I had much better results with a wall transformer.
I ran it for 15 minuts, and the mixture turned my ice tea from a dark tea color to something like miller lite.

It no longer tase like tea, but does taste like pool water.

The transformer is 9 v and 500ma.

So it looks like it's the current, and not the voltage that is needed.

I guess 2 lithum batteries can put out quite a bit more current than a nine volt.