Batteries - How Old is Too Old...

[Loren Beach]

I have a couple of Trojan T-145's for the house bank. Installed new in June 2001. Anyone want to hazard a guess as to when to replace them, "just because?"
This summer, according to The Plan, we will go up the Washington coast to the rendezvous and then wander the boat around Puget Sound for a few weeks before returning to Oregon and home.
I would hate to have to replace these heavy batteries while out cruising, for equal reasons of convenience and cost.
They have been on "float" on a Statpower 20 shorecharger when at the dock, and do not have many "deep" cycles on them.

Sidebar: I once thought that quality batteries had very very long lives, but my 12 volt Trojan AGM starting battery died last summer. And it was new in 6/01, too. To somewhat reassure the experts, my two types of battery chemistry are not (normally) electrically combined. The AGM lives the life of a hermit, under the aft cabin berth, and waits patiently to start the diesel and accept a 20 minute alternator top-off, and then returns to contemplating its place in the universe.

I realize that there is no precise answer for the house bank question, but still... your collective experiences are always helpful.

Loren in PDX
Olson 34 Fresh Air

 

[Tom Metzger]

Two good answers

Loren - I can offer two answers from my experience:

Emergency generator suppliers who recommend lead acid batteries for starting gen sets that have to start when needed recommend changing out starting batteries every second year for reliability. They are dealing with inexpensive truck starting batteries, and the cost be damned as long as the generator picks up the hospital operating room load within seven seconds.

Deep cycle batteries used for the house bank on sailboats do not have a clearly defined end of life. As they run out of life they need to be charged more often; they do not die catastrophically as do starting batteries.

Before going on an extended trip it behooves you to test the batteries to be sure that they have sufficient capacity for your trip. Let the batteries run the fridge and other loads at the dock for a day or so to see what is available. You want to avoid surprises while cruising.

 

[Mike.Gritten]

Loren,

we live aboard our boat and have done so for almost 3 years now. When we first purchased her, I asked the PO about the Trojan T105's (2) that we had for a house bank. He said that they had been installed new, by him, in 1997 (felt marker pen on the batteries themselves back up his memory). The boat had a new statpower 20 charger installed shortly after, according to the PO. They were working just fine when we replaced them with new T105's last year before making the trek down to Port Townsend to meet all you fine sailors. That would make around 8 years of service - light duty for the most part as we are at the dock most of the time.

 

[rssailor]

Cycle the batteries

Loren,
Do you have a link meter? If not, just leave a light or two on for twenty four hours and then after that shut em off and measure the battery voltage at the terminals with a good digital volt meter. If you still read above twelve volts you should be good. Shame on you for mixing battery types, and you should know better. Also my experiance with AGM batteries is that buy the (concorde lifeline) no one else seem to make as good an AGM. Ryan

 

[Chris Miller]

Fwiw...

A diesel systems guy in Annapolis that we have been consulting on some of our systems says: "batteries last 3 years if treated well, anything past that is a gift" I asked him about gels and agm batteries, his answer was, "let me reiterate... batteries last 3 years if treated well, anything past that is a gift"
This man isn't in the battery selling business that I'm aware of, and is held in pretty high esteem by my surveyer buddy in town.
Just what I've been told- take it for what it's worth.

 

[Tom Metzger]

Leaving a light on for twenty four hours is not a realistic battery load test for Loren or most of us with refrigeration. That would be about 24 amp hours on 200 +/- ah battery bank. On my boat I use 50 to 75 ah per day which I consider minimum time between recharging. Other people should have different standards depending on their usage. The test should match the usage.

There is nothing wrong with having multiple battery types on a boat. I use flooded cells for my house bank and a zinc-air cell in my hearing aid. I don't mix the different technologies together so there is no problem. The same is true for starting and house banks. As long as you don't charge them or discharge them together there is no problem. For most of us that charge the batteries together it is a serious problem.

 

[u079721]

What I did.....

I was faced with this question a few years back when my original Trojans were 5 seasons old. My impression is that properly maintained flooded batteries can last up to 10 years, so I wasn't expecting to need new ones.

The the local advice I got was to first equalize them, then do a load test, and finally get the specific gravity in each cell. In my case the load test wasn't terribly helpful, in that the batteries had lost some capacity, but I hadn't done the baseline test when they were new for comparison. But what caused me to buy a new set for the boat was having unequal specifc gravity between the cells. I can't remember the exact difference, but there are some suggestions in Calder's book on this topic. If the specific gravities had been equal I would have kept them.

So....at least a specifc gravity test is one way to find out that your batteries are on their last legs.

