8 x 200ah batteries die after 18 months

[Hurricane]

I know I've read of physical failures recently, have just done some brief searching and failed to turn up much though. It's possible it was on the cruisers forum, but I genuinely thought it was on YBW, my memory is perhaps not what it used to be.

Output loss via shading is something that any boating application is likely to suffer from I guess, but plenty of people use them successfully despite the inevitable losses.

You are not mistaken.
I also found some evidence that there were failures of semi flexible panels after a couple of years.
That initially put me off using them and at LIBS I approached that particular stand with the aim of installing rigid panels.
That company sells both and their prices are more on a domestic scale rather than that of most marine "rip of" companies.
So they didn't have a "axe to grind" so to speak.
I was very much "won over" by the salesman, so much so that I think it is worth a try.
In fact, it wasn't the salesman - I also spoke to an engineer who explained the manufacturing process.
They definitely won my confidence.

Lets see - I still have to get the final dimensions and compare the space that I have with the panel brochure/data sheet.

 

[BartW]

I believe it is fairly straight forward.
Just buy an MPPT solar controller, connect the solar panels to the MPPT and the batteries across the output of the MPPT.
There probably needs to be some fuses and isolators in there somewhere.
The Victron MPPT controller at just over £200 has a bluetooth addon so that you can monitor the solar panel performance using a mobile phone.

Had a conversation today with a Victron Guy at Boot Dusseldorf,
he basically sugested to have the voltage as high as possible,
so putting 3 or 4 panels in serie, reason:

the SP start to give power as soon as their voltage is a few volts above system voltage (24V in our cases)
you need to look at peak voltage from the panels, say these are 32V, and you put 3 in series,
in the morning, as soon as their total voltage is around 30V, they will start to give power,
ofcause around midday, when the sun is at its maximum, they give 96V (= max power)

when you put them in parralel, their max voltage is 32V, and they will need much more sunlight before they start to work.

 

[WhiskeyTownRacer]

I've no doubt you'll be taking care over placement and obtaining suitable advice as needed, if you have 10 minutes spare you may find the following quite interesting.

This is for a sailing catamaran application, using panels previously installed on their 'RV'. Conclusion was broadly, parallel for the boat (given the likely shading from boom/rigging etc) and was series on the RV as fewer shading issues, it's nonetheless quite enlightening how dramatic shading can be.

 

[Hurricane]

I've no doubt you'll be taking care over placement and obtaining suitable advice as needed, if you have 10 minutes spare you may find the following quite interesting.

This is for a sailing catamaran application, using panels previously installed on their 'RV'. Conclusion was broadly, parallel for the boat (given the likely shading from boom/rigging etc) and was series on the RV as fewer shading issues, it's nonetheless quite enlightening how dramatic shading can be.

Thanks for posting the video

I'm confused - I thought that the diodes would protect against poor performance of the whole array when panels connected in series and one cell goes down.

I think it shows the danger of wiring panels the way that Bart and his Victron Guy at Boot Dusseldorf said.
If you wire in series, there is a danger of stopping current flow whenever one cell fails to output (shade in this case).

However, it isn't as simple as that.
If we are going to use the Victron controlled, we need at least 5v more than the battery bank before the Victron controller switches on.
The semi flexible panels that I like have a max voltage of 18.7 volts so maybe 2 parallel banks of 2 in series might work.

My gut feeling is that Bart's Victron Guy at Boot Dusseldorf is right - the higher the voltage the sooner the array will start the Vicrton controller up and keep it going for longer.
And the questions that I asked at LIBS led me to believe that one cell in shade only shut down half that panel.
I need to ask a more pointed question - 1 cell down how would that affect the rest of the array.

On another point.
RickP emailed me with another thing to consider.
Maybe the failures that we are hearing reported on Scuttlebut etc are due to the panels getting hotter than the rigid ones.
Maybe the small wires connecting the cells (or the cells themselves) can't cope with high temperatures.
Rigid panels have air flowing under them whereas the semi flexible ones are stuck to a surface where the heat can't escape as easily.
I will be asking some more questions of the panel manufacturers.

