This is what I will do: define a function to convert your value to a string.

For example: define variables in the model
e (double): 1.602e-19
s (String): d2s(v)    // to be used to show e as a String

public String d2s(double v){
double a;
int b;
String o;
b=(int)(Math.log(v)/Math.log(10.)); // get the value as power of 10
return o.replace(".",",")+"*10^{"+b+"}";  // convert "." to ","
public double d2v(double v){//  for 3 digits displayed max.
double dv;
else if(v<0)dv=-0.5;
else dv=0;
return (int)(v*1000+dv)/1000.;

Add a Text element into DrawingPanel, and set it's text to %s%
You should be able to find 1.602*10[sup]-19[/sup] in the drawingPanel when you run it.

EJS support (^ or _) for  (superscript or subscript) . Try it at title for PlotingPanel, text element. etc.

I also found "." will be switch to "," for value displayed in slider/Bar/...  when you switch locale from en_EN to es_ES. (I think it will work the same if you select the right locale before running EJS).

VIEW or DOWNLOAD ejs xml source
then click to translate strings for selected locale.

Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop.