I purchased an AGM lead acid deep cycle battery, inverter and solar panels. All of the provided cables connecting these devices were made of thick copper.
I also have Goal Zero Yeti 400 lead acid battery which has a built-in inverter. I wanted to chain this to another AGM battery using its mini Anderson plug port. I went to an electrical shop and they gave me what I needed to chain the batteries and it’s all working fine. The cables that they gave me for connecting the chaining port to the terminals on the second battery were much thinner cables made of a silver coloured metal. What metal is this likely to be? The copper cables are a lot more expensive per metre and look much more robust. Are the thinner cables satisfactory or should I be using the thick copper cables for this purpose?
I can confirm that the wire is tinned copper 5x3.2mm (WxH), PVC insulated, maximum temperature 80°, rated current 7.5A, stranding 24x0.2mm, diameter 1.9mm, AWG 18. It chains the 2 batteries via a 45A Anderson powerpole connector set. The length of cable between the 2 batteries is 2m.
The purpose of my question is to prevent a catastrophe (such as a fire) and I am trying to quantify the capability of this setup. What are the quantitative limitations? Am I on the edge or well within safety limits based on the information I have provided? It’s working well so far but want to avoid any surprises later on.