Batteries?

[Chris777]

Originally Posted by contrail

I have never heard of a golf cart with 8D batteries, and I was a golf professional for years! Since you eliminated golf car batteries (which are efficient, true deep cycle batteries), perhaps Logan was out of his depth recommending something out of his knowledge base.

I do agree with others that certain details need clearing up for the sake of credibility.

Who said there was a golfcart with 8D's?

[Sailmonkey]

Originally Posted by Chris777

Boys Boys, Please tak ALL factors in to play. I am limited in size and depth in my batt box. The only thing that fits is group 31 or 8D's. I am sure I could throw some car batts in there, but that is not what I want. AGM/GEL/FLA I really dont care, I wanted max amps (and yes 2X460=920) for my own reasons.!

Trojan 8D agm batteries are not 460 amp hours.

They’re 230 at the 20 hour rate.

460 is the reserve capacity.....this is not the measure that is used to define the “size” of a deep cycle battery bank.

http://www.trojanbattery.com/product/8d-agm/

If you treat them as a 920 AH bank, you’ll have really damaged/useless batteries in no time.

[Stu Jackson]

Originally Posted by Chris777

Boys Boys, Please tak ALL factors in to play. I am limited in size and depth in my batt box. The only thing that fits is group 31 or 8D's. I am sure I could throw some car batts in there, but that is not what I want. AGM/GEL/FLA I really dont care, I wanted max amps (and yes 2X460=920) for my own reasons. If someone disagrees with tha,t fine.... but dont ding the people that helped ME. Its a reputable company with a reputable product, at least around here. So just like everyone here tried to help me I was just trying to help back...... Sorry it backfired!

Chris, I don't think it backfired in any way.

I just Googled 8D batteries, and found Trojan's website.

Their 8D battery has 460 MINUTES in CAPACITY at 25 amps (load).

It has 230 ah (amp hours) at the 20 hour rate.

The reality is that you are simply confusing ratings numbers by not using the correct terms. You can't mix the numbers and the terms.

That is the purpose of Stu suggesting you read his excellent amps vs amp hours thread.

FWIW, 99% of us use the amp hours at the 20 hour rate when we're quoting battery capacity. The 1% get it wrong, over and over. This is just another case.

You bought 460 ahs worth of batteries. Not 920 amps (2 * 460), because that's not what is used either around the bar with friends or in any battery monitoring system.

Is this clearer for you now, perhaps?

[skipmac]

I think Stu Jackson identified the source of confusion, mixing minutes with amp hours (not amps). It would help the discussion and possibly avoid some of the dispute if you could understand and use the right terminology. Like shopping for a high performance car and mixing up horse power and rpm, it leads to confusion.

Deep cycle batteries the important spec is amp hours which in short hand, is how much electricity the battery can store. Amps is a measure of how much electricity is flowing out of the battery at one instant of time.

[john61ct]

Originally Posted by Chris777

No StuM he did not. You know what they say StuM? There is an a$$ in every crowd! I guess you are it in thi "crowd". I tried to learn, I tried to share whAt I learned and know. You aparantly is just another lonely flame thower.

I dont like to throw anybody under the bus, but when someone try's to take my experience and take it out of context, I will fire back!!

I'm sorry don't mean disrespect you, your experience with him, nor the guy.

But since you did end up with batteries **not actually designed** for your deep cycle usage, I agree with the others that you got bad advice and perhaps misinformation.

Not saying you got ripped off, maybe he just doesn't know the difference himself.

Besides your being misinformed as to their AH capacity.

Plus you also never gave a valid reason why you went with AGM, two of my posts gave better FLA G-31s that would have

fit the space

cost less

last longer

give higher total AH capacity.

So all in all, over a ten-year period you may have spent double the $/AH/year compared to going with a more optimal choice.

Likely that is no big deal for you from a big picture POV, but for others coming later to inform themselves, it is IMO important not to leave misinformation uncorrected.

[john61ct]

Originally Posted by Chris777

Boys Boys, Please tak ALL factors in to play. I am limited in size and depth in my batt box. The only thing that fits is group 31 or 8D's. I am sure I could throw some car batts in there, but that is not what I want. AGM/GEL/FLA I really dont care, I wanted max amps (and yes 2X460=920) for my own reasons. If someone disagrees with tha,t fine.... but dont ding the people that helped ME. Its a reputable company with a reputable product, at least around here. So just like everyone here tried to help me I was just trying to help back...... Sorry it backfired!

