600 watts is an extraordinary amount of power for these tiny cables/connectors, thats something id think would be something like an Anderson Powerpole , or XT 90, or some kind of high power connector if i was building a little robot or something.
The wire insulation is rated much lower than the connector (105C vs 170C). You will certainly melt the wires before the connector.
At a higher voltage, these wires would be fine for purpose.