Battery Issues - A Quandry

[BroadAmbition]

 

Forumites - those with electrical knowledge / experience, maybe you can help with this one:-

Ok here's the thing.  'B.A' has five 110 amp leisure batteries fitted in two banks, one with three and one with two.  Over my recent week solo afloat after only 3- 4 hours of engine shutdown the onboard inverter stared beeping alerting me to low battery power.  On checking our power management display voltage was down to less than 12v - 10:5v to be precise.  Firing up the beta thereby getting both alternators going soon rectified the situation but it shouldn't happen after that amount of time, especially all the inverter was supplying was the tv and maybe a phone charger.  So a bit of detective work and eliminating some scenarios was called for. I switched the main isolator over to draw power from battery bank 1, the display panel now showed 9:5v - there's the answer I thought, there is a dud battery in bank 1 dragging down the rest of them, switched over to bank 2 = 10:5v showing on the display. Next day both banks on-line and being charged, when I stopped cruising thereby switching off the beta and alternators, I switched to draw power from bank 2 only, confident that three 110amp fully charged batteries would last me the evening - Nope same thing, low power after 3-4 hours down to 10:5v yet again.

Following so far?  I'm now think that there is a dud battery in both banks.  So called in at LBBy, borrowed their drop tester, disconnected every battery and used the drop tester, making sure it was working and producing heat on a proper load test.  All five batteries passed the test with flying colours.  So I'm stumped.  the batteries were last renewed and fitted Dec 11 so they are over 4 x years old.  Bro' Howard will accompany me on a future visit and we will check out the entire electrical system to see if we can find something that is causing the issue

In the meantime, your thoughts / experience would be welcome.  Thanks,

Griff

[Guest]

As you've now tested each individual cell in each battery, I'd say that's quite conclusive Griff.

Such a high voltage drop with healthy, charged 12v banks must now be either a connection or the battery management monitor itself.

Have you tried directly checking the battery voltages with a separate multimeter when the inverter and/or management meter shows low voltage ?

Maybe also try unbolting all of the high amperage crimp eyes, re-greasing them, and bolting them back on. (Negatives as well).

[ranworthbreeze]

Hi Griff,

When you did the drop testing on each battery what was the battery voltage? Did you test the electrolyte? What is your voltage with the inverter off?

At four years you are on borrowed time with any batteries, as you know we are out for many weeks and we are lucky if our batteries last two years.

Regards

Alan

[grendel]

my thoughts are that you are not getting the charge into the batteries, when charged each battery should be at about 12.7 volts.

so my suspicions would be either the alternators or the charge management system. what does the drop test involve? I used to have an old fashioned tester, basically a couple of cattle prods with a huge resistance bar with a voltmeter. shorting this across the battery put a very heavy load on it, while measuring the voltage, thus giving the battery a good workout under load, if the voltage dropped quickly, the battery was iffy.

if the batterys are good and the charging system is good, then you must have a higher load than you are expecting, remember an inverter if it is on is always drawing power, and the other thing that may have heavy usage is the fridge, so check the connections for those.

Really its just a case of working through the system one item at a time, eliminating them from the equation.

[grendel]

http://www.mmbalmainauto.com.au/PDF/State_of_charge_12_volt_batteries.pdf

here is a good chart showing charge to voltage, at 12.2 volts you are only at 50% capacity, which is really as low as you want to be, I wonder if its possible to spend some time individually charging each battery back up to full capacity from shore power at some stage, you do have to do all of them before reconnecting them back to each other, as one low charged battery will drag the others connected to it down to its level.

[diesel falcon]

At 4 years  old, and well used i think you,ll have to bite the bullet and have a whip around all the owners and buy new, hard i know for someone from gods county ? hay ho, a bill split 4or 5 ways won,t be toooo bad.

Temperature can play a big part in old batteries, you may find you can get another season out of them but my domestic battery only lasts max 2 seasons, then shows all of the symptoms you discribe, an amp meter will answer what load is on them....good luck! (with the collection!)

[MBA Marine]

You may have a function on the boat not working and incorrectly fused so it does not blow/trip out, for example a bilge pump that has failed but still getting the call to operate from its switch, if a function has failed and creating a short then you will get a rapid power drop. In an ideal world this couldn't happen as the correct size cable and appropriate fusing would always be used, sadly this ain't a perfect word and I have found many an example of bad practice and not always DIY.

