Here's what I have for a battery cut off switch. Its a marine product and cost around $35; not counting the cost of custom cabling. It allows me to disconnect either one string, or the other, to disconnect all, or to have all batteries on-line. I abandoned the factory BCO, since with my inverter / charger it is no longer a viable option.
You might notice its on the negative or ground side, primarily because of convenience.
A simpler solution for simpler systems (one proposed on this post) is a simple automotive disconnect directly on the battery.
Remember before storage and before disconnecting batteries to have them fully charged. Then, remember before towing to reconnect the switch.
XLR Hyperlite 29HFS
Ram 2500 6.7L CTD
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