This is a Trojan T125 6v (3 cell) deep cycle battery (weight 30kg)
This is about 200Ah so is 1.2kWh
A design for a 61 battery chassis
That one includes a controller (left in red) and a bank of supercapacitors between the batteries and controller.
Total pack capacity is 61 x 1.2kWh = 73.2kWh total.