Battery Health / Degradation Estimator
Estimate current SOH from measured capacity vs original, and project capacity fade over 10 years based on chemistry, temperature, and fast-charge frequency.
How this works
SOH = current capacity / original capacity × 100%. Degradation per cycle increases with temperature (Arrhenius-inspired) and DC fast charge frequency.
Methodology
Capacity fade modeled as: SOH(n) = 100% - n × r_eff, where r_eff = r_base × T_factor × FC_factor. Temperature factor uses simplified Arrhenius scaling (factor 1.8 per 10°C above 35°C for LFP, 2.0 for NMC). Fast charge penalty adds 12% (weekly) or 25% (daily) to base degradation rate. Based on published cycle-life data from peer-reviewed studies on commercial Li-ion cells.
Calculator Inputs
LFP degrades slower, tolerates heat better, warrants to 80% SOH. Used in Tata Nexon EV, MG ZS EV.
From vehicle spec sheet (new battery)
From BMS diagnostic (vehicle health report or OBD)
Estimate: total km ÷ WLTP range. E.g. 60,000 km ÷ 300 km = 200 cycles
⚠️ Moderate — 30–40°C accelerates degradation noticeably
DC fast charging (CCS/CHAdeMO) causes additional lithium plating stress
| Current SOH (measured) | 92.6% |
| Manufacturer warranty threshold | 80% SOH |
| Remaining capacity above warranty | 12.6% |
| Estimated remaining cycles | ~3,748 cycles |
| Degradation rate (at your conditions) | 0.0034%/cycle |
Projection assumes ~300 cycles/year at current conditions. Cooler storage and slower charging will extend life significantly.