What Is the Lithium-Ion Battery Capacity Fade & State of Health Calculator?
Battery State of Health (SoH) tracks the percentage of original usable energy storage capacity remaining in a battery cell.
How Does the Lithium-Ion Battery Capacity Fade & State of Health Calculator Work?
Combines calendar aging (SEI growth on graphite anode proportional to t^0.5) and cycling aging with Arrhenius temperature acceleration.
Lithium-Ion Battery Capacity Fade & State of Health Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
Delta Q = k_{ ext{cal}} e^{- rac{E_{a, ext{cal}}}{RT}} t^{0.5} + k_{ ext{cyc}} e^{- rac{E_{a, ext{cyc}}}{RT}} N_{ ext{cycles}}^{0.5}, quad ext{SoH} = rac{Q_{ ext{rem}}}{Q_0} imes 100%
Semi-empirical Arrhenius power-law model for lithium-ion calendar and cyclic capacity fade.
How to Use the Lithium-Ion Battery Capacity Fade & State of Health Calculator
- Input nominal capacity in Ah, equivalent full cycles, average temperature in °C, and elapsed calendar days.
Step-by-Step Example Calculation
EV Traction Battery Pack Aging
Input Values:
initialCapacityAh:60
equivalentFullCycles:1200
cellTemperatureC:32
storageTimeDays:500
Worked Steps: Calendar loss = 2.07 Ah, Cycling loss = 4.41 Ah, Remaining capacity = 53.5 Ah, SoH = 89.2%.
Understanding Your Result
Reports remaining capacity in Ah, current State of Health (SoH) percentage, and calendar vs cycling loss breakdown.
Factors That Affect the Result
- Elevated temperature accelerates parasitic side reactions; high charging rates accelerate particle microcracking.
When Should You Use This Calculator?
- Electric vehicle warranty assessment, stationary battery storage financial modeling, and second-life battery screening.
Assumptions & Limitations
- Assumes standard NMC/graphite chemistry without sudden non-linear aging knee onset.
Frequently Asked Questions
Calculation Accuracy & Reference Note
Standard semi-empirical battery degradation modeling.