 

[vas]

Thanks for posting the video

I'm confused - I thought that the diodes would protect against poor performance of the whole array when panels connected in series and one cell goes down.

I think it shows the danger of wiring panels the way that Bart and his Victron Guy at Boot Dusseldorf said.
If you wire in series, there is a danger of stopping current flow whenever one cell fails to output (shade in this case).

However, it isn't as simple as that.
If we are going to use the Victron controlled, we need at least 5v more than the battery bank before the Victron controller switches on.
The semi flexible panels that I like have a max voltage of 18.7 volts so maybe 2 parallel banks of 2 in series might work.

My gut feeling is that Bart's Victron Guy at Boot Dusseldorf is right - the higher the voltage the sooner the array will start the Vicrton controller up and keep it going for longer.
And the questions that I asked at LIBS led me to believe that one cell in shade only shut down half that panel.
I need to ask a more pointed question - 1 cell down how would that affect the rest of the array.

On another point.
RickP emailed me with another thing to consider.
Maybe the failures that we are hearing reported on Scuttlebut etc are due to the panels getting hotter than the rigid ones.
Maybe the small wires connecting the cells (or the cells themselves) can't cope with high temperatures.
Rigid panels have air flowing under them whereas the semi flexible ones are stuck to a surface where the heat can't escape as easily.
I will be asking some more questions of the panel manufacturers.

Mike

I was alerted on this serial connection problem from the guy who's going to provide the panels and who's involved in MANY installations on yachts and some mobos down here.
Just to give you an idea, my mate with the P45 has two panels 260W each on the aft deck overhang, shaded as he moors his boat with bow looking southwest. Gets some clear sun on the port side in the morning and gets v.little during the day. Installed two more (SMALLER!) on top of the bimini and now he's fine.

I'm planning to connect them in parallel as Mitos is moored pointing SE and there are two yachts (36-39ft) two boats to my stbrd side meaning I'll get some shading from their masts at some point during the day which would ruin serial connection charging.
Good thing is that with hard framed panels it should be fairly straight forward to change the wiring method.

cheers

V.

 

[WhiskeyTownRacer]

I'm confused - I thought that the diodes would protect against poor performance of the whole array when panels connected in series and one cell goes down.

My basic understanding of the issue suggests all panels are not equal. The configuration/number of bypass diodes can have a significant impact on the losses but can also be responsible for not insignificant voltage drops. The Schottky diode which is regularly mentioned as being superior for this application still has voltage losses which could seriously hamper a 12V system if arranged on a per cell basis.

I did some cursory searching but didn't find panel manufacturer info on the their bypass diode set up, whether they are per string or per cell.

Again, based on what bit I've read, it would be surprising in the extreme to find reasonably affordable effective panels that have per cell bypass diodes. (which is kind of what your quoted comment suggests you were expecting)

Decided to leave the last two lines in but did also scroll back to the BenQ offering mentioned earlier in the thread, they do mention their diode setup, being 3 per panel - probably being the best compromise of cost, voltage losses and shading protection. FWIW I expect the comments on heat issues, especially with flexible/semi flexible and lack of air flow are likely to be accurate and this problem only gets worse when shading is involved.

Compromises, as always.

 

[vas]

Decided to leave the last two lines in but did also scroll back to the BenQ offering mentioned earlier in the thread, they do mention their diode setup, being 3 per panel - probably being the best compromise of cost, voltage losses and shading protection.

all the panels I mentioned in this thread, and all the others in the 260-300+ bracket I've looked at have 3 of these Schottky diodes, haven't got a clue how these are organised though (strips along the length of the panel or wider areas across it)
A great compromise it is indeed!

cheers

V.

 

[Hurricane]

Again, based on what bit I've read, it would be surprising in the extreme to find reasonably affordable effective panels that have per cell bypass diodes. (which is kind of what your quoted comment suggests you were expecting)

Thanks for your comments - very helpful regarding the diode voltage drop in relation to the low voltages involved.

