Arob wrote:

50kW chargers are generally rated based on 400V, * max amps, so 400*125A = 50kW.
Bolt pack will be under 350V when at low SOC, so 350*125 =43kW. 
Generally, that is about the best you can hope for on a 50kW unit.
By the time you reach 50% charging curve drop, the pick voltage will be about 357V (nominal voltage).
So you would never expect to see better than 43 kW on a 50kW charger.
If temps are high, cooling the pack will consume some energy and the BMS will limit charging till the temps are optimal.
Bolt can charge at about 54kW "under optimal conditions", meaning battery temps in the 60-80F range.
Chargers capable of 150A or better (Bolt will take up to 150A). 
So, 400*150 =60 kW. Yet, the best I have seen on 62kW Chargepoints is around 50kW, 
maybe limited by cables or something else, so you should look for the 62kW or 
better chargers if you are interested in maximizing speeds.
Also, the battery and cabin share cooling loops, but they are independent for heating. 
So if you are using AC, your battery temps will tend to remain lower than if you were sweating it out. 
But in winter, heating the cabin won't help.