Batteries

[Sandero]

I am facing a battery replacement as the two current 8D agm batts seem to have come to the end of their service life.

We use Shiva for weekend live aboard and one extended cruise in the summer in NE waters. We are planning to retire aboard in about 6 years or so.

I have a MaxCharge 614 w/ a 120 amp alternator and a Link 20.

Questions for the esteemed members of this forum are:

1. Is there any new battery technology which I should consider... Price point being a consideration of course....?

2. If I use existing technology... and don't want to deal with topping up water and out gasing, should I stick with AGMs?

3. Should I consider smaller batts... even fewer AH capacity or maybe the same AH capacity with more (smaller) batts?

[Kettlewell]

You're going to get a million different opinions on this, but I will throw out my two cents. You can't beat the value of traditional wet-cell deep cycle batteries, and probably near the top of that group in value are golf-cart sized 6-volt cells. Some people go so far as to use Sams Club or Costco 6-volt golf carts, but I think something like Trojan T105s are near the maximum value you can get in boat batteries. It is a lot easier to lug these around, they are replaceable almost anywhere in the world, they last plenty long if watered. That last item might be a killer for some people--for example, if you leave your boat someplace hot for long periods of time you will need to have someone check the water level periodically. AGMs are the latest greatest thing, but they do require much stricter charging regimens, and they cost a lot more up front. You have to really study up on how to best treat them to get the maximum life out of them, and if you can do it, I suspect their initial cost can be somewhat recouped. But, in my experience, stuff happens on boats, and inevitably some piece of charging equipment will fail at some point and if you trash a battery it will be very difficult to replace and very expensive if you are in the middle of the Pacific or someplace remote.

[sailorboy1]

I feel if you aren't plugged into shore power during the week I don't feel you should get the AGMs. I think you are just tossing away money in your use by buying something fancier than wet cells.

Why did you have so much battery capacity? Not that having more is really an issue

I use my boat like you and last week went though the same thing. In the end I replaced my 2 4Ds with 4 golf cart batteries for the price and use etc (was a lot easier installing a 60# battery that it was to remove a 110# one).

I'm going let all the experts that are about to come out in replies to do the long "explanations"

PS - my batteries have never needed water in the past year. They probably only really gas off is I have to motor for 10 years because I went somewhere and there wasn't any wind the next day to came home.

[Bash]

Originally Posted by defjef

We use Shiva for weekend live aboard and one extended cruise in the summer in NE waters. We are planning to retire aboard in about 6 years or so.

?

If you are going to cruise in six years, you will probably want to start off with fresh batteries at that point. If so, less expensive batteries that will not last much more than six years make sense.

[sy_gilana]

New Battery technology is not "here" yet. I am on my third set of Trojan T105's. Got 7 years out of the others sets. I have 12 in a 3x4 config to 24v.
Failure was my fault both times, a dry cell, resulted in charger overcompensating. I often visit the battery dump in boatyards in order to see what is being dumped and the date code on them. I am very happy with the T105's again. The volume density/elect capacity is good. Best of all, if you divide the capacity by price, you will get a dollar per amphour value. This is very illustrative. Next, divide the price by the days of service, to get a TCO (total cost of ownership) you will be surprised.
My friends who put in the BEST of the BEST, and paid through their nose, now have 8 year old batteries, they are no-where near as good as my NEW wet cells, and my twice-replaced bank is STILL cheaper than their 8 year old bank, that they don't want to change because the mortgage is not paid on them yet.
I am now adding a automatic watering system to avoid a repeat of my failures, investigate this (Trojan Web Page).
Do NOT let them discharge, (ie when the boat is unoccupied be sure there is some trickle charge)
If they are unevenly heated, change their positions every 6 months.

[sogin]

I agree you will get many answers. I don't own stock in battery manufactures but simply relate that we operated our boat in a similar fashion - mostly weekends and one extended cruise each year. We also had access to shore power but rarely used it except to freeze water in a few gallon jugs prior to departure on one week trips. Our original batteries were lost to improper maintenance by the boat yard over the second winter we owned the boat. I replaced the battery charger and installed AGM's. They lasted 12 years before we sold the boat last year and they seemed to perform quite well. I especially liked the fact that the AGMS could be fully recharged relatively quickly using a 100 amp alternator.

[rebel heart]

For whatever it's worth, "dealing" with my wet cell trojan t105's means filling up the water every few months and I'm typically in the battery compartment that often for some reason anyway. Takes maybe 20 minutes? The gassing issue, unless the compartment is truly sealed, really isn't an issue.