And just to clear up my expectations, I was (am) expecting diodes across "strings" of cells and shading/failure of one cell to "shut down" that particular string.
I would expect the strings to be wired in parallel within the panel.
Thats my understanding of the panel.

Incidentally, the guy with the BenQ panels is in the Caribbean at the moment and he has told me by email that his panels are currently producing enough power on his sailing catamaran to recharge his battery bank and provide enough power for his water maker and washing machine.
Here's an extract from his email
So far, we’ve not had a night where the batteries weren’t full at sunset. We had a peak of 400ah generated the other day, but mostly the charge system is shutting down to float mode early on (by midday often). We have been running the water maker when that happens as the solar panels are essentially providing free power then, despite it taking 50amps - they just step up to the load. We’ve done a few loads of laundry on the inverter too.

 

[BartW]

I'm planning to connect them in parallel as Mitos is moored pointing SE and there are two yachts (36-39ft) two boats to my stbrd side meaning I'll get some shading from their masts at some point during the day which would ruin serial connection charging.
Good thing is that with hard framed panels it should be fairly straight forward to change the wiring method.

cheers

V.

Vas you have another "need" than me,
in my case its all about recharging on anker,
I prefere that in the morning when the first sunray's reach the panels, they start charging.
with serial connection this is much sooner than parallel. (and much later in the evenings)
on a Anchorage, shadow from masts is hardly ever a problem

I'm also not concerned about the orientation, as for a Anchorage this can alway's be different,
and my rooftop is nearly flat anyway.

 

[vas]

Thanks for your comments - very helpful regarding the diode voltage drop in relation to the low voltages involved.

And just to clear up my expectations, I was (am) expecting diodes across "strings" of cells and shading/failure of one cell to "shut down" that particular string.
I would expect the strings to be wired in parallel within the panel.
Thats my understanding of the panel.

Incidentally, the guy with the BenQ panels is in the Caribbean at the moment and he has told me by email that his panels are currently producing enough power on his sailing catamaran to recharge his battery bank and provide enough power for his water maker and washing machine.
Here's an extract from his email
So far, we’ve not had a night where the batteries weren’t full at sunset. We had a peak of 400ah generated the other day, but mostly the charge system is shutting down to float mode early on (by midday often). We have been running the water maker when that happens as the solar panels are essentially providing free power then, despite it taking 50amps - they just step up to the load. We’ve done a few loads of laundry on the inverter too.

out of curiosity, how many and what size panels has he got?

V.

 

[Hurricane]

out of curiosity, how many and what size panels has he got?

V.

As I say he has a sailing catamaran.
He has 2x200 watt panels on the top of the davits plus 3x330w BenQ panels on a hard top.

Here is another interesting extract from an email from him - a couple of weeks ago.

I would say that series is pretty much always better - you can do the thought experiment (or read http://www.cruisersforum.com/forums/f14/solar-panels-series-or-parallel-68096.html). I have ended up with 3 strings and thus 3 MPPT boxes just because of voltages and siting (2 x 200w, 2 x 330w and 1 x 330w). The shading issue is interesting - I can shade my panels a bit, and its no problem - but if you shade a small corner between 4 cells, that panel drops to nothing. Rigging/sheets etc are not a huge issue though.

 

[vas]

Vas you have another "need" than me,
in my case its all about recharging on anker,
I prefere that in the morning when the first sunray's reach the panels, they start charging.
with serial connection this is much sooner than parallel. (and much later in the evenings)
on a Anchorage, shadow from masts is hardly ever a problem

I'm also not concerned about the orientation, as for a Anchorage this can alway's be different,
and my rooftop is nearly flat anyway.

Bart,

don't get me wrong, I want the panels for exactly the same reason. But since it's a bit of a faff connecting to shore power at the port, I'm also concerned on keeping the battteries topped up during the summer with my AIS, domotics et al on standby and a fridge running. I'll try both wirings and decide on the way.

As I say he has a sailing catamaran.
He has 2x200 watt panels on the top of the davits plus 3x330w BenQ panels on a hard top.

