House battery bank

I have to replace my house battery bank. I currently have 8 six volt golf cart batteries wired in series and in parallel to give me 12 volts and 880 amp hours. Which is great.

My question is...Is there a better way to do this? Why not 12 volt batteries to give me more amp hours? Or do I stick with the golf cart batteries?

Getting the same power (or more amps hours) with less weight would be ideal as the bank is on the starboard side and the boat has a list to that side.

Arcticspud said:

I have to replace my house battery bank. I currently have 8 six volt golf cart batteries wired in series and in parallel to give me 12 volts and 880 amp hours. Which is great.

My question is...Is there a better way to do this? Why not 12 volt batteries to give me more amp hours? Or do I stick with the golf cart batteries?

Getting the same power (or more amps hours) with less weight would be ideal as the bank is on the starboard side and the boat has a list to that side.

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12 volt batteries won't give you more amp hours. Assuming the same technology, weight and capacity go pretty much hand in hand. More capacity (amp hours) equals more weight.

Golf cart batteries will always be the best bang for the buck. Stick with them. Many so called 12v deep cycle are not deep cycle batteries. Golf carts always are.

David

That seems to be the way to go. I am wondering if there is another way to go? Why not marine deep cycle 12v batteries?

Marine 12v deep cyle batteries are NOT true deep cycle batteries. They are basically some marketing nonesense to try to cover both bases, starting and deep but doing neither really well and are intended really for small boats who want to run a stereo and vhf while fishing for short periods of time.
The golf cart batteries are true deep cycle batteries and will work well for use driving house loads like fridges, pumps over much longer periods of time.
Changing to so called 12V marine deep cycles will be a backward step as far as life, ultimate cost and capacity are concerned.

If you really want to look at other batteries look up Nigel Calders, Boat Owners Mecahnical and Electrical guide and read/study it. He does a good job explaining the differences and what to look for.

There is no free lunch in flooded deep cycle batteries. To get capacity you need weight. Remember, it is all about watts. 220 ah @ 6v = 110ah @ 12. There are indeed 12 volt GC type deep cycles. People go to 6vs for ease of physical handling of the individual batteries.

I have read all of Calders books and have learned a lot. But I always like to ask the questions to see if there is a better way of doing things.

Most boats are limited by footprint to the number of batts they can ship.

6V have more lead than 12V ,( fewer spacers per cell) and its the lead weight that gives the batt its ability.

Marine compromise batts suck , as noted Boob Bait for the Bubbas.

The L -16 is usually the same footprint as golf carts , but taller , and of course more expen$ive , as their added capacity is more lead weight.

Golf carts are cheaper per KW.

Proper recharging will do the most for batt life ,and on board capacity ,while cruising but without solar it is hard to get that last 15% , to get to 100% full.

An SOC is needed to not damage the set by too much discharge.

Plan your daily loads to cycle from 50% to 85% SOC.

Most of the important points relating to golf cart batteries have been made. One other item for understanding the high frequency in which they are recommended is that the sheer volume of the golf cart battery sales make them more cost effective than other battery sizes. Don't have the figures but I would guess that of the deep cycle battery sales golf carts are 90% of the market, the others are niche items that sell lower volumes without substantial cost competition.

I have space restraints that did not allow for GC batts. Another option is Telecom batteries. They're narrower but taller. As others have said they are not marine batteries, just high capacity for the foot print. This is another option but at a higher cost to GC batteries. They are also AGMs.

Sent from my Nexus 4 using Trawler

I agree to get AH's it equates to weight in all cases but LIPO style batteries.
I'd stick with the current 6VDC Golf Cart batteries then you shouldn't have to make new battery cables and 880AH is a robust house bank for many boaters depending on your loads. I would give some serious thoughts to adding alternative charging sources meaning solar and or wind.
Bill

One more point, the GC batteries are taller, so you get more battery on the same footprint; if there's room.

I would like to increase the amp hours but like all boats, space is a premium. 880a/hr is great. I am just getting greedy and trying for more. I have looked at the solar panel thing and don't find them compelling enough to pursue yet. Just not enough bang for the buck yet. That technology will continue to get better and maybe at a later time it will be worth it.

We currently spend 2-3 days out and than transit thru a marina. The biggest limitation being kids. The wife and I could easily be out longer as the boat has 380 gallons of fuel and125 gallons of water. We have a 7.6 westerbeke gen so power on the hook is not a problem. We run it late morning and evening while preparing.

To solve the stbd list problem, have you considered splitting the 8-GC bank in two to be able to move 4 GC batts to the port side, offsetting the stbd battery bank weight? These 2 banks could be connected to maintain the single 880AH bank. Four GC batteries represent about 250 lbs. That's a significant weight shift.

Space is limited on the port side. The genset is there along with an 8D for starting. I was considering a small water ballast bag that wake boarding boats use to remedy the list.

house bank batteries

I asked what house golf cart batteries I should buy. below is the thread

http://www.trawlerforum.com/forums/s4/new-golf-cart-batteries-16582.html?

Arcticspud said:

Space is limited on the port side. The genset is there along with an 8D for starting. I was considering a small water ballast bag that wake boarding boats use to remedy the list.

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Articspud ,
If there is a god of electrical and mechanical it is Nigel Calder. The book is his bible..believe all written within its pages.
Regarding adding fat sacks..why add ballast when you can redistribute the weight you have and not work the boat harder and decrease efficiency? .
Hollywood

There is a revolution coming with batteries. No telling what is going to be on the table in 5 yrs +, until then, golf cart batteries are the best game in town.

I get the fat sack thing but it is really for when the boat is moored. Keep her from listing while we are gone and drain the bag when we leave to reduce weight.

Trojan 105 are still by far the most reliable battery I have ever used.My opinion.

http://www.amazon.com/gp/product/B0...e=as2&tag=manicycl-20&linkId=N5MYQP2V53M5MSKU

>There is a revolution coming with batteries. No telling what is going to be on the table in 5 yrs +, until then, golf cart batteries are the best game in town.<

Folks have been waiting for this revolution since the late 1800s.

Yeah, but things are different now. Mega BIG bucks in multiple countries are being poured into research because of the rush to electric cars. State of Utah has given Telsa mogul some ungodly amt of money for a battery factory for instance.

There is also the push for home solar systems. Hide and watch, we a Gonna see some new, fast charge hi cap long life batteries like never imagined. Now when WE will be able to afford them?? Altogether another question.

Just as solar panels, down 60% in what? 4 years..dollar a watt now. It is coming.

Mule said:

State of Utah has given Telsa mogul some ungodly amt of money for a battery factory for instance..

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Nevada. The money was not given as compared to the very strong desire on Musk's part to leave the state of California and it's anti business climate. Sure, lower wages, tax advantages, pro business etc fueled the growth model and necessary move. But leaving CA was essential to be able to compete on an international basis.

CaptTom said:

One more point, the GC batteries are taller, so you get more battery on the same footprint; if there's room.

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Some GCs aren't appreciably taller. Lifeline's 31s ate 9.27" tall, and their base GCs are 9.92" tall.

But then again, they also have GCs that are 13.02" and 15.73" tall, too.

Arcticspud said:

Space is limited on the port side. The genset is there along with an 8D for starting. I was considering a small water ballast bag that wake boarding boats use to remedy the list.

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You might not really need an 8D for starting? If it's dedicated for starting only, a Group 31 with decent MCAs/CCAs could perhaps replace, leaving space for at least a couple GCs (either moved from the original house bank, or added)?


-Chris