[Guest]

12 minutes ago, MBA Marine said:

In an ideal world this couldn't happen as the correct size cable and appropriate fusing would always be used, sadly this ain't a perfect word and I have found many an example of bad practice and not always DIY.

I'd be very surprised if BA had any "bad practice" wiring in it !

[MBA Marine]

1 minute ago, Strowager said:

I'd be very surprised if BA had any "bad practice" wiring in it !

Sadly I would not, people take their boats to yards thinking that yards know what they're doing, most do, some that don't know seek advice and some work on a 'well it works and thats how I have always done it' practice.  For example I re-wired the domestics on a boat and as I was removing the old I found a scratty bit of 1mm running down the boat providing power to a number of pumps water and drainage, then I look to the recently installed leccy toilet and find it powered via a choccy block cut in this same 1mm, look to the fuse to find it uprated to 30a to cope with the loo!!!  worst of all distance from distribution to loo was about 3m and an easy run, the owner was not a DIYer and informed me where the loo had been fitted. even the best boats can have a nasty behind the scenes.  

[Oddfellow]

Drop testers are NOT ideal for leisure batteries. In fact, there is no simple way to test them quickly.

A drop tester puts a massive load on a battery to see how it deals with it. In a deep cycle leisure battery, the make-up is designed for slow discharging and recharging. Fast discharging and recharging can warp the plates (as they get hot) and shorten the life of the battery (but at four years. they're doing well anyway). 

The ONLY way to do this properly is to fully test each cells electrolyte when the battery is fully charged, making note of any variation. Then, put on a known load and measure the discharge over time, plotting the battery's life span. Yep, that's about it. There may be very expensive tools around to do this, but I don't know anyone that has one. We all use drop testers and hydrometers in the boat yards (someone correct me if I am wrong). 

I have spoken with a technical guy at a company that produces micro-processor controlled battery test gear where the testers are £200 or so. He told me that whilst his testers are very good at simulating a full discharge test in moments, the results given are meaningless without a benchmark to test against. This gets more useless as a report when you realise that you would have to benchmark every batch of batteries you received and know which batch the battery was from so you could check the status of any given battery. This MIGHT work for a hire yard that could potentially log all the batteries in use, but would be pretty useless in this situation. 

So, back to testing each battery separately with a timed drop test as described above. 

Poor connections, corroded terminals, failing diodes, slipping alternator belts, under-sized cables, unknown loads and so on are all possibilities; but given that you have four year old batteries, perhaps they have simply had their time. 

Also, like Mark says above, there are some terrible wiring horrors on boats. Because it's only 12v, people think it's easy and safe - it is neither but there are plenty examples of dangerous wiring around. We see all sorts. 

For the record, I am BMET qualified, so not only have experience with boat electrics, but also a bit of paper that says I know the rules. Don't confuse BMET with the Boat Safety Scheme - they are very different things. The BSS makes a mockery of some of the proper rules and over-eggs other regulations unnecessarily - it's as though it were contrived by a bunch of paper-pushers that simply cherry-picked ideas from different standards and added their own twists, just to be different. 

 

 

[Regulo]

Sounds like you have at least one bad battery in each bank. After fully charging, you should disconnect EACH battery individually, wait for 30 minutes, then check the SG of each cell of each battery. The problem will then be obvious. If the situation has been ongoing for some time, you might have to renew all your batteries. Sorry!

[Guest]

1 hour ago, MBA Marine said:

Sadly I would not, people take their boats to yards thinking that yards know what they're doing, most do, some that don't know seek advice and some work on a 'well it works and thats how I have always done it' practice.  For example I re-wired the domestics on a boat and as I was removing the old I found a scratty bit of 1mm running down the boat providing power to a number of pumps water and drainage, then I look to the recently installed leccy toilet and find it powered via a choccy block cut in this same 1mm, look to the fuse to find it uprated to 30a to cope with the loo!!!  worst of all distance from distribution to loo was about 3m and an easy run, the owner was not a DIYer and informed me where the loo had been fitted. even the best boats can have a nasty behind the scenes.  

I quite agree with that in perhaps the majority of cases Mark, as you say, many DIY'ers and many "Professional" yards can make appalling mistakes..

However, I still doubt whether BA has any "scatty" bits of anything, least of all in something as crucial as electrical cabling. Judging by Griff's posts over the years, the complete rebuild and subsequent maintenance has always sounded pretty good to me......

