Dual battery set ups

[donnie d]

I’ve got a Kingfisher 2025 and I’m looking for some suggestions on dual battery setups within tight spaces. Specifically I’m planning to add a deep cycle house battery.

I’ve been thinking about putting a bus bar and the ACR in the battery/bilge compartment with the battery switch off in the port side cabinet. Bus bar being in the battery compartment would be ideal as all my current accessory wiring goes there now, direct to the battery. That space will be tight though as I have my fuel filter and wash down pump all housed there, hence putting the switch in a separate compartment so it would be accessible.

I am planning to use the blue sea mini add a battery. I assume that’s appropriate given my F150 Yamaha has a 50 amp alternator.

Anyone have suggestions or pictures to share?

Thanks for any advice!

 

[zurk]

ive put 2 lifepo4s in the starboard side compartment. upgraded the starting battery to a 103Ah northstar AGM and put in a victron BMV 712. bus bar is in the starboard side. works well.

 

[macro]

ive put 2 lifepo4s in the starboard side compartment. upgraded the starting battery to a 103Ah northstar AGM and put in a victron BMV 712. bus bar is in the starboard side. works well.

Lead is dead. I just replaced both my starting and depe cycle batteries with lifepo4. more power, 1/3 the weight. Higher float voltage.

The only place lead still has a place is in a downrigger ball

 

[bigdogg1]

Okay, thanks for muddying the waters . Much like dd, I have been drawing circuit after circuit, looking at 65A v 120A Blue Sea Kits, creating wiring sheets etc...now you add in Lithium Iron Phosphate batteries!

@macro, where did you pick up the batteries, cost per battery, and aside from the reasons above, why? I just spent time going down the rabbit hole to even see what a LiFePO4 battery is, then I like them, then I saw the price! So many questions - cost? Can you still run a Blue Sea ACR? Is the wire gauge the same b/c they run more efficiently?

Any insight or website would be greatly appreciated!

 

[macro]

I've got a smaller boat so every pound counts. Especially when its 3 inches from the transom. I went from a group 31 and a group 27 that combined weighed more than 70 Lbs in two battery boxes, to 8 batteries similar to these.. https://www.aliexpress.com/item/4000019985866.html .... In my case all my batteries are lifepo4. I'd be nervous about mixing lead and lifepo4 in parallel because of the voltage differences between the two.. The Lifepo4 will allways be a higher float voltage than the lead, so any time you paralled them, the lifepo4 would try to charge the lead... not optimal. If you run the lifepo4 off of a charge relay and just use it for accessories it will be fine. I think you could hypothetically run thinner leads between a lifepo4 battery and the starter as the lifepo4 batteries wont voltage sage on start as much, but not sure there would be any point.

 

[zurk]

make sure you do low temp lifepo4's (-20C rated) and be careful of the blue seas kit. the black one works but not the yellow one. i use relion low temp lifepo4s but i heard battleborns are better. the relions have on board heater coils and are available from polar in burnaby.

 

[e-zee]

Lead is dead. I just replaced both my starting and depe cycle batteries with lifepo4. more power, 1/3 the weight. Higher float voltage.

The only place lead still has a place is in a downrigger ball

I don’t want to hijack this thread but enlighten me on lifepo4 batteries. I did some quick google research and am intrigued. What brand are you running? Where to purchase? Approximate cost?

 

[macro]

I don’t want to hijack this thread but enlighten me on lifepo4 batteries. I did some quick google research and am intrigued. What brand are you running? Where to purchase? Approximate cost?

I bought batteries at just under 1$ us an amp hour shipped off of aliexpress. I dont want to link the exact ones, because I cant recommend them.... not until ive had a bunch of time to properly evaluate them. I dont want to inadvertantly steer anyone wrong.