The end-of-charge voltage of a 19-cell nickel-cadmium battery, measured while still on charge,

• A. depends upon its temperature and the method used for charging
• B. must be 1.2 to 1.3 volts per cell
• C. must be 1.4 volts per cell
• D. depends upon the load

Answer: (A)

End-of-charge voltage for nickel‑cadmium cells when still on charge is not a fixed number. It varies with how hot the battery is and with how you’re charging it. Temperature affects the chemical reactions inside the cell and shifts the voltage at which the cell appears full, and different charging methods (slow trickle vs. fast/constant-current charging, or termination schemes like ΔV/dt or temperature rise) set different voltage thresholds for ending the charge. So, for a 19‑cell pack, the end-of-charge voltage you observe on charge will depend on both the temperature and the charging method used, not a single fixed value. In practice, a typical per-cell end-of-charge voltage might be around 1.45–1.5 V under common conditions, but this is not universal and will move with temperature and charging approach. This is why the best answer says it depends on temperature and charging method.