The car battery shape and size is pretty standard these days, I know you can purchase smaller lead cell batteries but why not much larger ones?

For example I have an electric van with 24 separate batteries but it would seem to make sense to make a bigger battery(especially as the voltage is 48v i.e. 4 in series) is there any limitations on how big you could build a lead battery and if so why?

I understand that batteries have cells at 2.2v each so could you just create bigger cells(driving more amps) or would you need to have many separate cells?

I understand that obviously their are weight/manif issues, but if we could forget these for now.