Here is another interesting extract from an email from him - a couple of weeks ago.

I would say that series is pretty much always better - you can do the thought experiment (or read http://www.cruisersforum.com/forums/f14/solar-panels-series-or-parallel-68096.html). I have ended up with 3 strings and thus 3 MPPT boxes just because of voltages and siting (2 x 200w, 2 x 330w and 1 x 330w). The shading issue is interesting - I can shade my panels a bit, and its no problem - but if you shade a small corner between 4 cells, that panel drops to nothing. Rigging/sheets etc are not a huge issue though.

yeah, that's a lot of sqm of panels, I thought there was a typo!
Curious how he wired the three on the h/t, did he go the two on the side together and the mid one alone (as that's the one more susceptible to shading from the boom). After investing in all these panels and mppt controllers, I'd expect to have some decent and large capacity batteries as well.

The 2X300W I'm planning to install on a good sunny day in June, I'd expect a 9hour production of an average (maybe too optimistic of 23A) so say 200Ah with panels temp at around 50C.

cheers

V.

 

[Hurricane]

yeah, that's a lot of sqm of panels, I thought there was a typo!
Curious how he wired the three on the h/t, did he go the two on the side together and the mid one alone (as that's the one more susceptible to shading from the boom). After investing in all these panels and mppt controllers, I'd expect to have some decent and large capacity batteries as well.

The 2X300W I'm planning to install on a good sunny day in June, I'd expect a 9hour production of an average (maybe too optimistic of 23A) so say 200Ah with panels temp at around 50C.

cheers

V.

His hard top is over (what we would call) his cockpit - just below the end of his boom.
He recently added the hard top and needed a hatch that he can look through whilst helming.
He sen me a pic but I'd rather not post it without his consent.
This means that he has 2 panels one side of the boom and 1 panel the other (same side as the hatch) - if you know what I mean.
Each side is on its own circuit - 2 panels on one circuit 1 panel on the other circuit - thats how I understand it.
Each circuit is fed into its own MPPT controller.
As said above, there are 2x200w elsewhere and those are also on their own MPPT.
So, thats 3 MPPTs - not all Victron.
But he said that the Victron one(s) seemed to work better than the other(s).

 

[Hurricane]

Update

Just got back from the boat.
It was very clear that the eyebrow roof curve is too much for rigid panels and would look awful.

We did a quick "mock up" of the semi rigid ones to see what it would look like.
We cut some bin liners and stuck them on the eyebrow.
To get 600 watts from the semi flexible ones in the space available, there need to be 4 of them.
To make them fit, the centre ones will be offset longitudinally but that works quite well making them look like roof windows.

So, today, I ordered 4 of these semi flexible ones with adhesive backing.
https://www.photonicuniverse.com/en...th-self-adhesive-backing-made-in-Austria.html

Photonic Universe were very helpful - although not having a specific data sheet, they came back to me with all the technical data.
I'm reasonably confident that these panels will last but time will tell.
A yachtie friend of mine has some similar constructed panels that are 6 years old and still working.
These particular ones have only been available for a couple of years - I suppose has to be the Guinea Pig!!

I also ordered a new set of batteries and will be getting a Victron MPPT controller - probably this one:-
https://www.victronenergy.com/uploa...lueSolar-charge-controller-MPPT-150-35-EN.pdf
And the Bluetooth interface so that I can monitor the panels performance.

Maybe I will start a new thread when I've fitted them.

I have pics of the mock up if anyone is interested.

 

[Bouba]

Update

Just got back from the boat.
It was very clear that the eyebrow roof curve is too much for rigid panels and would look awful.

We did a quick "mock up" of the semi rigid ones to see what it would look like.
We cut some bin liners and stuck them on the eyebrow.
To get 600 watts from the semi flexible ones in the space available, there need to be 4 of them.
To make them fit, the centre ones will be offset longitudinally but that works quite well making them look like roof windows.

