Do not rush the cooking by turning up the heat, as you will have crispy outsides but under done insides. Medium heat provides the best results.
For the crispiest patties, flatten the batter to very thin. They will look slightly less attractive but, in my opinion, this will create tastier patties. You could also pretreat the shredded zucchini by salting, letting it sit and then squeezing out the excess water before adding to the bowl. If you do this, decrease flour to ½ cup.
Nutrition values are estimates only, using online calculators. Please verify using your own data.