Can I Take A Power Bank On A Plane Uk. 20000mAh 20Ah 20Ah 37 V considering it has a cells all connected in parallel 20000mAh 74Whr The legal limit of battery pack in flights is 100Whr. Is this ok to bring on a plane.

It takes anything that involves the majority of power bank in carry on to be brought on flights. You can now enjoy the benefits of a high capacity. Second power banks over a certain size cannot be brought onto flights at all.
So avoid heavy-duty batteries inside the plane.
Just take Milliamp Hours1000 x Voltage Watt Hours. Deltas limit on how many power banks you can take is 3. Those were just a few examples but you get the idea. You can now enjoy the benefits of a high capacity.