So, today, I ordered 4 of these semi flexible ones with adhesive backing.
https://www.photonicuniverse.com/en...th-self-adhesive-backing-made-in-Austria.html

Photonic Universe were very helpful - although not having a specific data sheet, they came back to me with all the technical data.
I'm reasonably confident that these panels will last but time will tell.
A yachtie friend of mine has some similar constructed panels that are 6 years old and still working.
These particular ones have only been available for a couple of years - I suppose has to be the Guinea Pig!!

I also ordered a new set of batteries and will be getting a Victron MPPT controller - probably this one:-
https://www.victronenergy.com/uploa...lueSolar-charge-controller-MPPT-150-35-EN.pdf
And the Bluetooth interface so that I can monitor the panels performance.

Maybe I will start a new thread when I've fitted them.

I have pics of the mock up if anyone is interested.

I for one would be very interested in following your progress. Do the panels bend in both directions?

 

[Hurricane]

I for one would be very interested in following your progress. Do the panels bend in both directions?

OK - I've started a new thread.
Bit unfair on the OP - the subject seems to have changed.

This is a link to the new thread
http://www.ybw.com/forums/showthread.php?472910-Solar-Panels

 

[MedMilo]

Am conscious that I've yet to report back on how this saga ended up!

- We installed 8 of these http://shop.odysseybattery.com/p/pc1800-ft for the domestic bank
- And 4 of these of these http://shop.odysseybattery.com/p/pc2250 for the starter bank
- All the charger cabling was replaced with uniform length cable runs
- The battery box was rebuilt with a stainless steel frame
- A crossover switch fitted to allow the domestics and starter bank to be joined in the event that the starter bank fails (this is standard on many boats but, weirdly, not on Sq 65s!
- An audible low voltage alarm fitted
- A system for sending an SMS to my phone should the shorepower fail was fitted

And I have to say that thus far the new system has proved to have enormous capacity and it's quite a struggle to get the voltage to drop at all, even overnight on the anchor.

I think that the lessons from my pov would be;
- perhaps gels aren't suitable for the less than ideal marine environment in which perfect battery management is hard to achieve (others may well disagree with this!)
- I'm told that AGMs deal much better than gels with the occasional big discharge caused by, say, a dishwasher or 1000w kettle - apparently gels don't like this sort of use (again, others may disagree)
- don't assume that the OEM installation has been done correctly in terms of uniform cable runs etc, mine wasn't!
- shore power sometimes trips out which, if left for a few days, can damage batteries irreversibly so it feels like an easy win to fit one of these https://www.amazon.co.uk/iSocket-HomeGuard-Protection-Listening-Thermostat/dp/B00CALOXLY and they work brilliantly

I should point out that BUK completed all of this work to an incredibly high standard under warranty, nearly two years after I'd purchased the boat, despite the fact that they had no chance of recovering a penny from the 'old' Fairline. Simply remarkable service in every way. So I guess my final lesson might be to, if at all possible, only deal with an excellent dealer like BUK!

 

[TwoHooter]

Congratulations on choosing a good supplier for your boat!

I used the link to look at your new house batteries - the Odyssey PC1800-FT - I am probably being dim but I can't see what chemistry they use. Your last post said 'perhaps gels aren't suitable for the less than ideal marine environment' and seems to suggest they are AGM - are they indeed lead AGM? Or are they one of the Lithium variants?

 

[MedMilo]

Congratulations on choosing a good supplier for your boat!

I used the link to look at your new house batteries - the Odyssey PC1800-FT - I am probably being dim but I can't see what chemistry they use. Your last post said 'perhaps gels aren't suitable for the less than ideal marine environment' and seems to suggest they are AGM - are they indeed lead AGM? Or are they one of the Lithium variants?

They're lead AGM but apparently use some clever engineering to get the most effective plate configuration - so far they seem to have incredible capacity (although they are, of course, new so perhaps this is to be expected!). Since I had the issue last season with the previous gel installation, a few people have said to me that they'd swerve gels and that AGMs are more forgiving in a marine situation where partial generator charging and occasional surge discharging are a reality of life.