I think we have wasted a lot of our time here.

Either you have not been reading our posts, or at least not absorbing what we have been trying to communicate.

[StuM]

Originally Posted by john61ct

I think we have wasted a lot of our time here.

Either you have not been reading our posts, or at least not absorbing what we have been trying to communicate.

Quite! I give up.

Several very knowledgeable posters have helpfully pointed out inacurracies and misconceptions expressed by the OP and they've all either been ignored or insulted.

You can lead a horse to water....

[StuM]

Originally Posted by skipmac

Since you purchased a pair of 8D batteries one has to assume it was on the recommendation of the person you say knows his stuff.

Since you purchased them for house batteries then one has to assume Logan would know that a true, deep cycle battery would be the best option.

Not necessarily. In fact I doubt that a company called "American Pride Golf Cart Services" has any real knowledge or experience with marine installations or cruising boat house battery usage.

[kmacdonald]

Is anyone using the Trojan Solar Premium series with "Smart Carbon"? They claim 10 year life.

[skipmac]

Originally Posted by StuM

Not necessarily. In fact I doubt that a company called "American Pride Golf Cart Services" has any real knowledge or experience with marine installations or cruising boat house battery usage.

Actually what I meant to say was that Logan "should" know that a true, deep cycle battery would be the best option.

Either he didn't know that a true deep cycle was the best option or he thought his 8D was a true deep cycle (maybe but I'd say it's a very long shot) or he just sold what was easy. I'm trying not to be cynical and think he sold what made him the biggest profit.

Even if this is a real, deep cycle battery it is

1. An AGM which generally require a good bit of knowledge and understanding of charging and your system to avoid early death

2. They weigh about 60 Kg and are a huge pain in the posterior to move around. Good way to break something, like the boat or your back.

[kmacdonald]

I'll give my 2 cents on what makes sense and works for me. I like smaller banks and like to cycle to 80% DOD. They charge faster per unit of energy used since they will stay in bulk charge longer. (80% DOD to 20% DOD) They are lighter than a big bank. The energy needed to charge from 20% DOD to full can be easily accomplished with a reasonably sized solar panel. If the bank is ruined for some reason you aren't out an arm and a leg. A gourmet charge system isn't required.

[skipmac]

Originally Posted by kmacdonald

I'll give my 2 cents on what makes sense and works for me. I like smaller banks and like to cycle to 80% DOD. They charge faster per unit of energy used since they will stay in bulk charge longer. (80% DOD to 20% DOD) They are lighter than a big bank. The energy needed to charge from 20% DOD to full can be easily accomplished with a reasonably sized solar panel. If the bank is ruined for some reason you aren't out an arm and a leg. A gourmet charge system isn't required.

Very interesting idea. Of course most batteries will lose significant percentage of their life span discharging 80% but as noted, you can probably get by with fewer batteries and charge is more efficient.

[boatpoker]

Sorry to see Chris777 gone. This has been hugely entertaining. Hey Stu, it just goes to show .... You can lead a horse to water but you can't make him think

[contrail]

Originally Posted by Chris777

Who said there was a golfcart with 8D's?

YOU said you bought the batteries from the experts at American Pride Golf Car Services, in Bradenton. It follows that they know something about golf carts.

I said I never heard of 8D golf car batteries, leading me to the conclusion that they might not know as much about 8D batteries, which are basically starting batteries for big trucks, as you think.

And that is the connection.

[kmacdonald]

Originally Posted by skipmac

Very interesting idea. Of course most batteries will lose significant percentage of their life span discharging 80% but as noted, you can probably get by with fewer batteries and charge is more efficient.

It's economically less expensive in battery costs to discharge to 80% DOD.
Look at the Cycle Life Chart here: Solar Premium Line Flooded | Trojan Battery Company
The difference in cycle life between 20% DOD and 30% DOD is about 1300 cycles. The difference in cycle life between 70% DOD and 80% DOD is only 250 cycles. The graph and evidence clearly favors deeper DOD cycling. It is by far the most cost effective use of batteries.