Lead acids dying. What to replace with?

[sparrowhawk1]

Originally Posted by skipmac

After looking at all the battery types this is where I ended up. I really, really like the idea and benefits of the LiFePO but, like you, I have too many other things to deal with at the moment to learn how to pamper a new kind of battery. Also, if you screw up it will be a very expensive mistake, a couple thousand or more.

From all I can learn, a standard FLA, 6V golf cart battery will put up with more abuse than most other battery types and if you do manage to kill one they're the cheapest to replace.

+1 it would help if in the thousands of posts on the liFePO batteries a wiring diagram was shown. And for you gurus please don't tell me to do my homework I've been studying this for about a year and have a basic understanding but I want it in black and white before I make the plunge

[Maine Sail]

Originally Posted by Canibul

People on this forum told me that I should expect some battery issues after lightning fried just about all the 12 volt systems on board. Two years later, they're failing. 105 AH lead acids.

So, I need to replace them. What with? Anyone know of any clear winners in the battery replacement game? We can probably buy more deep cycle lead acid batteries locally at a huge cost, or could import what we want knowing it will take a week or two to get here.

Is there any way a new Outback MPPT could fry batteries through a stupid setting on my part? I'd hate to buy four new batteries and then find out the solar sytems are cooking them away.

Most 12V flooded batteries, in the group 24, 27 & 31 are really deep cycle imposters including the Trojan 12V G-24, G-27 & G-31... This means they are labeled as deep cycle but are really not much more than a label when compared to a GC2 6V.

Some brands will give more "cycles" than others in these group sizes but none really compete directly with a 6V GC2 in terms of cycle life.. As an example Trojan rates their 12V SCS series at roughly half the expected cycles as their own T105/GC2.

When buying batteries it is best to be cognizant of the fact that you are not just buying Ah capacity you are buying cycle life too. May boat owners often over look the cycle life...

There are 12V golf cart batteries such as the Trojan T1275, and they do have the same cycle life as a 6V, but they are also taller, like the 6V, and a built to use the same plates as a GC2 battery. Most G-24, 27 & 31 flooded batteries simply do not have the plate thickness or cycle life that a GC2 battery does.....

For example in the Deka / Sea Volt / West Marine line you have three versions all in the same case. Starting, Dual Purpose and Deep Cycle G-24, 27 & 31 12V batteries. However they are only really deep cycle when compared to the starting or dual purpose batteries with which share the identical case. They are not "deep cycle" when compared to a 6V GC2 or other purpose built deep cycle batteries.

Here's the data across the Deka / East Penn / West Marine line up:

Flooded Batteries - Group 24, 27, 31 & 6V GC2

12V Starting - Cycles to 50% = Not Rated
12V Dual Purpose - Cycles to 50% = 200
12V Deep Cycle - Cycles to 50% = 350
6V Golf Cart - Cycle to 50% = 700-1000


*Note: The above are LAB RATED cycles. Expect at least 50% less in the real world..


As one can see the 12V "deep cycle" battery is only a "deep cycle" when compared to the starting or dual purpose batteries it shares a case with.

If you absolutely must buy a 12V G-24, 27 or 31 buy the deep cycle version. In many cases this is all that will fit so a battery such as a US Battery DCXC or the Trojan SCS series will generally be about the best you'll get.. It is easy to see that these are not deep cycle when compared to a purpose built deep cycle battery.

AGM batteries like Odyssey and Lifeline, in the G-24, 27 & 31 are deep cycle when compared to other deep cycle batteries in their respective line ups. Most flooded batteries, not so much.

The only batts that have lab rated cycles the same or close, to their own brands 6V batteries, are Lifeline and the US Battery DCXC 12V series (at least those are the US Battery claims).

I know of no other brand that will rate their G-24, G-27 or G-31 at even half the cycles of their GC2 6V batteries. The 12V Deka / East Penn / WM product is less than half the rated cycles of their own 6V batts...

