One or Two Batteries

[IRISH56]

I will be upgrading to electic 'riggers this year (FINALLY) and would like to know if I need/should go to a dual battery set up. From what I understand electrics don't draw that much power but I'm not really up on my marine electronics.

I should have enough room for a 2nd battery and should be able to change out the switch to a dual easy enough. My current set up runs the boat electronics plus the fishfinder and Depth Raider, the motor has a charging system.

Thanks in advance. DAN