Here are all the combinations that are under consideration from the R&D center in Nanjing Science and Technology Park, China.
| Capacity | Rate | Full charge |
|---|---|---|
| 5,000 mAh | 120W | 18 minutes |
| 5,500 mAh | 100W | 34 minutes |
| 6,000 mAh | 120W | 30 minutes |
| 6,500 mAh | 100W | 49 minutes |
| 7,000 mAh | 120W | 40 minutes |
| 7,500 mAh | 100W | 63 minutes |
Not at all. It's heat which is bad for battery instead of charging speed. Modern day charging standards like Supervooc push the heat to the charger and also charge two batteries simultaneously which reduces heat generation.
You can read more about Supervooc here: https://www.androidauthority.com/supervooc-fast-charging-686000/