A way to fit two golf cart batteries in the tub, and tidying up the rat's nest with bus bars

ChanW · December 2018

(It took way longer than I expected, and way longer than I wanted it to, but...)

Here's a way to squeeze 2 golf cart batteries, along with the propane tank, into the stock tub!

First had to pull out the existing battery frame and propane bracket (actually pretty easy on our 2014 model because it was just bolted in in the early Little Guy Tab). Then put in a full floor of ¾" plywood.

The battery boxes were left out of the equation, because they take up so much room.

To be able to have twin propane cylinders, with a full one available as backup, I went with two 10# cylinders. (the spare goes in the truck).

BTW, if you can find them, I can't say enough about Crown Battery customer care... The district manager for the Northeast shipped them directly to me because they had no rep in my area! The price was equivalent to locally procured Trojans, including shipping! Great company.

Awca12a · December 2018

Food for thought:
You have exposed battery terminals in the same place as a propane tank. The red protector cap on one of the negatives is already missing and it's not out of the realm of probability that others will fall off as well. This configuration can allow a terminal to be contacted when taking out a tank or someone tossing an item into this tub without thinking about it. If vented battery boxes absolutely can't be used, what I've done with somewhat similar battery install problems was to put a sheet of rubber or plywood over the tops of the batteries to give some, albeit limited, mechanical protection from a possible dead short. You'd be amazed how quickly two exposed battery terminals can get crossed even by experienced mechanics.
LP gs is heavier than air and will pool so if there is any kind of leak or discharge while this design is convenient and solves some problems, I'd suggest taking the battery terminal protection from mechanical short a bit further.

ChanW · December 2018

Yeah, that's first on my to do list for finishing the job.

Actually those missing caps on the negative posts haven't fallen off, they weren't supplied with the batteries.

There are a few more things to do before I will call it finished!

Thanks for the nudge!

jkjenn · December 2018

Nice, clean install, @ChanW!

ChanW · December 2018

Thanks @jkjenn.

It's really only clean because I ended up with less stowage space! Now I'll need to find a place for our black wash-down hose, and the BAL Leveler. Argh!

And hopefully, next is figuring out out a solar system, to make use of that great battery capacity.

rajamar · December 2018

Are you planning any sort of battery covers? I would be worried that the gap at the back of the lid would allow water to pool on the top of the batteries during heavy downpours. If not, maybe just pop-rivet or bolt on rubber flaps to direct water to below the battery tops?

ChanW · December 2018

Yes, @rajamar I've been looking into 'flap seals', kind of like the seal along the side edges of the tub, to run across that top opening.

Here's one that might work (I haven't measured the gap yet):

(Actually, now that I look at it, I think this would be better if reversed - I'll keep looking)

From here:
http://uni-grip.com/products/flap-seals

ChanW · May 2019

Have added a couple of bus-bars to tidy up the wiring for the two 6v batteries, and to/from the controller & shunt. Also cleaned up the solar cables' entrance into the tub with a GoPower Cable Entry Plate.

Mounted the Victron solar controller in the tub, along with the battery monitor and its shunt (the shunt is inside the black plastic utility box). I think the data readout is much easier off the phone or tablet, so won't need to use the monitor's (difficult to read & navigate) display.

I put a 'false floor' on top of the bus-bars to protect and hide them. It's made of that light weight plastic corrugated sign material that's used for garage sale signs.

I wanted the potential of charging the batteries while on the road, something we definitely learned was lacking, after having depleted our battery too far overnight a few times... It's hard to restore a battery's charge without hookups, at a national park, or boondocking, when we're on the road during the sunniest part of the day. Our TV's alternator wasn't doing the trick.

So we put two solar panels on the truck's 'ladder rack'. Our rack's verticals are adjustable front to back, which made it easy to set them at the right distance for the panels' length.

On the road, a heavy duty single cable runs from the panels, below the tailgate, and along the a-frame, to plug in while we're hitched up and towing.

