Marine Battery Life

[jim_m5]

Yesterday we tried to take her out for a run and the she would not start. Batteries were dead. Fortunately I was in the slip. I tried to jump the batteries with a portable generator but it did not work. Ended up replacing both batteries. Batteries were less then 2 years old. These are Everstart Marine Batteries(i.e. 27DC-6, 12v, deep cycle, Marine Cranking 720) purchased from Walmart.

I leave the battery switch on 'both' unless we are staying over night and then I swith to battery 1 and keep battery 2 as the backup. Yesterday 1 battery was completing dead and the other needed a major charge. I replaced them both.

A few questions:

1. What is the expected life of a battery? I don't think we use the battery much.

2. What is the best method to employ on the battery switch?

3. The boat is on a lift and I have shore power always connected. I also have the AC Concerter on to trickle charge the battery. I thought this was the best way to prolong battery life?

4. Are these Everstart batteries a quality product? They were only $60 each. I would expect to get 3 years out of a battery, no?

Appreciate any tips on battey maintenance and power management.

 

[wingless]

My assuption is these are flooded cell batteries.

To maximize the life, keep them fully charged, maintained at about 13.8VDC, with the electrolyte at the specified level.

An inactive flooded cell looses about 10% state of charge per month, more in warmer temperatures. When that battery reaches about 50% state of charge, the sulfation rate increases.

Sulfation is permanent damage to the plates, decreasing capacity. So keep the battery charged.

All batteries, flooded cell included, are specified for a lifetime dicharge / charge rating. Beyond that the capacity is specified to be less than 50% and the battery is considered to be done.

A properly maintained flooded cell should give 3-4 years of service.

 

[Henry Boyd]

Jim

1. Battery Life depends on a lot of things, number of charge cycles, number of times it is run flat etc. I would think three years should be expected. The battery in my pickup failed last year after 7 years, and then only because the stupid GM side terminal fell off!

2. I leave the battery switch off when we are not using the boat, mainly because our GPS (Raystar 125) is on otherwise. Also Shutting the battery off reduces possibility of generating stray electrical currents and accelerating corrosion (we are in water all season). Remember the bilge pumps function regardless of battery switch setting.

3. Leaving the AC converter on may be the root of your problem. Not that it is a bad policy in general, but the 01 02 converters seem to have a higher than reasonable history of killing batteries. In fact replacing ours is high on the list of our replacement projects.

4. I can't speak about Everstart batteries, but at $ 60 a piece, and West Marine batteries running $ 80 to $ 140 each, it strikes me that sometimes you get what you pay for.

Henry

 

[tollycraft]

One of many things I have learned through this site is to check your battery levels at least once a month (more is better of course). Battery levels will drop due to charging. Batteries IMHO should last at least 3 years but that depends on how they have been serviced and the quality of the battery. You want to put a volt meter on your batteries now that their new and check to see if there is possibly a draw on them that you are unaware of. If you are unable to do this, get someone who is qualified to check this out,preferably a marine mechanic because if there is a draw somewhere, a marine mechanic knows what to check and will probably be able to fix while he's there (you have to pay for the service call already so solve the problem or at least find out what it is) As far as the battery switch, I leave only one battery on at all times but I dont require battery power while on the water as I fish mostly and during the daytime so don't require additional power for anything else like lights etc. Not sure how your trickle charger works but believe a shore power charging system that only comes on when the batteries call for it is the best bet. As far as the quality of batteries you purchased, I can't speak to that because I've never heard of them. I will make one suggestion though, Buy a battery load tester, best investment I've ever made. Very easy to use, will tell you the state of your batteries and also has the abilty to check your alternater to make sure your charging system is working. I'm in Ontario Canada and the cost was about $65.00. Good luck

 

[wingless]

3. Leaving the AC converter on may be the root of your problem. Not that it is a bad policy in general, but the 01 02 converters seem to have a higher than reasonable history of killing batteries. In fact replacing ours is high on the list of our replacement projects.

The ignition-protected charger on my '00 worked fine until is failed w/ the output transistor bursting into flames in my engine room.

Fortunately I maintain the vessel with only one or two of the three items required for combution.

This was replaced w/ the Charles 50A charger.

 

[jim_m5]

Guys thanks for the quick response. I was told these batteries are self-maintenance, meaning you do not need to add to the ectrolyte levels. In fact they say that if you do it will void the warranty.

 

[sbw1]

How long was the warrenty?

 

[jim_m5]

1yr replacement, 24month limited warranty. I earned $12 back per battery on the new purchase. I suppose spending a $100 every 2 years for batteres is economical?

