Science & Environment
Battery State of Charge from Open-Circuit Voltage
Estimate battery state of charge (SOC) from a measured open-circuit voltage using a linear model.
Your inputs
Change any value to update the result instantly.
Estimated state of charge
70.8 %
Measured voltage
3.85 V
Voltage window
1.2 V
Remaining capacity fraction
0.708
Formula and working
SOC% = (Vocv − Vmin) ÷ (Vmax − Vmin) × 100
- 1
Collect the inputs
Measured open-circuit voltage = 3.85 V; Voltage at 0% SOC = 3 V; Voltage at 100% SOC = 4.2 V
- 2
Apply the formula
SOC% = (Vocv − Vmin) ÷ (Vmax − Vmin) × 100
- 3
Result
Estimated state of charge = 70.8 %
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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