Pack Parameters Setup
Stacking {{ series }} cells in series for voltage.
Combining {{ parallel }} cells in parallel per series group.
*Current assumptions are illustrative only. Real allowable current depends on the exact cell datasheet, temperature, state of charge, aging, interconnects, protection and thermal design.
Theoretical Pack Characteristics Total Cells: {{ totalCellCount }}
Nominal Voltage
{{ packNominalVoltage.toFixed(1) }} V
{{ series }} × {{ currentCell.vNom }}V
Pack Capacity
{{ packCapacity.toFixed(1) }} Ah
{{ parallel }} × {{ currentCell.ah }}Ah
Nominal Energy Estimate
{{ packEnergyWh.toFixed(0) }} Wh
{{ packNominalVoltage.toFixed(1) }}V × {{ packCapacity.toFixed(1) }}Ah
Illustrative Current Sum*
{{ maxContinuousCurrent.toFixed(0) }} A
Ideal equal sharing: {{ parallel }} × {{ (currentCell.maxC * currentCell.ah).toFixed(0) }}A
Illustrative profile span only ({{ packMinVoltage.toFixed(1) }}V to {{ packMaxVoltage.toFixed(1) }}V); use the exact manufacturer documentation for real cells.
Interactive Visual Cell Matrix Diagram
Click two numbered nodes (0 through S) to compare idealized nominal potential differences.
Reverse Pack Engineering Challenge
Select the correct series and parallel matrix to fulfill application requirements.
Score
{{ challengeScore }}
Streak
{{ challengeStreak }}🔥
{{ activeChallenge.title }}
{{ activeChallenge.description }}
Available Cell Specs
{{ activeChallenge.cellNom }}V / {{ activeChallenge.cellAh }}Ah
Chemistry: {{ activeChallenge.chemistryName }}
Target Pack Specifications
Target Energy: {{ (activeChallenge.targetV * activeChallenge.targetAh).toFixed(0) }} Wh
Set the S/P Arithmetic:
Calculated V: {{ (userS * activeChallenge.cellNom).toFixed(1) }} V
Calculated Capacity: {{ (userP * activeChallenge.cellAh).toFixed(1) }} Ah
Worksheet Result: {{ userS }}S{{ userP }}P ({{ userS * userP }} Cells Total)
Voltage Match: {{ (userS * activeChallenge.cellNom).toFixed(1) }}V / {{ activeChallenge.targetV }}V | Capacity Match: {{ (userP * activeChallenge.cellAh).toFixed(1) }}Ah / {{ activeChallenge.targetAh }}Ah
{{ challengeFeedback.title }}
{{ challengeFeedback.message }}
Cell Mismatch & Protection Concepts
Explore why combining mismatched cell capacities or initial state-of-charge voltages creates severe hazards.
Discharge Simulation (4S String)
Cells 1, 2, and 4 are healthy 3.0 Ah cells.
Cell 3 is a degraded/mismatched 1.5 Ah cell.
Idealized Low-Voltage Cutoff
Example teaching threshold: 2.80 V
Cutoff Model: {{ bmsTripped ? 'THRESHOLD REACHED' : 'MODEL RUNNING' }}
This teaching model clamps Cell 3 at the example 2.80V threshold. Real protection behavior and limits are cell- and system-specific.
Model warning: Cell 3 has moved below this example profile boundary. Do not interpret the displayed voltage as a universal safe/unsafe cutoff.
4S Series Cell Voltages
Cell 1 (3.0Ah)
{{ cell1Voltage.toFixed(2) }} V
Cell 2 (3.0Ah)
{{ cell2Voltage.toFixed(2) }} V
Cell 3 (1.5Ah ⚠️)
{{ cell3Voltage.toFixed(2) }} V
Cell 4 (3.0Ah)
{{ cell4Voltage.toFixed(2) }} V
Series String Bottleneck Concept
Because the same string current passes through every series cell, the lower-capacity example cell reaches its modeled lower boundary earlier. This simplified linear voltage model does not predict electrochemical failure, reversal, temperature, or a real protection trip point.
Simplified Parallel Equalization Estimate
Initial Equalization-Current Estimate:
I_inrush = ΔV / (2 × R_int) = {{ Math.abs(parallelV1 - parallelV2).toFixed(2) }}V / {{ (internalR * 2).toFixed(3) }}Ω = {{ inrushCurrent.toFixed(1) }} A
Simplified Thévenin Equalization Model
With the entered voltage difference and equal per-cell internal resistance, the idealized initial current estimate is {{ inrushCurrent.toFixed(1) }} A. Real current is limited by dynamic cell impedance, interconnect resistance, temperature, state of charge, protection and other effects not modeled here.
Instantaneous internal I²R estimate (simplified):
{{ (inrushCurrent * inrushCurrent * (internalR * 2)).toFixed(1) }} W across the two entered internal resistances
Safety Scope: No Universal Voltage-Mismatch Threshold
Do not use a universal millivolt rule from this app. Acceptable matching, assembly and protection requirements must come from the exact cell/pack manufacturer documentation, applicable standards and qualified engineering procedures.
Electrochemical Curriculum
{{ currentLesson.title }}
Common Misconception Buster
"{{ currentLesson.misconception.myth }}"
{{ currentLesson.misconception.fact }}
Interactive Knowledge Quiz
Test your understanding of series and parallel battery configuration rules.
{{ activeQuestion.text }}
Explanation:
{{ activeQuestion.explanation }}