Battery selection

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the60gunner

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New guy here; Sold my boat, but a retired career mechanic who's worked with heavy dc. Don't want to intrude, but still involved, working with RV, solar, and other dc.
Saw earlier thread on trojan 105s vs. 105+ 6 volt deep cycle house/inverter batteries.
Any newer experience along the line of longevity?
 
Welcome.


As far as your question. I have not a glue. However I am sure someone will chime in.


Cheers.


H.
 
New guy here; Sold my boat, but a retired career mechanic who's worked with heavy dc. Don't want to intrude, but still involved, working with RV, solar, and other dc.

Saw earlier thread on trojan 105s vs. 105+ 6 volt deep cycle house/inverter batteries.

Any newer experience along the line of longevity?



Welcome.

I have no idea on the batteries, but there are some here that have lots of experience. I think that it would be really hard to compare the two unless the care and feeding of them was identical. Even if a boat owner had one, then the other on the same boat, it is highly unlikely that the conditions between the two would be the same.
 
Golf cart batteries, the Trojan T105 being one of the best examples, are true deep cycle batteries that can stand hundreds, maybe a thousand discharge/charge cycles if you don't discharge them more than 50% each time.

Dual purpose- starting and deep cycle batteries won't last that long.

David
 
We are very happy with our Firefly Oasis carbon foam batteries. Not cheap, but if you are out cruising and on the hook for extended periods of time they are fantastic.
 
You need to get specific in your questions.

Flooded batts win for robust longevity, less fuss in charging requirements and value, limit discussion to those?

How big a bank in AH?

Longevity can be increased by spending a lot more per AH, but most are willing to replace the bank a bit more frequently to save money up front.

The biggest up front investment may be cheapest per year, if you're keeping your setup for decades.

A minor example, but price regular T-105 vs the RE variant in your area.
 
My last set of four Trojan 105's lasted 7 years in use to start my massive Volvo TMD31A and serve as house banks so I'm very satisfied with the quality of the Trojan 105.
 
You need to get specific in your questions.

Flooded batts win for robust longevity, less fuss in charging requirements and value, limit discussion to those?

How big a bank in AH?

Longevity can be increased by spending a lot more per AH, but most are willing to replace the bank a bit more frequently to save money up front.

The biggest up front investment may be cheapest per year, if you're keeping your setup for decades.

A minor example, but price regular T-105 vs the RE variant in your area.

I was always under the impression that sealed AGM batteries last longer than lead acid flooded.

Also, if the batteries are in an occupied space and outside the engine room, sealed AGM are safer.

I find Lifeline to be good ones. Expensive, but worth it.
 
60gunner, Welcome to the forum. I am in the 6V golf cart battery camp. Last a long time, very little maintenance and relatively cheap. If a pole was done I would expect well over 50% go this route.
 
I was always under the impression that sealed AGM batteries last longer than lead acid flooded.
Not overall. Top quality like Lifeline yes if very well treated.

But Rolls/Surrette go even longer in those perhaps unrealistic conditions.

FLA withstand normally abusive conditions, do not require the same precision charging gear, and you can get accurate SoC with a hydrometer.


Also, if the batteries are in an occupied space and outside the engine room, sealed AGM are safer.
Both outgass and should be vented, AGM less so, but then fluid can't be replaced.

I only recommend AGM when the install space requires it, or high CAR is required.
 
I was always under the impression that sealed AGM batteries last longer than lead acid flooded.

Also, if the batteries are in an occupied space and outside the engine room, sealed AGM are safer.

I find Lifeline to be good ones. Expensive, but worth it.



Not sure that AGM will last any longer than flooded, and likely the other way around. However, it seems to me, as a rank amateur, that what determines longevity is several things:

1) Typical Depth of Discharge. The lower the DOD (or the higher the State of charge) before recharging, the longer the life of the batteries.

2) Adequacy of charging. Are the batteries regularly getting fully recharged?

3) Number of times the batteries were abused, i.e. very deep discharge, rarely recharging fully, too hot, too cold, not replacing water etc...

The only way I think you might expect AGM to last longer than flooded would be that AGM have a higher rate of charge acceptance so maybe they will get more charge, more often than a FLA?

John can tell us.
 
At the cheaper end of the market FLA have a much greater, actually a huge advantage.

Most inexpensive AGM don't even rate as true deep cycle, even in 6V GC format.

Deka's Duracell branded line is a perfect example, brilliant value in FLA, very sub par in AGM.

But still better than most, really there are only four quality AGM makers in the US market AFAIK, and all are very pricey.

Sam's Club and Batteries+ sell the Duracell GC for ~$180 a pair, really can't beat that.
 
what determines longevity
Yes, all these and some others comprise "proper care".

AGM longevity suffers more sharply if any of these are compromised, FLA is more robust in a normal, less than ideal context.

Yes if high CAR is important, e.g. living on the hook minimizing burning dino juice, not enough solar, AGM can be charged much faster.

More of a concern with cruising liveaboard sailboats than stinkpots AFAICT.
 
Deka's Duracell branded line is a perfect example, brilliant value in FLA, very sub par in AGM.


Hmm, maybe I should have done more homework; put a pair of their AGM in my 22' CC about 6 months ago. So far they still work.
 
Absolutely, not saying they're actually **bad**, East Penn is a quality maker for sure, in the top five for FLA mfg.

Just that their AGM is not nearly as good for deep-cycling longevity as the top five AGM mfg.

But neither are **any** AGMs available at what consumers think of as reasonable prices.

Which is exactly my main point.

And would love to proven wrong, so many people are wanting "maintenance free".
 
You need to get specific in your questions.

Flooded batts win for robust longevity, less fuss in charging requirements and value, limit discussion to those?

How big a bank in AH?

