Batteries

Topic: Batteries (Read 1818 times) previous topic - next topic

Batteries

August 11, 2016, 09:52:30 am

For quite a while now I have been thinking that I want to increase my battery capacity. Two 8D's is a bit more limiting than we have been accustomed to prior to having the Foretrav. Options in a U280 are limited unless I want to spend a whole bunch of money that I don't have.i was thinking of replacing the two 8'Ds with six, six volt wet cells.i would have done it before but what stopped me was the fact that I would have to put three batteries on each rack which makes for uneven wire lengths in the series parallel wiring configuration. I had the six volt battery configuration in our fifth wheel liked it a whole lot better than the two heavy 8d's. My question is how much am i going to lose with the weird wiring set up that I am locked into without spending a whole bunch of money.

Roland

Re: Batteries

Reply #1 – August 11, 2016, 09:59:10 am

Roland,

The answer depends on how many amps you will be using. At low amp draws, wire length is much less critical. So, running regular household 12 VDC for a long time is OK. High amp loads from an inverter, not so good.

So, if low amp draws, go with the "pair above, pair below and split pair".

If high amp draws think about each pair having one battery above, one below). All pairs would then be in the same configuration. Yes, the interconnect cables would be longer, but balanced.

Re: Batteries

Reply #2 – August 11, 2016, 11:20:21 am

Roland, would you gain amp-hour capacity with the six 6VDC batteries instead of two 8-Ds? Also, consider whether you might experience more corrosion in the battery compartment from wet cells, as compared to gel or AGM.

Re: Batteries

Reply #3 – August 11, 2016, 12:52:46 pm

I've used all wet cell batteries for 4 years and haven't had any problems. I prefer the wet cell tolerance to occasional over-charging, and the ability to test the electrolyte and verify each cell is good. Occasionally adding water is not a problem for me, as I have good access to the batteries.

Re: Batteries

Reply #4 – August 11, 2016, 12:59:24 pm

JD yes I can get more capacity with six six volt deep cycle batteries. My 8d's are wet cells, so no difference there. The watering system makes maintenance a breeze so no difference there either. It's the wiring imbalance that has me concerned.
Roland

Re: Batteries

Reply #5 – August 12, 2016, 12:20:23 pm

I've started hearing of these batteries recently. They appear to straddle the gap between lead acid and lithium ion batteries with their ability to survive being deeply discharged and not requiring a 100% recharge every time. They aren't cheap but they have no problems with dropping below 50% DOD unlike normal lead acid batteries. They come in both 12v and 4v applications.

Firefly Oasis Battery - Carbon Foam AGM

Firefly International Energy Co | Innovation takes Wings!

Firefly Battery Report - Inside Practical Sailor Blog Article

Re: Batteries

Reply #6 – August 12, 2016, 12:47:54 pm

Robert,

Interesting technology. Actually a spin off of Caterpillar Corp (just down the street in Peoria).

I have been in contact with their director of marketing several times in the last 2 years.

They are still not commercially available.

Re: Batteries

Reply #7 – August 12, 2016, 05:10:19 pm

I measured my battery box and it's not tall enough for golf cart batteries, if that's the type batteries you were considering. You'll want to make a taller cover for your battery box to contain the hydrogen gas and vent it out, away from the charger which is located right above the battery box if it's set up the way my coach is. In addition to the other stuff already mentioned above, consider the likely probability of one cell going bad in a battery. With twelve volt batteries you're okay because you can disconnect the battery with the bad cell and still have twelve volts to run everything. This happened to me and I know it's happened to other people on this forum. Also consider the cost of an 8D battery compared to the cost of a golf cart battery. Go to Parts Plus and buy their standard 8D battery for $155. You'll never find a better deal on batteries. They last just as long as other batteries. It would probably cost you four times as much to buy equivalent performance in a gel cell, agm, or golf cart battery. At this price you can trade your old batteries in every couple of years for new ones and still be far ahead. I did a bunch of research a few years ago and found out that all 8D batteries are "deep cycle" no matter what they're labeled as, so don't let them sell you a deep cycle 8D. I've been running these inexpensive Parts Plus 8D ordinary batteries for several years now and they're very high quality even though they're very low priced... If anyone knows of a better 8D battery deal please post it on here cuz I wanna buy some and do a comparison with the Parts Plus batteries.

