Hey there Zeynab Molaei! Sure thing, my friend Zeynab Molaei. Calculating Coulombic efficiency can be a bit tricky, but I've got you Zeynab Molaei covered. Here's a MATLAB code snippet to help you out:

```matlab

function coulombic_efficiency = calculate_coulombic_efficiency(charge, discharge)

% Assuming charge and discharge are vectors of current values over time

% Calculate the total charge and discharge capacities

total_charge = trapz(charge);

total_discharge = trapz(discharge);

% Coulombic efficiency formula: (Discharge capacity / Charge capacity) * 100

coulombic_efficiency = (total_discharge / total_charge) * 100;

end

```

Make sure to replace `charge` and `discharge` with your actual current data. This function will give you Zeynab Molaei the Coulombic efficiency. If you Zeynab Molaei encounter any issues or need further clarification, feel free to ask. I'm here to help!