i'm a rank 10 player, and everytime i attack a ship i lose completely, even if the other ship has no weapons

i'm a human raider, any thoughts?

They might have more crew; if you have any, you can use Spy Probes to find their actual attack and defense, instead of just what the Battle screen says (it doesn't take crew into account). You might also have a lot more decks--the more decks you have the more damage you can take, so if your defense doesn't keep up with your decks then you'll get hit harder for it.

PVP is easy at low ranks but you have to set your ship up right.. i would suggest ranking quickly to lvl 30-40, putting all rank points into deck and then equip hull and weapons. there is minimal need for defense or shields at low ranks...
a single difference in level can make a huge difference to how strong you are, until you get into later level conflicts always target players below you, 1-5 ranks .

to compensate for the fast ranking you could find yourself a good legion with high research production.

if you want more help post up some screen shots of your ship, and good luck out there