Home Forums Truck Camper Adventure Forum Battery banks. Can I mix different batteries? Reply To: Battery banks. Can I mix different batteries?

#27964
Tom MacCallum
Participant

Thanks everyone of the responses. I should have clicked on the email notification or I would have seen this sooner.
BTW Mike, love this site since we’re a couple of old rive rats that are new to TCs or RVs of any kind for that matter.
OK, I’m going to ditch the NAPA batteries per you alls suggestions. My Scottish gene getting the better of me. I’ll sell them. It’s not like they’re high end batteries.

I had already decide to go with the Lifeline Group 31 125 AH batteries in the battery compartment. We could easily(except for the cost) put another one in the wheel well which happens to be almost right under the the battery compartment, so minimal voltage drop due to short wire runs. Maybe this is over kill, but if we’re up north and have a few cloudy days in a row, this will delay having to use the generator. On our one and only trip so far with this camper down to “Valley of the Gods” in S. UT, the panels would charge the batteries to 13.5V and they’d be down to around to about 12.6.-12.7 in the morning using the furnace@55* in 32* temps, some lighting, and Sirius radio. This was with blue bird days the whole time. I’m definitely going to add a 3rd 100W panel. Unfortunately, I’ll have to install a large controller since the the Renogy 20A MPPT is only rated for 250W of panel input.
My thoughts on using the truck alternator to charge the auxiliary battery was just to charge when driving, not use it as another generator. This was after reading Cal Willis’ and Duncan Crawford’s articles in TCA. I was thinking of using this isolator or something similar if I go this route. http://hellroaring.com/bic95150B.php

Jeff, Thanks for the very thorough reply and especially the tip about marine gauge wire and how important voltage drop needs to be taken into consideration. TCs aren’t the easiest to route wires around. Luckily, our Adventure has a nice size chase between the wardrobe and the shower shell to get wires from the roof into the camper, but getting them between the cabover floor and the shower is a bear. Having installed the 10ga wire that came with the Renogy kit from the junction box on the roof to the controller and then switched it out to 8ga wire, my wife and I have become quite the contortionists at getting wires where they need to go. After reviewing some of the voltage drop charts, We may be doing it again with a heavier gauge. Getting the wire from the batteries compartment to the inverter location is relatively easy and short. The shunt is right next to the battery compartment.

So, a couple of questions since I’ve got you all here. Where is the best place or site to get the Lifeline batteries from?
The 100w Renogy panels at optimal output, produce 5.29A. If I have (3) panels on the roof is 8ga braided copper wire sufficient to conduct 16a 15′ to the controller and then 8-9′ to the batteries? The various calc table I found confused me by including load in the calcs.

Thanks
Tom