I'm still not sure that good batteries shouldn't last more than 5 years. But if I had a big cruise coming up, new batteries would be cheap insurance compared with buying them along the way.

 

[rssailor]

Tom,
Yes only a discharge of 24 AH is not a meaningful test, but depending on what kind of lights you have, like a normal incandesent light bulb will draw around 2Ah an hour and if you have on two of those, the amp hours will add up. If it is a different kind of light that draws very little, then yeah 24 hours is not enough time. Mixing battery chemistries on your boat in your house and starting bank is not a good idea due to the fact that a large percentage of boats have a 1,2, both switch and just switch it to both to charge all the batteries. With sealed technology batteries mixed with flooded cell batteries, this is bad news. Ok enough for now. You planning on using the hearing aid battery to start the engine (Just kidding)?
Loren,
Do you have DC refrigeration on board?

 

[Loren Beach]

Power and Confidence

As always, Ryan, Thanks for the commentary. And you others, too!
I have a 12 volt Frigoboat system that we pretty much keep running from spring commissioning until late fall.
I chuckled over the hearing aid battery comment, but really did read about a guy that managed to start his large OB engine when his only main battery died by wiring together every small radio and flashlight battery he had (and it was quite a lot) and managed to get the engine to turn over a couple of times and start...
[So Tom finally motors back to the dock and keeps saying: "What, I can't hear you!"]

This thread indicates that I can check the specific gravity of each cell, and then trade in my old batteries for a couple of new ones!

Interesting note - The same model Trojan (T 145) is nowadays rated at 260 AH (20 hour rate) compared to mine which were rated at 235.
Voodoo AmpHours? Makes me wonder...


Thanks again,
Loren

 

[Guy Stevens]

Hmmm So Many Variables So Little Time

Ok I was avoiding wading into this holy war, but here goes.

First off there is no "Time to battery death". There is well taken care of and not well taken care of. A single charge discharge incident can have a major effect on battery life.

All data of the approximately 30 boats I have data on is actual for time peroids that I could verify, in almost all cases I was the original seller and installer of the batteries. In a couple I was not, in those cases I have the seen the original sales reciepts or like from the customers as they wanted to know; "How long do my batteries have left?"

My experiences with battery banks From Worst to Best:

AGMS:
5 Boats: AGM's 3 Years max with correct charging, and no charge discharge incidents. Long Range testing into the South Pacific. Various, verified by me, charging systems all correct for the type. YEAH ONLY 3 YEARS. ( All these batteries were installed right after the Lifeline AGM's came on the market, maybe they have changed something by now?) Current testing on another clients boat that insisted against my recommendations to avoid AGMs is in process, will let you know next year if they break the 3 year barrier, and in 10 years if they meet my criteria. + See Note

STANDARD FLOODED LEAD ACID:
10 + Boats: Lead Acid Flooded, From Very expensive Rolls batteries, to Costco Cheapies Well Taken Care of Batteries without any charge discharge incidents: 10 Years.
10 + Boats: Some minor Charge Discharge Incidents 5+ Years if the incidents were early on in the batteries life.
3-4 Boats: Major Charge Discharge Incidents immidately after new battery installation. As short as 4 days, as long as a year. (In each of these cases, it was pointed out to the customer that the charging system was not correctly functional, and had killed the batteries. One quote; "We are only racing, not cruising, new batteries will solve the problem."
* See note

East Penn Gel Cell Batteries.
Note the Branding, very very important.
5 Boats: 10-15 + Years, One boat still owned by orignal owners which have same batteries for over 17 Years. **(See Note)
(One boat has verifiable data for East Penn batteries lasting for over 20 years, Installed in 1984 still working today. Although I cannot personally verify this claim)
2 Boats 5 Years give or take. Both failures caused by failure of charging equiptment, or manual override without sufficient monitoring, batteries were taken to over 18 volts. (One of the batteries in question an 8D showed signs of case bulging and had produced really noxious ordors for over 30 minutes. This battery was removed and installed in another boat, and lasted another 2 years before failing completely).

Those are my data points.....

* The 2 4D's flooded acid type that are in my boat currently were originally installed on a trawler in 1984, and Removed in Jan 2005 because another vendor stated they had "Weak Cells", although hydroed and load tested fine by me. Since they were free, they are in my Ericson 46 and have been doing light duty there since. Eventually East Pen Gell Cells will replace them.

** The boat which has the 17+ Year batteries is cruised and lived aboard extensively for a couple of years, then left dorment for a year or two, then cruised and lived aboard for several years etc.... The batteries are fully charged, then disconnected from loads and left in their battery trays on the boat. The boat is started first thing upon recomisioning, and the batteries are charged again. This is a very festidous owner, and the electrical system is meticulously monitored and maintained.