[BroadScot]

I would agree with Strowie, with 50 plus years of electrical knowledge, and pics I have seen of BA with lecky work shown, be they still pics or video Robin has taken, has all looked very tidy and proper to me.

Batteries four years old sends alarm bell warnings to my wallet ! Sorry Griff, best stick a few more tiles on to pay for a new set of batteries. I would however, be delighted to be proved wrong!

Iain

Edited March 13, 2016 by BroadScot
Spelling!

[BroadAmbition]

Blimey - logged in this morning just now to find loads of help / suggestions - TVM proper grateful.  I'll have to get Bro to view this thread (He's out at the moment spoiling a good walk - Gentlemen Only Ladies Forbidden).  Both of us know about 12 and 240v electrics me to a limited degree but Howard is a pro, qualified so he will be able to respond better than I can.

In the meantime some points that I know and can respond to.

Stowager - No I haven't checked with voltage meter when they are reading low but will do so.  All connections are good, I had a cursory check round and could find none suspect, a more in depth check required, the battery management panel draws very little power and all it really does is provide information, I can assume it is working correctly as the alarm on the inverter backs up what it is displaying.

Ranworthbreeze - the voltage was around 13v, everything was off including the inverter as I had disconnected all batteries at the same time, cannot check electrolyte levels and the buggers are sealed units. Yes four years we are on borrowed time but can't see all of em failing at once.  The first set was purchased / installed in 07, we are now on the second set.  Extreme temperatures in the engine compartment where the batteries are installed is rare, we have tube heaters for the winter that come on when the ambient temperature drops down to +2deg and she is always plugged into shore power when at home berth so the 240v charger can keep the batteries topped up

Grendel  -  I'm confident that both alternators are providing the charge ok, the management display panel tells me so when the Beta is fired up.  The drop tester I used in principle is the same as yours, it has a display and heavy bare heating elements in it to give them a proper load, plenty of heat produced on each test.  Working through the system - Agree

Diesel falcon  -  If we have to go for a new set of five, then I'll be tempted to go for those Rolls Gell batteries, but they are getting on for around £200 each, then the outputs of the alternators has to be adjusted as well

MBA Marine - All fused / wired correctly, I checked all fuses - More on the below

 

Freedom Boating  -  Thanks for your advice, I read it all then read it again to make sure I had got it, I have and agree with what you say.   I had to use what was available at the time, there is more I can do on my next visit and will do so.  Testing the electrolyte is out what with them being sealed units, however we may be able to force open them up to have a proper check - I hope so

Regulo - Yep the SG is the issue here

BroadScot - It could well be it is open wallet time

 

All  -  In an ideal world with money no object I'm kinda hoping that the batteries need re-newing and that the inverter is tired.  This would give me an excuse (As if ever I needed one) to upgrade the inverter to a 3kw unit (It's on our wish list), replace all five batteries with the Gell type (Then there is the high cranking starting battery as well), fit two new flat bendy type solar panels.  But my work is more practical and we have to be sensible here, there are other expensive items on our wish list that are coming to the top of the list as well

Wiring  connections /. electrical system in general  -  To put some minds at rest here, when we restored 'B.A' we stripped out every last inch of cable EVERYWHERE, every electrical fitting - the lot and started again with a blank canvass.  The whole system was installed by me and Bro' using new and going over the top, never settling for 'Make Do' or  'That'll be good enough' we went the extra mile and then some. this includes both the 12v and 240v systems.  Everything is fuse protected at the correct rate, sometimes slightly under fused just to be safe.  All connections are either crimped or soldered, in most cases both, we really did a professional job, and anyone of you are welcome to have a look-see.  What I'm saying here is that I'm confident the installation of the electrical system is second to none.  That is not to say something could not have come loose etc - it happens but we really did guard against developing any faults through bad installation / practise.

Having said that, - something is amiss!  I will of course keep you updated on how I / We get on and very much appreciate your advice.  Thanks,

Griff

 

 

[BroadScot]

14 minutes ago, BroadAmbition said:

I'll have to get Bro to view this thread (He's out at the moment spoiling a good walk - Gentlemen Only Ladies Forbidden).  

Nothing wrong with Gowf!  Especially IF you win the sweep money!

Iain

[ZimbiIV]

Griff, agree with you four year old batteries is pushing it, when I had a battery problem it was the inverter, even when switched off it was taking current? I disconnected it completely gave the boat a good long run batteries were fine.

Don't bother with an inverter now.

paul

[Vaughan]

Sorry to come late (yet again) to this thread. I agree with all of you, especially Freedom, but there are two main points not discussed (in my opinion).

