???

You know how the chinese calculate capacity?

They just count the cells and multiply with the capacity of one cell. And I do not want to talk the 20.000mAh powerbanks that do fit in your pockets.
See the many 10.000mAh 1860 cells you can buy on Ebay and Aliexpress. No manufacturer can make them but the Chinese have them.....

A while ago I placed new 18500 cells in my chinese Canon battery. It was a so called high capacity battery of 2650mAh, the 2 cells inside were 1400mAh and serial connected! So it was actually a 1400mAh battery.

I've had good luck with the larger batteries (100Ah) hitting and surpassing their capacity ratings at .3c discharge rates.

can you share the logic or schematics on how it works? Will like to give it a try at building one.

thanks

This can be accomplished with a decent-sized 4s-6s battery and variable voltage output power supply. The power supply doesn't even need to be that powerful. Set the power supply voltage to the storage voltage of the battery you are using. This leaves capacity in the battery to absorb a discharge. When charging, if you exceed the limit of the power supply the battery will provide the buffer current. Once the charge cycle is done, the power supply can fill the battery back up to storage voltage to be ready for the next cycle. This is exactly what I do at our track, but on a smaller scale. We utilize a single 100aH LifePO4 with multiple feeds that supplies as many as six chargers. We can run any combination of charge, regenerative discharge and charging of this single battery all at once. For us, using the big LiFePO4 battery, which has a battery management system built-in, there is never a need to balance the cells. If you are going to use a large LiPo, I would periodically balance the cells.

Back when Junsi first made the 4010, we used a couple of huge diodes and a discharge bank between the power supply and the charger. That works as well without having the need for the LIPO in the "RCDischarger" design. Mind you this was to cycle batteries for airplanes. Nowadays I am unsure why people find discharging a 2s battery so compelling.