+ I have Used AGM's in a different vehicle setup where they worked better than anything we tried. We were trying to get some older american metal ready for extensive off road racing. None of the batteries we tried at the time could survive the pounding and heat that we needed them to. We were able to secure some Military AGM batteries and utalized them in the vehicles. The batteries were a sucess although we abondened the program because the broken parts for the trucks was WAY beyond our budget. These were pre-public availability of the AGM batteries. They were superior in their ability to withstand vibration, heat and shock. Couldn't tell you what their charge discharge cycles were, or how they preformed as deep cycle batteries, they only started big old V-8's.

For what it is worth.
Guy

 

[Tom Metzger]

If we are going to get into anecdotal "evidence" about battery life we had better throw in a little information about battery life.

If you want a battery to last a long time keep it cool. Send an AGM battery, or any other battery, into the tropics it will have a short life. Every 15*F rise above 77* will shorten battery life by half.

Also, tie it down securely, vibration shortens life by causing particles from the plates to fall off. Eventually they may fill the bottom of the case and short out a cell.

Buying a battery larger than you need will allow you to keep it longer before it fails.

Deep cycle batteries have a life measured in discharge cycles, not years. If you float charge a battery and don't discharge it, it will last virtually forever. Utility companies use their station batteries in this way and get very long lives, typically 15-25 years.

Buying a new battery of the same brand as one that you had a love affair with 15 years ago is false security because the battery technology and manufacturing methods and materials change and you are not buying the same battery.

 

[rssailor]

Good point

Tom,
You make excellant points. I am not trying to be critical of ya. Keep sharing the good info and enjoy that great boat of yours. Ryan

 

[Guy Stevens]

Temperature

Remember your charge curve should be changed based on the temperature. Correctly charging based on Temp is mandatory if you are not going to cook the batteries. If you are going to be changing lattitudes and locations you need a charger that has a temperature sensor, or you need to be meticulus about your temperature readings AT THE BATTERY.

I forgot to note that I have seen more flooded batteries killed by not being kept filled than any other battery death by far.

Guy

 

[Geoff Johnson]

Here is some data from the Wind & Sun folks (http://www.windsun.com/Batteries/Battery_FAQ.htm#Lifespan of Batteries):


These are some general (minimum - maximum) typical expectations for batteries if used in deep cycle service:
Starting: 3-12 months
Marine: 1-6 years
Golf cart: 2-6 years
AGM deep cycle: 4-7 years
Gelled deep cycle: 2-5 years
Deep cycle (L-16 type etc): 4-8 years
Rolls-Surrette premium deep cycle: 7-15 years
Industrial deep cycle (Crown and Rolls 4KS series): 10-20+ years

 

[evm]

Loren,

I have 4 t-125 in my house bank with a statpower-20. Our 2 boats have the same environment and charger and baring any mishaps we should be more like two peas in a pod. With that said:

I bought my batteries in 1997 so I could say that you have at least 2 years left of useful service all other tings being equal (of course t-125 and t-145 are not the same and I have 4 vs your 2)

I'm a strong belever in testing. (and a bad speller) So, you could turn on all the equipment that you have to simulate a worst case load on your house bank and measure the time to drop to half charge voltage. This would give you a meaningful amp hour delivered figure. You should also then check the recovery time. This of course would be better to do under engine charging as that is what I expect you will be doing when cruising,

The point here is not to measure the AH rate or acceptance but rather to see if the batterys can perform up to your needs and expectations. You will be comfortable or not comfortable with the results.

As a side note, should you buy new batteries you might want to get them before you head out just to eliminate the infant mortality rate.

Where would you buy new batteries? I bought mine at Interstate battery years ago. I'm thinking that I will replace mine in the next 3 years so. I would love to piggyback on a golf course that is replacing all their batterys....

-Ethan

 

[Loren Beach]

Battery thread Closure, perhaps...

May 2007, and it was time to consider our battery needs before going on vacation this summer. So I replaced the house bank (two Trojan T-145's). The local distributor sez that I was at the outside of the time in years that most of these average...

So we decided that it's better to spend some money here in town rather than take a chance on being on foot in some little port, trying to obtain 140# of new batteries from some stranger miles away.

I suspect that I gave up a potential year or two of twilight life in the old bank, but, oh well....

What with some friends at the YC helping me move the old ones up and out of the boat and the new ones back in, that's just one more reason to complete this bit of preventative maintenance under controlled conditions.

And that's the 12 volt news.

Loren in PDX