Dual Battery Setups! Let's see them! Multiple Batteries Thread!

No, the diode is in use and functioning properly.

I am going to sell my Blue Sea ML-ACR.

 

After reading a few threads and people complaining about lack of space or the inner fender beginning to crack because of weight and honestly the cost involved in a dual battery mounting system I decided to just build a portable solar generator. I figured this way I can take it anywhere with me and move it from one vehicle to another or leave it at my base camp. I came up with a fairly simple system and would be glad to share the specs if anyone’s interested

 

Please do!

 

May as well share. I'd be curious to see what type of power output you can achieve and what size the unit is.

 

I've made a couple of these out of 32650 LiPo cells. A 110ah version (4s20p) in a pelican case that I keep in the truck, and a more portable 25ah (4s5p) in a 30cal ammo can. I have BMS boards in both for balancing. The big unit has a solar charge controller in it, little one does not. The cheap low amperage cells don't have the C (discharge) rating of some of the large ($$$$) prismatic ones. But with 20 cells in parallel, 60amps from the large one is still not a problem. I opted to just put terminals on the large unit, because I didnt want to drill a bunch of holes for powerpoles and USB. The BMS boards are $12 ebay specials. Incorporating BMS makes them somewhat complex, but they are required. The 110ah battery weighs 27lb.

These were really just "proof of concept" excercises since I already have a battery spot welder and enough electronic skills to be dangerous. I can't justify dropping $1000 on a factory LiPo battery.

 

Please furnish more details about the larger pack. Photos of the interior? What brand cells? Link to BMS and solar controller? Budget to build? This would suit me well for ham radio.

 

I use mine for ham radio as well. Photo is of the cells and BMS wiring (I had the batteries in a different box during testing). A 100w panel does a good job charging the pack. The BMS can't take more than 10amp charge current. If I don't have sun I charge it with a programmable hobby charger that is made for drone/rc batteries. All in, I probably have $250 in the battery pack. The BMS controls discharge and cuts out when voltage goes below cutoff to keep batteries from being damaged. I've tested this, and it works fine. The balancing circuit components seem pretty low amperage for 100a pack, but ideally the 4 banks should not get that far out of wack if you charge them equally/separately before using.

I've made several Li battery packs with my cheap chinese spot welder, so it has paid for itself. I converted my MFJ-269 to run on 18650 LiPo cells instead of the dumb 10 AA battery setup MFJ uses...

Here are some of the parts:
100A BMS:
https://www.ebay.com/p/4s-Balance-1...34&rk=3&rkt=7&&_trksid=p2349526.c100534.m4207

Solar controller is a Renogy Voyager. Important to use a LiPo compatible unit (not lead acid or Li Ion...) there arent that many. BMS manual says that you can just plug 15v into it and it will control charge, but I didn't want to chance that.
https://www.ebay.com/itm/Renogy-Voy...2V-Battery-Regulator-/282662544269?nav=SEARCH

32650 cells are similar to these. I bought 80 5.5AH cells for about $160. Seems they are more expensive now than a year ago, and not as prolific on ebay:

https://www.ebay.com/itm/10x-32650-...-High-Quality-Cell-0-/153454141467?nav=SEARCH

 

I got the idea from this website, which has youtube vids:

http://www.kerrywong.com/2017/09/22...-using-80-32650-lifepo4-cells/comment-page-1/

Commenters mention the bleed resistor deficiency for balancing on the BMS board. I think they may have a bad board. I've used several, and one was kindof squirrly. Id suggest getting a backup if you try making a pack. I've been using my battery for a year with no problems. I also never pull more than 50a from it....

 

Well I try to upload a video but it wouldn’t load. If you’d like to send me a PM with your email address I can send it that way.

I started with a Ridged brand plastic rolling tool box. Wanted something strong that had quality wheels and I could sit on. Next I made an aluminum platform that I attached to the floor of the box with screws and lock nuts and sealed the holes with RTV. I mounded my battery to this. I used Renogy Wanderer solar controller, their 100watt solar panel and a 6 circuit fuse block. All purchased from Amazon. I needed a ground block to attach all the wires to so I made one from a piece of plastic and aluminum strap that I drilled and tapped. For a battery I used a group 34 Optima blue top. I also added a 12 volt outlet and USB ports with volt gauge. Once I have more funds I will add 1000 W converter to run small appliances. The only thing I would’ve done different was purchased a folding solar panel as the one I selected is a little large

 

Truck has been sitting in the garage for more than a year, need to fix all the wiring from the engine to the batteries. also bough a battery selector and want to install it, where is everybody getting the wire and terminals? what type of wire are you using, want to get some good one because the one I have is getting rust on the inside.

 

Welding cable Amazon.

 

I’ve really liked the temco wire and tinted copper lugs. Been getting mine on eBay.
They also have colored glue lined heat shrink.

I HIGHLY suggest one of the hydronic crimpers for the larger wire.

 

what level of tint? Hydraulic might work better

 

Anyone has a selector installed? If so where did you mounted it.

 

Nice

 

https://www.wiringproducts.com/
I bought smaller gauge stuff, not sure of the quality of the larger wire.

 

I use Ancor marine wiring, and get it (and connectors, shrink wrap, etc.) from Del City.

Great products, good prices, great customer service.

 

Me and spell check don’t get along....

If I ever have no spelling or grammar errors then my account has been hacked!

 

Finally purchased the Singer stage 2 mod. Now I can keep the charge on the odyssey’s.