Longevity can be increased by spending a lot more per AH, but most are willing to replace the bank a bit more frequently to save money up front.

The biggest up front investment may be cheapest per year, if you're keeping your setup for decades.

A minor example, but price regular T-105 vs the RE variant in your area.

Yes well cared for, a quality bank can last well over a decade

Not overall. Top quality like Lifeline yes if very well treated.

But Rolls/Surrette go even longer in those perhaps unrealistic conditions.

FLA withstand normally abusive conditions, do not require the same precision charging gear, and you can get accurate SoC with a hydrometer.


Both outgass and should be vented, AGM less so, but then fluid can't be replaced.

I only recommend AGM when the install space requires it, or high CAR is required.

At the cheaper end of the market FLA have a much greater, actually a huge advantage.

Most inexpensive AGM don't even rate as true deep cycle, even in 6V GC format.

Deka's Duracell branded line is a perfect example, brilliant value in FLA, very sub par in AGM.

But still better than most, really there are only four quality AGM makers in the US market AFAIK, and all are very pricey.

Sam's Club and Batteries+ sell the Duracell GC for ~$180 a pair, really can't beat that.

Yes, all these and some others comprise "proper care".

AGM longevity suffers more sharply if any of these are compromised, FLA is more robust in a normal, less than ideal context.

Yes if high CAR is important, e.g. living on the hook minimizing burning dino juice, not enough solar, AGM can be charged much faster.

More of a concern with cruising liveaboard sailboats than stinkpots AFAICT.

Absolutely, not saying they're actually **bad**, East Penn is a quality maker for sure, in the top five for FLA mfg.

Just that their AGM is not nearly as good for deep-cycling longevity as the top five AGM mfg.

But neither are **any** AGMs available at what consumers think of as reasonable prices.

Which is exactly my main point.

And would love to proven wrong, so many people are wanting "maintenance free".

John, you seem to have strong opinions on the subject and make recommendations as if you're an authority, but we know nothing about your experience or training. You've been with us a few months and have wrung up a significant post history in the electrical section. Can you tell us a bit about your credentials? Have you worked extensively in the industry or is this academic or book knowledge?

Who did you work for? Maybe we know some of the same people.
 
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No thanks, and not claiming any special knowledge that can't be found by anyone with decent google-fu.

I welcome clarifying Qs on any specific points I make, and of course welcome any constructive feedback, I learn lots of new stuff everyday from many with more knowledge and experience.
 
Before spending a cent on any batts , install a SOC , State of Charge , device.

This is the ONLY way you will know how deep you are discharging and how well you are recharging the house batts.

Here is one , there are many to chose from.


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    Products Brief Product Descriptions TriMetric Battery System PentaMetric Battery System Solar Charger Accessories News & Updates ...

 
I have 4 Interstate 6V deep cycle batteries (225 amp hours ea IIRC) running an inverter bank to run the fridge.
They are 5 seasons old right now and still working, but I have noticed they are losing some of their power.
I don't do anything special to them other than charge them at the dock, then with a Balmar/smart regulator when cruising.
 
Did you buy at Cosco? Wider range at the Interstate shop directly.

Good solid batt, actually Johnson Controls.

The Deka/Duracell FLA at Sam's & B+ are a bit longer-lasting and rarely more expensive.
 
A SOC meter is not a panacea, they have to be reset regularly to compensate for aging, etc. You have to be willing to do that.
 
A SOC meter is not a panacea, they have to be reset regularly to compensate for aging, etc. You have to be willing to do that.


I agree and since I am too ignorant/lazy to do a proper capacity test, it is just a guess as to what the total capacity of my bank is. I consider the SOC to be a WAG that is much better than just looking at voltage.

This is one of the reasons I am interested in installing a Balmar Smartgauge. Not that I understand how it work at all, but I think it is much more suited to someone like me, i.e. Ignorant and lazy.
 
A SOC meter is not a panacea, they have to be reset regularly to compensate for aging, etc. You have to be willing to do that.
Except for SmartGauge, one reason why it's overall more accurate than shunt-based monitors.

But IMO after a few years, a 20-hour load test should be performed anyway every so often to track their SoH decline, be prepared for replacement before unexpected failure.
 
Not trying to say SG is a panacea by any means, just that it is easier to use and more accurate.

Many also use an AH-counting monitor to supplement the SG for a more complete picture, SG can help to calibrate it as AH capacity walks down over time, and the shunt unit can be more accurate while charging or under high-amp loads.

FLA and a hydrometer can be another great tool for SoC.
 
No thanks, and not claiming any special knowledge that can't be found by anyone with decent google-fu.

I welcome clarifying Qs on any specific points I make, and of course welcome any constructive feedback, I learn lots of new stuff everyday from many with more knowledge and experience.

Are you saying you haven't worked in the industry and the advice you dispense is Google-based knowledge?
 
dhays,
I have had bad experience with Balmar's Smartguage. I have spoken to Balmar about it several time. With new batteries, fully charged showing 13.1v on the charger. The SG shows 86% SOC.
 
dhays,
I have had bad experience with Balmar's Smartguage. I have spoken to Balmar about it several time. With new batteries, fully charged showing 13.1v on the charger. The SG shows 86% SOC.



That is interesting. It is my understanding that it takes time for the SG to adapt to the system and accuracy improves over time. Has this not been the case?
 
Are you saying you haven't worked in the industry and the advice you dispense is Google-based knowledge?


I think John is saying that he would rather not discuss his professional experience in the forum.

Regardless of where he has gained the knowledge that have informed his opinions, I have found them to be helpful, informative, and they have concurred with other sources whom I have come to trust.

I have no professional experience as a rigger. However, I am pretty darn good with splices and my experience could be useful to others.
 
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