I have a couple of gallons of distilled water onboard anyway for engine coolant mix.

[Sandero]

Thanks for the replies... One other consideration is the battery compartment is painted marine plywood and that does not like battery acid spills which I did experience a bit when I had some wet cells for several years. As I do have a programmable smart charger and don't ever use shore power the charging is from the alternator or 110 watt solar cells which keep the batts topped up on the mooring.

I clearly don't need the capacity I have at present and this was set up for live aboard cruising where I used an SSB daily... for driving the Espar in the Fall. Going to LCDs will knock down the lighting draw, but not the other equipment.

Maintenance free to me is not having to be concerned with adding water. The install weight IS a concern, but that's a one time nightmare and it's over.

I'm thinking reduced capacity AGMs might be the best approach now.

[sailorboy1]

[QUOTE=defjef;879501]
Maintenance free to me is not having to be concerned with adding water. QUOTE]


Well you have answered your orginal question as that leaves AGMs and gel. Since you have solar panels your AGMs I think would be good as the batteries are going to fully charge during the week when you are away which 0other than the cost is the issue with them.

[DeepFrz]

Maintenance free to me is not having to be concerned with adding water.

Well you have answered your orginal question as that leaves AGMs and gel.

Or use the Water-Miser caps. Doesn't completely eliminate watering but reduces the need significantly.

[Sandero]

My PowerTech 8D's didn't seem to have much capacity left. They were 7 yrs old and so I replaced them. They sat on the dock and the tech guy decided to test them with some battery load testing device after sitting there for a week. "They're good he reported... the gauge needle goes right up into the the green".

I was about to bring them to the scrap yard and sell them for the lead... about $90 for the pair... but am wondering if there is some use for these batts... (not for on board).

Any suggestions?

[barnakiel]

I like the regular AGMs for the house and the toilet rolls AGMs for starting.

As long as the batteries are of managable weight and shape I prefer fewer bigger batteries to many smaller units.

At least one boat I sailed on had 2 Volt units arranged to the proper voltage. The units were (methinks) Vetus gel.

One boat had an emergeny Lithium (Ion?Polymer?) battery that was always full and placed high above high water mark. This battery was reserved for dire emergency comms use only. Owner's fancy, but I liked that.

b.

[Fuss]

[QUOTE=defjef;879501]Maintenance free to me is not having to be concerned with adding water. QUOTE]

All batteries require careful monitoring of the discharged and charge status, to ensure they are not discharged to much and to ensure they remain discharged for not too long and to ensure that they are recharged to an acceptable level and to ensure they are fully charged every few weeks.

This is quite a bit of monitoring and maintenance

Some batteries additionally require an equalisation charge every so often

Wet cell batteries require water to be added every so often.... a minor bit of maintenance in the grand scale of battery maintenance.

There is no such thing as a maintenance free battery.

[Sandero]

Update...

Here's the new battery installation. I picked up a pair of UB8D 8D agm (250 ah e/o) from an online vendor (no shipping charges) for $850 pictured on the shipping pallet after being unwrapped... and installed with the old charging / battery maintenance gear re installed with some new wiring and fuse holders. On the left are the fuses for the Espar Heater and TruCharge20, and the start battery sense for the Link 20 (start battery in a separate compartment just to the left not pictured). The center panel is both a battery hold down and a mounting panel for the Sulfator, Echo-Charge and the PV14 solar regulator and associated fuses. On the far right is the Link 20 shunt, the neg and pos busses for the gear noted.... and 2 fuses for the Link 20, main power and sense for the house bank. A entire day of wiring/installation. The battery box is below the berth in the aft cabin.

Let's see how these new batts do.

[Hyprdrv]

YOU want to talk Batteries??
This is a shot of my propulsion pack, 144V, 12 AGM Bats with Balancer system and PakTrakr monitors. Add 3 House Batteries and 1 Genset dedicated battery for a grand total of 16 bats. A lot of weight but then I have used around 30 gal. of fuel the last 3 years. TOTAL.
Your installation is one to be proud off, very nice. Question, I assume the Echo is for the start battery for the motor? Did you have to run a ground to the start battery as well as the hot wire?
Very little was said about the LifePo4 Batteries in this string. Something I will be going to in the future for the weight reduction (1/3rd the weight), about double the available energy at 1/3rd the charge time and should last 3 times longer. Their also about 3 times the cost of the AGM's at this point. But in 5 or 6 years the cost will be down to something more palatable.

Steve in Solomons MD
Lagoon 410 SE