Just one note, 52V or 36V doesn't matter, in the end, what matters is the wattage, if for your build as:
Motor rated 52V 750W and battery with a battery 52V 14,4A +-750Wh, number of cells = 14S x 5P = 70, more weight
Motor rated 36V 750W and battery with a battery 36V 20,8A +-750Wh, number of...