Re: Batteries

Reply #8 – August 12, 2016, 05:17:39 pm

They are 85 bucks at Costco. Think of a bunch of drunk golfers running around a course all day and turning in the cart with usually completely depleted batteries. The shop recharges them overnight and the very next day, different drunks do the same thing with their golf cart. Golf cart batteries are rated to completely discharge and recharge over 700 times. I doubt 8d's would compare. I use golf carts batteries.

Re: Batteries

Reply #9 – August 12, 2016, 05:43:21 pm

I have been running 4 - 6V- T 145 wet cells for 4 years now, NO problems.
If something or someone screws up and they are run down and damaged I won't slit my wrists if they are ruined. I can also easily handle them if they need to come out of the compartment.
I look at batteries as a disposable item and can't get myself to invest boat loads of money on something that does the same thing but costs WAY more.

Next battery purchase may be a set of 4- L-16- 6V.

Re: Batteries

Reply #10 – August 12, 2016, 06:59:44 pm

Scott

My setup is somewhat different the yours. I don't have a battery box perse my batteries are in the open behind the rear wheel so no danger of explosive gas accumulation. The racks will support golf cart batteries. I ran six volt batteries in our fifth wheel for many years only time I had a real problem was when I ran them dry but if rather forget about that. It's the wiring configuration with three batteries on each shelf that has me concerned..... Load wise as well as getting a full charge on all batteries.

Roland

Re: Batteries

Reply #11 – August 12, 2016, 07:04:11 pm

Twig

How many batteries you be carrying on your setup?

Roland

Re: Batteries

Reply #12 – August 12, 2016, 07:09:29 pm

The l 16's and such can require regular rotation to equalize the wear like most batteries and should have identical length and size cabling.

Also require perfect water maintenace and regular equalization. Out gassing corrodes the terminals and I would reccomend a six month max cable and terminal maintenace schedule.

The hydrogen is explosive and the batteries would need warming plates if used in cold weather.

Some good reading

http://www.vonwentzel.net/Battery/01.Type/

Re: Batteries

Reply #13 – August 12, 2016, 07:56:04 pm

I believe I have the same battery tray as Roland. I put four golf cart batteries in but made a hold down for six. Using the two pairs made it easy to split the loads as they were already split for two 8d units. The cabling for the third pair will can be equalized on lengths. Had I put six of the golf cart batteries in I would have been unable to use the sewer hose holder in the rear of the left side body panel.

Re: Batteries

Reply #14 – August 12, 2016, 08:26:36 pm

Equal length cables with each pair running to a bus bar would neatly solve the cabling problem. Make each vertical pair a team in series running to positive and negative bus bars where they are paralleled, and make the length the minimum needed for the longest run. Place the bus bars to keep the high current run as short as possible... mine was a little different because I have 4 12 volt 8d's in parallel, but the same principle applies. It uses a bit more cable, but it does optimize the connections...
Don

Quote from: Roland Begin – August 12, 2016, 06:59:44 pm

It's the wiring configuration with three batteries on each shelf that has me concerned..... Load wise as well as getting a full charge on all batteries.

Roland

Re: Batteries

Reply #15 – August 13, 2016, 10:27:36 pm

Wow, I just have a single 8D for the coach and a pair of 8Ds to crank the engine. I have very low electric load so a single 8D works great for me. I think my biggest electric load is when I run my laptop computer with a 12 volt DC power cord. I don't use the inverter. I have a gas refrigerator. I'm obviously not a typical Foretraveler... Well if anyone else out there is using 8D batteries buy them at Parts Plus. I don't own stock in the company or anything.

