I wanted to post this as a thought experiment. I wanted to preface this by saying I do not plan to build/experiment with anything being discussed as high currents/ high voltages are being dealt with and I am no expert. I am curious on designs for a system that will take the energy from a renewable system and transport it to a car battery. Let’s say you have a system (regenerative breaking, solar, etc), whatever the case may be, and that does not act as a steady power supply. Obviously, it would not be recommended to charge the battery directly as there will large fluctuations in the battery as well as with the current. With that being said, a supercap bank would be a good “middle man” in the system to regulate the input to the battery. I am interested in complete systems that can do just that on large scales. For the battery, let’s just assume an 85kWh battery, with a voltage of 403V. The input power from the the system that will charge the battery outputs voltages anywhere from 20-100 and the current output varies from 5-60 amps. Here is an example of the configuration of the battery pack: Pack - 16 modules wired in series. 403V fully charged. Module- One of the 16 sets of cells fully charged output of 25.2V from sixsub- groups wired in series. Sub-group - One of the six sets of cells within a module. These are all connected in parallel to form a high capacity 4.2V battery (fully charged). These consist of about 74 individual cells. There are 96 total sub-groups. I would appreciate ideas and thoughts on how to deal with a system that varies drastically with the output and regulate it to charge such a large battery?