We have 30 feet of extension cable for parking the truck in the sun while the Tab's in the shade. And the solar panels come off easily, four nuts each, so if we want to set them up somewhere other than where the truck is parked, we can.

So, just a few ideas to throw out there.

ChanW · May 2019

Also, Victron offers a terminal cover & 'strain relief' for their MPPT 75 & 100 controllers. Like this:

rcuomo · May 2019

Chan, nice installation. I might steal your ideas using the 10 gallon tank saddled by two batteries. I couldn’t find the specs on the Crown batteries. How many AHs?

ChanW · May 2019

Thanks @rcuomo. They're 225aH batteries.

One caveat to the install... I found that the lid of the tub needs to come off in order to remove the batteries! (I found out too late!

)

A different type of propane tank hold-down might be a way around that. Mine's pretty overbuilt, and inflexible.

rcuomo · May 2019

Chan- 225aH each? 450aH on board, that’s pretty awesome. With that kind of power and a 2000w inverter you could run the Danby 5000 BTU AC.

rcuomo · May 2019

Oops, my bad forgot they are 6v. Still if they are the CR220 batteries, 220Ah is pretty good for the footprint.

ChanW · May 2019

Yes, my mistake. 220aH. (225 just seems like a better number

I think 225 might be the size of an old Chevy engine)

ChanW · May 2019

BTW, in response to my question to Crown tech re: Crown charging parameters, it was suggested that three solar panels would be better with that size battery, esp. if regularly discharging to recommended minimum levels. (I expect we won't regularly discharge to that level though)

I'll quote it here for you (cuz I'm not so smart as they!)
from MaLinda Laurer, tech support at Crown Battery:

...
The suggested settings for your 12 volt system are also listed below:
Daily Charge (Absorption):           14.5
Equalize:                                     15.5
Float:                                          13.5
The bulk setting should be set at the same or a little higher than the absorption phase (14.5 to 15). This is the phase where 80 to 85% of the current is returned to the battery. The absorption phase will follow the bulk phase and is where the battery is "topped off" to insure that the battery receives full charge.
These settings are assumptions based on the depth of discharge being limited to between 30% and 50% of the batteries rated capacity. Also that the panel array / turbine capacity output (RE power source that is being used) is properly matched to the battery bank's capacity, which should be approximately 8 to 10 amps of current charge input for every 100 amp hours (at a 20 hour rating) of the battery's rated capacity. It is recommended that at a minimum that you equalize your batteries every 30 days. If you are discharging your batteries below 50% of their rated capacity you should equalize more frequently.
To maximize performance and life of your deep cycle batteries they should be fully recharged after each discharge period. To verify full recharge of your batteries it is important to monitor individual battery voltage and specific gravity after every charging period (battery testing instructions are located on page 6 of the attached brochure). If the battery bank is not at least 2.12 volts per cell (VPC) and have a specific gravity (SG) rating of 1.265 per cell after absorption has completed, the absorption voltage settings need to be increased or the time needs to be extended. The suggested initial time setting should be 2.5 to 3 hours for the absorption phase and 1.5 to 2 hours for the equalization phase. However if the batteries are reaching the 2.12 VPC and the 1.265 SG and are gassing excessively the absorption voltage settings need to be decreased or the time needs to be reduced.
It is important to allow the battery bank to float (rest) before the next discharge cycle begins. It is ideal to have the battery bank fully charged by late morning or early afternoon to give the battery bank rest time throughout the balance of the afternoon before the next discharge cycle.
Please remember that the information provided are suggestions and that RE systems are always changing (season changes, living arrangements, ect.). Please make the proper adjustments revisiting your charger settings periodically to ensure optimum system performance.
...

rcuomo · May 2019

Chrysler slant 6. 😉

ChanW · May 2019

Ah! The Valiant! Great car.

A way to fit two golf cart batteries in the tub, and tidying up the rat's nest with bus bars

Comments

Categories