So it it not just the Ah capacity that winds up being cheaper it is also how long of a life you get that counts too.

In the abusive marine environment real world I do not see double the cycle life from 6V GC2 batts but I do see longer life, often measured in years. This longer life coupled with GC2's already being less money than 12V, Ah's to Ah's, means a much lower $$ to watt hours or $$ to lifetime Ah's comparison.

If you can fit the height of 6V flooded batts they are a tremendous value and tough to beat. If you can get to L-16's (considerably taller) even better....

[Ex-Calif]

Originally Posted by Maine Sail

Most

In the abusive marine environment real world I do not see double the cycle life from 6V GC2 batts but I do see longer life, often measured in years. This longer life coupled with GC2's already being less money than 12V, Ah's to Ah's, means a much lower $$ to watt hours or $$ to lifetime Ah's comparison.

If you can fit the height of 6V flooded batts they are a tremendous value and tough to beat. If you can get to L-16's (considerably taller) even better....

Glad you posted that - It was going to be my next observation.

There is a lot of, "My experience" etc. but not much real world data.

Life cycle cost is the number - we earn by calendar days and would like to know what does my "system" cost per day - If one wanted to overthink it one could probably set up a spreadsheet to calculate the several to many variables.

Purchase$ + Maint$ / life in days.

In terms of cycles to 50% one would have to evaluate how often one goes to 50%. If one has a badass charge system and rarely sees 50% one may convince themselves they don't "need" the extra cycles if it involves higher purchase$ & installation complexity.

Maintenance is a big deal for a lot of people - some love to futz with their batteries and add fluid, hydrometer checks etc. Some want them in the bilge minding their own business for 5-7 years (I suppose that is why AGMs are called maint free)

I don't think there is a one size fits all strategy for all boaters and that one needs to evaluate their own needs and circumstances.

One "for example" consideration - I have space for 4 battery "footprints" - If I go 12V I have 4 redundant 12v supplies. If I place 4 x 6v I only have 2.

If one 12v battery goes down I can cut it out of the system until I can replace it losing 1/4 of my capacity not 1/2.

If I had space for 8 footprints 6V makes more sense from a redundancy standpoint.

I am not advocating one way or another - just musing and (as usual) raising counterpoints.

The weekend boater, the vacation tripper and the liveaboard "off the grid" person all may have different answers to the same question.

[Ex-Calif]

Originally Posted by DeepFrz

Not unless they have a charge controller built into them and I don't believe they do. You can overcharge (fry) your batteries if they are fully charged and the wind picks up. Read Maine Sail's article on whether or not you need a solar charge controller.

I think you are addressing the elephant in the room. Before canibul buys batteries he needs to know most probable cause for the current failure.

If his battery monitoring system is set up right wouldn't the windgen supply voltage be wired in where it can be measured? And if it is overcharging shouldn't he see the higher than desired voltage &/or amps on the DC buss meter??

I am not convinced lightning killed these batteries.

[alamoana]

I recommend Rolls Surette series 4000 batteries. Been on the hook without shore power for 12.5 years on the same set of 4 x 275 AH batteries, with no shore power, nor solar. Just alternators and one hour per week of genset. Just 3 months ago I tossed one battery because continuos low reading on cell 1, but the other 3 are running just fine. They were pricier than other brands but do not believe many others would have lasted this long. Checking or adding water once a month and EQL once a year.


Sent from my iPad using Cruisers Sailing Forum

[Canibul]

I've got fiberglass tubs or trays in each engine room, with enough space for two of the group 31 plus enough room left over for almost a third one. Battery height is not a problem, up to several feet. Boat almost has standing headroom in engine compartments. I guess if I was five foot six, it would be standing headroom.

