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House Battery Issue


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The cost of the one I posted above is $550. If your old battery had 2 shorted cells, its should not have produced 6v.

Resistance in cables is a moving target. The best I can say is that a cable can test 0 ohms at no load, and still be useless at any sort of load. It depends what the problem is. Sometimes it will show resistance with no load, more often not.

It must have a proper voltage drop test done to be certain.

If the cable between the batts was the issue, there should have been a noticeable drop in voltage at batt,but with alternator going and trying to compensate, maybe not...

As an aside, I'm doing an educational evening at Gulf Harbour yacht club on batteries and voltage drop testing in a couple of weeks. Free for members, small charge for non members. Bring your multi meter, hands on circuit testing. Date to be advised in next few days.

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Can you short a plate in a cell and not short the cell?

 

There are only 3 cells in the batt, so 2 shorted cells would stick out...

 

I need to clarify with the supplier if it was 2 shorted plates, or 2 shorted cells.

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what is the ball park cost for a logging system? I want to understand cost, verse a new set of batteries...

 

Fish, you may want to check whether your eTracer MPPT already supports logging.  If you only want to record voltage rather than remaining battery capacity or current draw/charge then it may be more economic to add a simple logger to record the stats for long term storage. 

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Thanks Farrari, you may be onto something there.

The etracer does have an RS-485 port and the manual refers to a remote meter MT 50 (as well as other stuff).

I don't need one of those flash battery capacity meters, but being able to record volts and batt temp would be ideal.

 

I've spoken to the retailer and supplier to get clarification of the fault, I will report back later on those details.

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The MT50 records solar energy, KW hrs etc. Not battery max charge/discharge and max/min voltage which is what you want.

IMO every boat should have a battery computer. Without one, you have no idea the state of charge of your battery. The one on the solar controller is so inaccurate as to be worse than useless, as it may lull you into a false sense of security.

To get an accurate state of charge from a lead acid battery requires it to rest (no charge, no discharge) for >10 hours. No one does that on a boat.

Most people discharge the batts much more than they think they do.... 

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So the problem has been confirmed now.

 

It is a 'lost comms' issue...

 

Someone in Auckland has an overcharged battery with bulging, the top has been cut off and the plates have deformed, with crumbling and black bits, which is all a sign of overcharging.

 

My batteries are sitting in the Albany depot of the supplier, and they've been wondering what to do with them... There is nothing visually wrong with them.

I did drive down there on the expectation of getting new batteries under warranty, then the miscommunication issue became apparent, we were talking about different batteries.

 

The supplier is going to do some capacity testing on them, and see if they can confirm why one is using more water / dry plates. They don't believe the connecting cable I was using would cause the issue.

 

The retailer is going to follow up on the 'lost comms' issue, and is of the view I should get new batteries anyway, just for the shagging around...

 

It just goes to show, you should not take what you are told for granted, and to ask for explanations... It was beyond me how anyone could describe my batteries as 'bulging', and the more I looked into the charging details and other items I had recorded, the more I felt like something was not adding up.

I could easily have spent another $700 on new batts, then spent the rest of this coming summer trying to find a phantom fault in my charging system...

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So the outcome on these house batteries is that I've got new batteries under warranty.

But I still don't actually know what was wrong with the old batteries.

 

They tested at 75% capacity on a load test. They were 20 months old, and had very little use. They were kept on a float charge via solar.

The supplier did say that 80% capacity was the spec for a warranty claim, and they felt that they could get the batteries back to that by reconditioning them, i.e. equalisation and pulse charging. The retailer, Burnsco, did lobby for a replacement under warranty, which I got. It does go to show the benefit of using reputable retailers.

 

The supplier did try telling me the batts were out of warranty, as their deep cycle batts only have 6 months. I kind of laughed at that and told him to look at the sticker on top of the battery outlining a 24 month warranty (I took photos of the batts before handing them over...)

