Deep cycle battries and standard car battries

circlehook

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Do battries have any effect on ignition systems if there marine or non marine types
 

JASinIL2006

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There are marine and non-marine starting batteries; either will work on a boat, but I believe the marine versions are built a bit more ruggedly to handle the pounding of waves, etc.

I've heard mixed things about the use of deep cycle batteries as starting batteries, but generally it seems to be a bad idea that may shorten the life of your battery and/or leave you stranded when your motor won't start.

There also are dual-purpose batteries, but you're probably better off having a marine starting battery to get your engine running and a deep cycle battery for other electrical needs.

Even on my small boat, I like having a starting battery and a house battery, so I have backup in case one fails.
 

jimmbo

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The Marine Batteries are a bit more Rugged than the standard Auto/Truck versions.
Starting Batteries and Deep Cycle Batteries are engineered for different purposes and operation. While a Deep Cycle can often put out enough Amperage to crank an Engine for a short period, it can't do it for an extended period. A Cranking Battery will not withstand being drained for extended periods of time between chargings.
AGM Batteries(Optima is an example), and Sealed Wet Cell Batteries must Never be used in any Application where the Charging System is Unregulated, as in a lot of Outboard in the late 60s, thru till the present day
 

Scott Danforth

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Do battries have any effect on ignition systems if there marine or non marine types
on ignition systems..... NO.

all 12 volt batteries are about 12.7 volts fully charged and 12.0 volts discharged (below 12 volts just kills them)

as others mentioned.

Never use a cranking battery for a deep cycle application and never use a deep cycle battery for a cranking application.
 

JimS123

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If I wanted to have 2 batteries I would have a deep cycle and a cranking. Since I want to have only one I use a dual purpose. I usually get 8 years or so out of a marine battery. Maybe I just treat them well.

For a boat that had a lot of electronics and downriggers, etc. I replaced the Gp 24 with a Gp 31. No problems.

For a while I switched to AGM batteries and had bad luck. They didn't last as long as a wet cell. (and yes I charged them correctly). Now, the only AGM I use is in a jetski, for obvious reasons.
 

Buster53

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All I have ever used are deep cell for both house and starting. 2 sailboats with small diesels and 3 motor yachts all with big block gas engines. Never had a problem with starting with deep cells.
Everything I’ve read about the dual purpose…they‘re not great as either starting or deep purpose.
 
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airshot

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All I have ever used are deep cell for both house and starting. 2 sailboats with small diesels and 3 motor yachts all with big block gas engines. Never had a problem with starting with deep cells.
Everything I’ve read about the dual purpose…they‘re not great as either starting or deep purpose.
It is not that they wont wirk, they will as you have proved...however the battery life is greatly reduced when not used as they are designed.
 

dingbat

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Not a fan of starting batteries in marine applications. Deep cycle are just so much more robust than starting batteries

Run twin grp. 27 deep cycle batteries. Provides 1,500 cranking amps (750 ca, ea.) and 176 Amp Hours. Have averaged 10 years of life over the last two sets of batteries?
 
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dingbat

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It is not that they wont wirk, they will as you have proved...however the battery life is greatly reduced when not used as they are designed.
Sources please…. Not my experience at all
 

nola mike

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It is not that they wont wirk, they will as you have proved...however the battery life is greatly reduced when not used as they are designed.
Using a starting battery as a deep cycle will shorten its life but not necessarily vice versa.
 

jimmbo

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Deep Cycle Batteries are not designed to repeatedly provide Heavy Current supplies for more than very short periods. I suppose several hooked together in Parallel, would overcome that, then the issue of Equally Charging them configured like that will rear its Head.
 

nola mike

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Deep Cycle Batteries are not designed to repeatedly provide Heavy Current supplies for more than very short periods. I suppose several hooked together in Parallel, would overcome that, then the issue of Equally Charging them configured like that will rear its Head.

They're not designed for that and aren't as good at it, but that's not the same as a shortened life span.
 

RGrew176

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My experience differs a bit. I previously owned a boat that had 4 batteries. I had to replace all 4 batteries during the 2003 season. I installed 4 Sears DieHard group 27 batteries. When I sold the boat near the beginning of the 2011 season all 4 batteries were still going strong. That is 8 years and still going. Of course the batteries were maintained as they should be. Truth is after year 5 each spring the first time I fired up the boat I wondered is this the year the batteries don't make it but they did.

I am not recommending one way or the other but just how many CCA's do you need to start and run a boat during the summer. It's not like I was cranking over the engines at 0* F.
 

airshot

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Sources please…. Not my experience at all
I worked for a battery mfgr for a few years, that comes right from the engineers at Johnson Controls battery dept! Just because a few folks have sucess does not mean the majority will. In my 60 years of boating I to have had small sucess using deep cycle batted for starting small engines, but when they get used for big amp draws on larger mtors, they have proven to not last long. The high amp charge rate from an alternator also lessens there life.
 

nola mike

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I worked for a battery mfgr for a few years, that comes right from the engineers at Johnson Controls battery dept! Just because a few folks have sucess does not mean the majority will. In my 60 years of boating I to have had small sucess using deep cycle batted for starting small engines, but when they get used for big amp draws on larger mtors, they have proven to not last long. The high amp charge rate from an alternator also lessens there life.
My mother's best friend's husband told me so...
 

dingbat

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I am not recommending one way or the other but just how many CCA's do you need to start and run a boat during the summer. It's not like I was cranking over the engines at 0* F.
You are correct….CCA is calculated at 0* F. MCA is calculated at 32* F. MCA rating is 133% of CCA rating.

In theory…. “Actual Cranking Amps” at 70F would be 166% of CCA

Here is a list of OEM recommended battery sizes.


Most grp. 24 and 27 batteries are rated in the 600-650 CCA range, which according to the chart above, mets specification for all but the largest motors on the list.

The interesting part is that most so-called “Starting” batteries do not met the RC and or AH specifications of the larger motors on the list.
 

Lou C

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I’ve used Deka gp 27 dual purpose conventional batteries for years and I usually get 7 years out of them. Thought of going with AGM but not sure if the extra cost is worth it.
 

JimS123

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I’ve used Deka gp 27 dual purpose conventional batteries for years and I usually get 7 years out of them. Thought of going with AGM but not sure if the extra cost is worth it.
Someone told me they were worth it so I switched. Cars, multiple boats, etc. Then, I found out they weren't. With Autozone wet cell batteries I'm getting 8 years or so. The AGMs gave me less than 6.
 
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