Re: Batteries

Reply #16 – August 14, 2016, 09:45:31 am

That appears to be the opposite of most setups, I would think that one 8D would be plenty of battery for cranking. We have 2 8D's for the coach and after two nights of dry camping and running one furnace all night the batteries are needing a recharge.
But..... we all have different lifestyles and needs. So........ Whatever works for you......

Nice meeting you at the "Big Ditch", we had a great trip, hope to see you again "down the road"
Justin

Re: Batteries

Reply #17 – August 14, 2016, 09:56:43 am

We also have one 8d for start batteries and 4 six volt golf cart batteries for the house , works well

Re: Batteries

Reply #18 – August 14, 2016, 12:27:39 pm

GBS LIFEPO4 Battery 12 V100AH for electric bicycle/tool/mower etc with...

I was thinking of doing 2 of these for the house.. mine are about wore out so I need to figure out what I need and get them soon. Any ideas?
How do you think a 200ah would last compared to 4 8d's?

Re: Batteries

Reply #19 – August 14, 2016, 12:33:13 pm

Quote from: DavidS – August 14, 2016, 12:27:39 pm

GBS LIFEPO4 Battery 12 V100AH for electric bicycle/tool/mower etc with...

I was thinking of doing 2 of these for the house.. mine are about wore out so I need to figure out what I need and get them soon. Any ideas?
How do you think a 200ah would last compared to 4 8d's?

Sense of humor? replace 1000 ah with 200 ah. and $1,300 to boot.

Re: Batteries

Reply #20 – August 14, 2016, 12:36:35 pm

A little difficult to compare, as Li-ion batteries can be safely discharged far below the 50% SOC used for "regular batteries".

So, for the Li-ions say 200 amp hrs with ability to discharge to 80%= 160 amp-hrs usable

4 wet cell/AGM 8D's: 220 amp hrs times 4= 880 amp hrs with ability to discharge to 50%= 440 amp-hrs usable.

Re: Batteries

Reply #21 – August 14, 2016, 12:42:16 pm

Quote from: craneman – August 14, 2016, 12:33:13 pm

Sense of humor? replace 1000 ah with 200 ah. and $1,300 to boot.

Was thinking the maintanence would be less, I could draw them down 80% and the voltage doesnt drop until it cuts off. Plus the 2k to 5k cycles is a plus.

I think (im no expert) cost would cover itself with time? no? No boondocking as of yet (just overnight). Had a house battery fry last weekend and I think was on the verge of exploding.. that thing got hot and was exhausting fumes like crazy.. what ya think?

Re: Batteries

Reply #22 – August 14, 2016, 12:43:55 pm

Quote from: wolfe10 – August 14, 2016, 12:36:35 pm

A little difficult to compare, as Li-ion batteries can be safely discharged far below the 50% SOC used for "regular batteries".

So, for the Li-ions say 200 amp hrs with ability to discharge to 80%= 160 amp-hrs usable

4 wet cell/AGM 8D's: 220 amp hrs times 4= 880 amp hrs with ability to discharge to 50%= 440 amp-hrs usable.

The Li-on isnt much more $ to get to that 440 number with longevity. No?( again im no expert)

thanks for the discussion

Re: Batteries

Reply #23 – August 14, 2016, 12:48:55 pm

Sorry, no first hand experience with longevity of Li-ions.

Well treated AGM's, gels and higher end wet cells typically have a 6-8 year life. Poorly treated ones can be killed in a year.

Re: Batteries

Reply #24 – August 14, 2016, 12:51:37 pm

Let me also add I am terrible with batteries $:-\$ ....and tires for that matter.. they dont like me much!!

I am a busy person and we will use the motorhome 1 time a month approx (thats the plan). just want something that will last and when I get in to drive out I know the batteries will be ok. working 70hrs a week or so is hard to make time for battery care. IF you get my point.. It would be cheaper for me to look into something that will last with less maintenance

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