 

The supplier hasn't done any cell chemistry checks, no hydrometer or any

thing, just the load capacity check. They have stated the warranty replacement is primarily for good will...

 

Does 75% capacity after 20 months sound normal / acceptable for FLA batteries?  I think it sounds like bollocks (i.e. not acceptable).

 

The supplier said its likely these batteries have suffered from lack of use. I aren't familiar with the issue (sure, I'd like to go sailing more, wouldn't we all). I thought most batteries died by excessive discharge, or deteriorate through cycling, the deeper the cycle the greater the deterioration.

There is a note in the Endurant Specification book (page 89, if you are still awake when you get there...) that "Once the battery is fully charged, it can be maintained by applying a 'float charge'. However it is worth noting that this float charge does cause some deterioration in the cells but this deterioration is often less than the damage caused by the batteries being left in an under charged state"

 

The supplier didn't think the cable I was using to join the two batts was an issue (he did check for corrosion etc on the terminals, and didn't find any). I gave full disclosure of the charging set up, including the internally regulated alternator. That didn't seem to interest them.

 

So how are you supposed to care for FLA deep cycle batteries? I'm a bit lost after this experience.

 

We aren't going to put the solar back on until we need it for cruising in the summer, so no float charge and no risk of over-charging the batts. For day sailing / winter racing the engine running time is high compared to the actual sailing time.

We will convert the alternator to a smart charger, but that is a longer timeframe project. We need to work through the details very carefully. Two auto electricians have told us the small fame alt is too light for external regulation, due to heat dissipation. The available space is minimal for swapping out the alternator, so our preference is to modify the existing one. Our existing Balmar smart charger (not currently used, from the old engine set up) has a heat probe for the alt, so we believe we can set safe limits and also de-rate the alt so that it is not running right on the edge of tolerances.

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Sorry about all the drama you are having Fish.
I will ansewer the care for FLA question first.
The advantage of FLA is that they do take a fair amount of abuse and come back hitting. The killer for them is discharging too far for too long and letting the Plates dry out. FLA will take a high charge current, of which you don't come near, so rule out too high a current issue. If kept at a float charge for long periods, they suffer from statafication. This is where the heavier Acid settles to the bottom of the cell and the water floats on top. thus only part of the plate is working properly. An equalisation charge causes bubbling which stirs that electrolyte up and mixes it all again. Equalisation charges need to be done on ce a month when in long term float. Strataphication will not harm the battery though.
If you had a charging issue, I would expect to see damage to both batteries, not just one. I think the issue of one being down on capacity is possible damage from dry plates in that battery. Level checks need to be done monthly and Especially after any equlisation charge.
By the way, a clear sign over ver charging is the top of the battery is always wet around each cap.

I am now very scepticle of these new fandangled load test devices everyone is using. I have just recently been involved with a Car electrics issue. I kept saying, sounds like a battery fault. Car was bought in Auckland and being driven down here. An Auckland Car sparky said ALT and replaced it. Of course, it happened to be really expensive. Fault remained. When it came down here, I said sounds like battery. AA tested battery, charged battery, tested battery, flatten battery, had it for a week. Came back with screeds of paper saying Battery 100% OK. Fault still occured. Looked at Key system, Computer system, relay system and nothing could be faulted. Took to another Car sparky and they called back in a couple of hrs with the result being, BATTERY. They replaced it and the owner has never had a problem since....so far.

By the way, apart from ensuring the batteries remian topped up both with water and with charge, you are doing nothing else wrong.
6 months Warranty?? come on manufacturer. In fact I would be steering clear of any deep cycle battery that has only a 6 month warranty. It means it is not fit for purpose.

