Patrat's best moveset in Pokémon GO is Tackle and Hyper Fang, with 7.80 damage per second, and it can deal 68.1 damage before Patrat faints. This is true when battling in neutral weather.
All Patrat movesets ranked
Here is a complete list of Patrat movesets in Pokémon GO, ranked by their DPS and TDO. You can change the weather and the opposing Pokémon.