Flow Battery

Ratings are based on a 1 to 5 scale:
25 flow = 30% chance
50 flow = 25% chance
100 flow = 20% chance
150 flow = 15% chance
200 flow = 10% chance

The odds of getting more flow from the battery decreases by 5% as we go up.
See the below captions for reference and odds of getting 25 flow (lowest) in comparison to 200 flow (highest).