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Black dust stuff is usually a sign of belt slipping. Ensure the belt is in good condition and tight. They have a limited life, so replace when needed. Some do so once per year, but I don't. As they wear, they slacken off, so check monthly that proper tension is maintained. 
It is the sides of the belt that drives the pulley, not the base part of it. So ensure that the belt is sitting in the Pulley correctly. If it has worn and dropped into the Pulley too far, it will slip. A slipping belt usually is seen as the sides being shiney and curved instead of flat surfaces. Alternators of 80A or more should be double belted. This is because they tend to drive at high load for extended periods unlike a Vehicle type ALT, which is loaded for a short period and can get away with a single belt.

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A similar issue, I have 4 x Trojan T105 6 volt batteries, 5 + years old, one is always wet around the caps  ( and only that one) They are serviced regularly, at least once a month in the winter and often more than that. 2 solar panels keep them charged, 1 x 75w probably at least 15 + years old and 1 x 100w at 1 year old all through an Epever 20a mmpt controller. The "wet"battery doesn't show any difference between cells when checked with a hydrometer and is consistent with the "dry top ones?????? any and all suggestions welcome.

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A similar issue, I have 4 x Trojan T105 6 volt batteries, 5 + years old, one is always wet around the caps  ( and only that one) They are serviced regularly, at least once a month in the winter and often more than that. 2 solar panels keep them charged, 1 x 75w probably at least 15 + years old and 1 x 100w at 1 year old all through an Epever 20a mmpt controller. The "wet"battery doesn't show any difference between cells when checked with a hydrometer and is consistent with the "dry top ones?????? any and all suggestions welcome.

Switch the caps around, if possible. Might be a faulty cap....

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I guess I do a vacuum every 10hrs approx, but I'm pulling 100+ A at beggining and often takes 30mins

to get to 30A. Big ask for single belt.

I would put a serpentine belt on but have a dual belt for frig compressor on crank.

A 100a is overloaded for a single belt, but not uncommon.

How does it sit in the groove - is it proud of the top? Belts should NEVER touch the bottom of the groove. If you have not done so, you might try a toothed V belt - the good ones are rated a little higher... (Topcog, or Gates Green Stripe)...

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With multiple 6V cells, I seem to remember being told to rotate them round the system from time to time.  May be an old wives tale but seemed to make sense at the time.

 

I went to Lithium about 18 months ago, definitely a less stressful environment.

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With a properly connected bank there is no reason to rotate batts. The key is that the pos needs to come from one corner of the bank, and the neg from the opposite. This forces all batts in the bank to be used equally. Its common to see the connections to the closest terminals used as it easier, or cheaper for shorter cables. Many production boats are wired like this, and a simple change can really extend your batt life.

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Silly question:

I understand stratification of the cell acid from keeping on float for a long time (thanks wheels), and therefore the need to do an equalisation charge to stir up the cells.

 

The question is, would going for a descent sail and gently rocking the batteries (in wave action etc) be enough to stir the acid back up and not need the actual equalisation charge?

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It would have to be a violent movement...

The real answer is not to use wet cells. Gelled VRSLA or AGMs dont have this issue.

 

Acid Stratification Prevention

Acid stratification can occur in conventional flooded cells. During charge, acid is released at the plate surfaces. During discharge, acid is consumed at the plate surfaces. Since the concentration is not uniform, diffusion (spontaneous mixing by random molecular motions) begins. If this mixing occurred rapidly, stratification would not occur, but it is relatively slow, allowing lighter parts of electrolyte to “float” toward the surface and heavier parts to “sink” toward the bottom. The top portion of the plates do not perform as well in contact with lower concentration electrolyte. The bottom portion of the plates do not perform as well with the higher concentration and will corrode prematurely. High voltage “equalization” charging is sometimes used in flooded batteries to make gas bubbles that remix the electrolyte. Immobilized gel or separator-absorbed electrolyte will not“float” or“sink” within itself when a non-uniform concentration exists so it cannot stratify. Therefore, no high-voltage equalizing charge is necessary. Simply recharge at the recommended recharge settings. This means longer life and consistent performance.

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