The second pole is necessary for the neutral to the switch light.
Do you need a switch light?
If not, parallel both poles. Just make both paths share similar currents. Of course you need two pieces of cable with proper connectors for the job. Get those from some old washing machine wiring loom.
Before that make sure the rocker switch is a complete double pole rocker switch and not some stripped version single pole with light.
Then each pole draws under 7A which should last more or less forever.