 

[sbw1]

We used to get 4 and some times 5 years from a pair of high quality flooded cell batteries. The boat was simple and while it had shore power, I did not keep the charger on all the time and seldom plugged the shore power in. I did keep the batteries up and fully charged. As others have suggested, proper maintnenance and a decent quality product will easily get you 3 years of service and much more with a little care. I always replace them all when I have the first failure and they are nearing the end of their life.

 

[Four Suns]

If you anchor out a lot and are discharging your batteries by playing the radio and running a fridge, you may want to nuke the wet cell batteries and go with an AGM type battery. AGM's handle being run down much better than a wet cell battery and will last significantly longer for that type of application.

Also, if you've added a bunch of 12-volt electronics (like a high-amp stereo, brighter light bulbs in the sockets, inverter, bigger TV, etc.) and still have the original converter/charger, you can be running your batteries down even while plugged into the dock and be cycling them without really knowing it. That also will kill wet cell batteries. If that is the case, you may need to upgrade your converter/charger to handle the higher 12-volt needs and not cycle your batteries as much. Sea Ray only put a converter in at the factory to handle the 12-volt budget as it was built new.

Those are just a few things. I could only get 2-3 years on my D-size batteries in my boat and I switched them to AGM last year as I'm tired of losing clothes to battery acid and hauling D batteries that are made with kryptonite based on their weight.

 

[tollycraft]

If you anchor out a lot and are discharging your batteries by playing the radio and running a fridge, you may want to nuke the wet cell batteries and go with an AGM type battery. AGM's handle being run down much better than a wet cell battery and will last significantly longer for that type of application.

Also, if you've added a bunch of 12-volt electronics (like a high-amp stereo, brighter light bulbs in the sockets, inverter, bigger TV, etc.) and still have the original converter/charger, you can be running your batteries down even while plugged into the dock and be cycling them without really knowing it. That also will kill wet cell batteries. If that is the case, you may need to upgrade your converter/charger to handle the higher 12-volt needs and not cycle your batteries as much. Sea Ray only put a converter in at the factory to handle the 12-volt budget as it was built new.

Those are just a few things. I could only get 2-3 years on my D-size batteries in my boat and I switched them to AGM last year as I'm tired of losing clothes to battery acid and hauling D batteries that are made with kryptonite based on their weight.

As I understand it ( I could be wrong here so I am asking for some input) The AGM batteries require a slower charge. I have an original Sea Ray shore power charger that came with the boat. Is this charger suitable for AGM batteries.

 

[Four Suns]

I guess I have to ask "slower than what?" Don't confuse AGM batteries with Gel batteries. They are not the same even though both are lead acid and do not have a free fluid electrolyte (i.e. like a wet cell). The rule of thumb is that AGM batteries have charging characteristics about the same as wet cell lead acid batteries. However, they require voltage limited chargers which is what any modern smart charger/converter will give you. Overcharging or undercharging an AGM, just like a wet cell, will kill it. All I can say is you need to look at the charging recommendations from the battery manufacturer and see if they match the characteristics of the charger on your boat (I assume you have a manual?).

I don't know what Sea Ray put on as a charger back in 1988 but I would think you are up for some newer technology as this area made a lot of advances in the mid to late 90's for consumer applications. Even if you don't have AGM, you'll get longer life out of your batteries.

 

[sbw1]

AGMs are great. I'm into my 5th season now. When I put the boat away in October they showed no signs of degradation. I'm hearing some people are seeing 7 seasons with good results.

 

[Skuza]

We have gotten 5 years out of the current Sam's Club batteries. VERY occasionaly checked the water in them and only leave the AC converter on while we're on the boat.

 

[tollycraft]

I guess I have to ask "slower than what?" Don't confuse AGM batteries with Gel batteries. They are not the same even though both are lead acid and do not have a free fluid electrolyte (i.e. like a wet cell). The rule of thumb is that AGM batteries have charging characteristics about the same as wet cell lead acid batteries. However, they require voltage limited chargers which is what any modern smart charger/converter will give you. Overcharging or undercharging an AGM, just like a wet cell, will kill it. All I can say is you need to look at the charging recommendations from the battery manufacturer and see if they match the characteristics of the charger on your boat (I assume you have a manual?).

I don't know what Sea Ray put on as a charger back in 1988 but I would think you are up for some newer technology as this area made a lot of advances in the mid to late 90's for consumer applications. Even if you don't have AGM, you'll get longer life out of your batteries.

Yes I do have a manual and will check. I have no intentions of selling the boat so will check with my marine mechanic and see what he suggests. I do a lot of my own my own maintainance and repairs however I must admit I prefer to leave electronics alone do to my lack of experience, as I'm sure you can tell. Thanks