1/.

If your batteries are going down to 10.5 or even 9.5 volts then that is unacceptable in any circumstances, not only for the batteries themselves. At that level of volt drop you are going to burn out some appliances on the boat, such as fluorescent light fittings, to say nothing of your charge management (splitting) system itself, and maybe the inverter. In the ideal world your batteries should not get below 12 volts at any time, and a starter battery must be fully charged at all times.

2/. 

This is all a question of deep cycles. The number of cycles your battery will accept is quoted by the makers. A normal lead/acid domestic battery will accept 400 to 600 cycles. If you spend the night on your boat, that is one cycle. So how many nights have been spent, over the last 4 years? I have a feeling this is just a matter of "anno domini"! Hire fleets cannot expect their batteries to last more than 3 years, at the most, if they are the "normal" type.

 

There are batteries called Elecsol, which will accept around 1200 cycles. They are expensive, and must be kept topped up with distilled water regularly. They also have a strange ability to "re-charge themselves" over a few hours.

If not, the Optima batteries are excellent, and maintenance free. The yellow one is the domestic version.

 

 

[Oddfellow]

Griff, 

For the record, soldering terminals on a boat is contrary to BMET regulations. Solder joints are liable to fracture through constant vibration. Fractures lead to arcing. Arcing leads to heat build up. Excessive heat leads to insulation break-down and this can lead to fires. 

Use Crimp terminals only. If you are using choccy blocks anywhere, only use those with tangs gripping the cables; never those that screw directly down to the cable (as it causes a major stress on the copper and can easily fracture).

 

Andy

 

 

[BroadAmbition]

Hi Andy,

The 'tinned' ends to my knowledge are only some large crimped fittings within the engine bay where they can be easily seen / inspected.     There is only ONE choccy connection onboard to my knowledge and that is a temporary affair when I recently changed the fresh water pump, it will be replaced next visit.  All cables fitted are of the multi-strand variety to reduce breakages with vibration etc. As part of a major engine service it is standard practise onboard to check as many connections / wiring as we can get to.  The 240v system is a true ring main with seven double sockets fitted

Talking with Bro' last night, we are agreeing that we are on borrowed time with the age of the batteries onboard and will probably bit the bullet and purchase five new lead acid leisure items. Howard is not that keen on the Gel type, what with having to adjust the alternators plus the smart charging boxes onboard to cope with them

Griff

[BroadAmbition]

Elecsol batteries are no longer available it seems, there is a replacement that is claimed to better:- Enduroline Calcium Leisure Battery, they come with a 4 x year guarantee.    Some more research required, especially on the price

Griff

[ranworthbreeze]

Hi Griff, 

I had a look on Ebay and the prices there seemed to be around the average price for a boats battery, the advert I was looking at from  Tayna-Batteries included free delivery.

Regards

Alan

[dnks34]

Some of you may not agree but I always buy the cheapest 110ah lead acid leisure batteries I can get hold of at the time I need a replacement. 

Our last lot of cheapo batteries lasted us just over 4 years and funnily enough all failed more or less together.   At around £265 for the 5 (if you shop around to get a good deal) I didn't think 4 years was to bad really.  

I would obviously love them to last 8 years but batteries being batteries I am not prepared to find out how long a higher priced / quality one would last!

If I spent 20 - 30 extra per battery would I be any better off in the longterm, the budget ones performed well for us that is till they started failing! 

 

[kfurbank]

Having had some bad experience with Multicell batteries I would avoid them at all costs. I believe a number of the hire yards use them because they are local and cheap, but it could also explain why so many hire boats run engines at moorings. I have had two batteries from Multicell which after a year or so develop a rather strange fault similar to what Griff is seeing. Basically one cell in the battery develops a very low capacity to hold charge.

When they go faulty they will very quickly drop to 10.5V however it would appear only one cell is low on charge with the other 5 fully charged. When you charge the battery using a four stage charger the battery very quickly goes through the boost phase with the terminal voltage rising very quickly. Even with the maximum time set for the absorption phase they seem to stop taking a charge very quickly. Once the charger returns to the float phase the battery should be fully charged, and indeed the terminal voltage will show 12.6 or 12.7V. However put a decent load on them and within a matter of minutes the battery will drop to 10.5V. I have seen a faulty battery go through the boast phase in 15-20 mins, whereas a depleted good battery will take 3-4 hours. Likewise with my discharge test a 100W load will flatten the faulty battery in minutes rather than hours. 

