"How many batteries do you need?"
Translation:Kiom da baterioj vi bezonas?
Because you have a preposition right in front of it, rule of thumb, never use accusative after "da".
Can somebody explain to me why isn't there "Cxu" in this sentence? Is it because of the "Kiom"?
I love that it accepts "pilojn" even though it isn't taught here. I feel "baterio" is too English. "Pilo" is at least from the original word, "pile". It was literally a pile of zinc, copper and electrolyte.