glennm
Member
Had a flat battery this morning, no biggie 2nd battery is there and jumper leads to hand. Not happy with the shorter than expected life from the optima yellow top though. Got me thinking as to whether a hard wired switch would be a better option in these cases. I have a single starter and the 2nd battery (in the engine bay) is charged via a ctek 250s. Question is are there any negatives with having say a cable (heavy) running positive to positive between the 2 batteries with an isolation switch similar to what you might see in a boat with dual batteries. I recall on the boat they suggest not switching between batteries while the ignition is on but I never had this mentioned in previous boats we have owned so I am not sure if there is a real issue of potential damage to anything. As always any ideas/recommendations are very much appreciated.