Thank you for your answer,

So you just recommend me to put the auto-isolator without adding a second battery? Can you tell me an auto-isolator I need? I already have a separate circuit for accessories with a fuse box.

Sorry if I misunderstood your explanation, I use google translator

First a big thank you for this forum and its many topics that helped me in the modification of my Zforce800.

I would like a little help, I currently have 2 led bar, rocks led, 1 sound system, 1 led storage box, 2 rear work led.
Of course all that consumes a lot, of course I'm very careful not to put everything at the same time but even like that I would like a backup battery in case I'm far from home;)
I read the topics about batteries and I would like to know if it could work for what i want?
https://www.amazon.co.uk/Charge-140amp-Voltage-110amp-SCKC302/dp/B01FSLSE8A/ref=sxbs_sxwds-stvp?keywords=12v+isolator+charge&pd_rd_i=B01FSLSE8A&pd_rd_r=9a0699b8-d178-4c9d-ae1a-043a672b84b1&pd_rd_w=PmUaH&pd_rd_wg=cY8Ty&pf_rd_p=7dc56c0d-8a5f-4d97-9143-7233b106859a&pf_rd_r=WXFF2ZCXEKBC48ZC101M&qid=1562059305&s=gateway

Thank you for your help and sorry for the English translation, I am in Portugal;)