Normally when a battery reads 10.5V it is a sign of a shorted cell. With these batteries it is almost as if 5 cells are able to accept 100% charge with the faulty cell accepting a maximum of 5 or 10% charge. I had quite a battle with Multicell to accept that the batteries had this fault. If you take the battery to them fully charged, they do a drop test and it passes. You need to get them to do a full capacity test to show the fault.

If one of these batteries is installed in a bank in parallel it is even more difficult to diagnose as effectively the good battery masks the problem. Where you might expect to have 2 providing 220ah you end up with something like 120ah. Problems really occur when you run heavy loads because then the one good battery gets twice the punishment.

I was fortunate to be using these batteries in series to provide 24V. At least when one battery develops a fault the overall voltage drops to 23.1V indicating a fault and causing the invertor to alarm, but the good battery is protected from discharging into the faulty one. It is also easier to diagnose the faulty battery without disconnecting any wiring, as you can still meter each battery separately, something it is not possible to do when they are in parallel.

My first set of Bosch leisure batteries lasted 6 to 7 years, indeed 2 of them are still going strong 10 years later. Needless to say last year when I needed to replace the Multicells that barely lasted 3 years, I went back to Bosch. They are not cheap but are really well built.

 

[LondonRascal]

At the end of the day you can spend a great deal on batteries and, while with some makes there is a physical difference in construction - the amount and quality of the lead for example and low self discharge rates over all it is not always the case that when looking into batteries the 'send cheapest' might be any better than the most cheap - but is likely to be not as good as the most expensive.

I've emailed Charlie and Howard privately - but form my own experience (and I have had a fare share) of battery issues on hire boats I knew something was not quite so happy over new year when Shiela and I were on the boat.  However, I think the issue began earlier still in October during Lads Week when, the low voltage alarm came on and it was 'diagnosed' as being a slow cooker that had been on - but I was not 100% sure that would cause an issue since we had also had a good run that day too.

When I was on the boat I did not get a low voltage alarm, but did notice that the batteries were not being that happy voltage wise but also when charging the amps being fed into them seemed on the lower side. 

Fact is the batteries are going to be weak by the very issue of the amount of cycles they have been through in the period of time they have been fitted, not to mention some recent discharge hat have taken them down in 'damaging' levels of discharge but I would not just rush into buying 5 new batteries, installing them and thinking that is that.  I suspect there may be an underlying issue, perhaps a drain on them (I had thought i may have been caused by an always on mains transformer for an overhead light) but this was isolated last maintenance trip - there really is not a great deal of stuff on Broad Ambition that would use many amps anyway, all lighting is LED, things like the water pump, bilge pump do not cut in too much so the highest drain is the fridge but that again is not on all of the time.

It may be the inverter has an internal issue that is soaking up amps even in standby, it could be the diode in the solar panel has gone loopy and once darkness comes the panel actively takes power out of the batteries could it be the smart charger system that is not all happy, a wiring issue o loose connection - you see it could be any number of things or a combination over and above weak batteries.

If I was headed out to buy batteries I would not shop local, there are so many places online with free next day delivery all wanting business.  I have heard good things about VARTA batteries too (in their professional range) and they are good value - a 'bog standard' Lead Acid battery might be got for about £70.00 to £80.00, with a better known brand peeking into the £100.00 to £120.00 range but these are for 105ah to 110ah capacities - VARTA do a 140ah battery (not fancy AGM) for £150.00 delivered with a 4 year guarantee. Problem is the battery is a different size to most so the battery boxes would not accommodate them.

Just for reference though with real world experience - when my dad bought his Mercedes it had a Yuasa battery fitted.  The car was an 05 plate and the battery had a scribble that it had been fitted in 2005. It failed in the winter of 2014 'just like that' - it was replaced with a NUMAX battery.   By the time the car was written off if you left the car un-driven for about 4 days you knew it would need a booster to start.  I know nothing about either brand but it goes to show how variable things can be.

 

[grendel]

Yuasa batteries are what the professionals use for burglar alarms and (in the case of the company I worked for) emergency switchgear tripping, these batteries had to withstand constant trickle charging and when we installed them had to have a 5 year guaranteed life, I am still using some that I got in 2008, when a whole box was discarded because they no longer had a 5 year warranty left on them, I guess they were 3 years old at least when I got them. the only problem is that these are 6V 10Ah.

Grendel