The SMA-assembled board as supplied is not directly suitable for carrying high currents. PCB track strengthening with solid copper wires is required in places, as detailed in magazine article # 120733 published in Elektor July & August 2013.
Resistor R1 on the SMA-assembled board supplied has a value of 2.74 kO to cater for a 36 V (typ.) battery system. To convert the circuit to other battery voltages, R1 must be removed and replaced with a different value. Recommended values are found in Table 1 in Elektor magazine article # 120733 published in Elektor July & August 2013.