Thanks! Yes, I'm currently thinking in a set of 3u 18650 batteries to reach 11.1 volts.
Re cables, we will be using this in the forest of a remote island in the Galapagos archipelago. Once there, we need to lift the device with a telescopic pole between the canopy and dealing with cables to run the pump is not always easy. I have a older, wired, version of this device that works but wanted to improve this issue.
Sorry I didn't explain this before!
Thanks again!