The Air X wind gen has been on the boat a long time. The manual says not to put a diode in line with it, as I remember, but I don't recall anything about solar controllers being needed or even mentioned as an accessory. The output of the wind gen goes straight to a two bar bus, with the outputs of the MPPT, a PWM and an ac charger all attached to the same bus. Two wires go from the bus (fused) over to the battery bank. The negative lead goes straight to the battery, and the positive lead goes to the 1, 2, 1+2, and off rotary battery switch. It is tied to the output post of that switch, which means I can apply the charging current of all combined charging sources to either bank of two house batteries, or all four. I typically just leave it in the 1+2 or combined position. All four batteries getting all the charging combinations. With that switch in the off position, no charging goes to anything. I installed the shunt and battery monitor, and it seemed to work fine right out of the box. It would be monitoring the sum of all charging. The only changes I made to the menu on the Victron was to input the AH, which was 420 AH a couple months ago. Then one battery fried. Now another. Both on the port bank.

The batteries have been too low to even run the VHF radio a number of times. They were at 9.5 volts yesterday. We lost all charging in the lightning strike. Took out both alternators and the MPPTs and an earlier battery monitor. In fact that was one of the fires in the engine room after the strike. What a lot of fun that was for a new boat owner.

[colemj]

Originally Posted by Ex-Calif

I think you are addressing the elephant in the room. Before canibul buys batteries he needs to know most probable cause for the current failure.


I am not convinced lightning killed these batteries.

His batteries were off-brand regular 12V car-type and are 4 years old. My money is on them having died of old age. Maybe helped along by the non-ideal charging conditions inherent with cruising boats.

I'm pretty sure the AirX is internally regulated. Everyone I have seen shuts down when the batteries are full.

Mark

[Canibul]

Okay. Y'all convinced me. I listened to Mark's advice. I just returned from local NAPA store, where I found that they still had 9 golf cart deep cycle batteries in stock in the warehouse. I didn't have any choices as to what types of numbers, it was buy some of these or import. I did read of someone finding their ideal battery in Florida for $ 135 each. Well, that ain't me. And this isn't Florida, so they were considerably more expensive than that but I bought four of them.

WHat do I use for AH rating on these things? The old batteries said 105 AH right on the label. IF anyone knows, these are NAPA #8144. I read on a golf cart forum that in 2010, at least, they were made by Exide and are the same as the Exide 3600.

Probably not the best choice, but they were here and I grabbed them. I just wasn't comfy thinking bout my boat in the water with nothing to run the bilge pumps....

[colemj]

These types of batteries are pretty much close together in capacity. If they weigh 55-70lbs, then they will be around 205-225Ahr, give or take a few. If they are rebranded Exide, they will be 220Ahr.

Edit - I just looked them up - they aren't the Exide GC-series. It appears they are 186Ahr.

Mark

[azsailor12]

Air X site says it has internal regulator.

[Canibul]

So my bank goes from 420 AH to 880 AH?

[Canibul]

Originally Posted by azsailor12

Air X site says it has internal regulator.

Yeah, I read that too. They have battery overcharge protection built in. Also read some comments by various people saying they were removing the internal regulators and wiring them directly and would just manually disconnect the AirX when their batteries are full. I don't think these were cruisers. Makes me wonder what I've got. IF the internal regulator went bad in an Air X, would it then keep charging fully charged batteries or does output go to zero?

[colemj]

No. When you connect batteries in series, you only get the single Ahr rating of the batteries, but at a higher voltage. So two of them in series will give you a 12V battery of 186Ahr.

In parallel, you maintain the voltage but increase the capacity by the number of batteries in parallel. So your two series pairs in parallel will give you a 12V bank of 372Ahr.

Mark

[azsailor12]

If the internal regulator failed, I suppose it could go either way, but more likely you would see excessive voltage on your panel.

[Canibul]

well damn. That sucks. especially at $ 188. each. So I lost capacity, and it sounds like I need to figure out how to tell if this AirX is working right.

Just goes to show ya......it's always something.