numCyclesBtwnRPTs=numCyclesBtwnRPTs);

5. Generate comparison outputs

resultsCell = { ...
    resultsStepChargeSim, ...
    resultsSimpleAnodeSim_Case1, ...
    resultsSimpleAnodeSim_Case2, ...
    resultsSimpleAnodeSim_Case3};

namesArray = { ...
    'Step Charge 3.75C', ...
    'voltAnode 3.75C-40mV', ...
    'voltAnode 3.75C-50mV', ...
    'voltAnode 4.2C-50mV'};

figs = Plot_Results_Comparison(resultsCell, namesArray);

Charge-segment snapshots

Step charge

Early interval (RPT 1)	Late interval (RPT 15)

Simple anode case 1 (3.75C, 40 mV)

Early interval (RPT 1)	Late interval (RPT 15)

Simple anode case 2 (3.75C, 50 mV)

Early interval (RPT 1)	Late interval (RPT 15)

Simple anode case 3 (4.2C, 50 mV)

Early interval (RPT 1)	Late interval (RPT 15)

KPI comparison plots

Charge time

Time to 80% SoC

State of health

Maximum temperature

Maximum power

Energy added

Minimum anode potential

Version 73723266