DIY LiFePo4 installation - Don't do what I did (maybe) . . .

[Tradewinds]

MGN 550 (M+F) Amendment 1: Electrical installations - guidance for safe design, installation and operation of lithium-ion batteries

MCA have recently issued guidance on how to safely install Lithium batteries - I would assume that the insurers may accept compliance with this.

Having very quickly scanned the document. IMO, 99.99999% of yacht installations probably won't comply.

 

[st599]

Having very quickly scanned the document. IMO, 99.99999% of yacht installations probably won't comply.

Better than their new plotter docs, which 100% won't and can't comply with.

 

[Neeves]

[Quote

The director who responded at Pants wrote the following - which was quite explicit

(my underline)

I understand you have been in correspondence with Pants & seem to have a lesser, all encompassing, response. I have read many of your posts on the Cruisers Forum and you seem to be extremely methodical in your approach but judging by your questions you posted you are far from 'professional' more a very diligent amateur (as I thought I was). Note: No insult intended.

Although the response to me from Pants was a big setback, I too found the whole exercise interesting and I learnt a lot. If I had intended to set off again on a big adventure I might have been more keen to a) fight my corner or b) pay for the appropriate professional expertise - but my long-distance cruising days are over so, for a quiet life, I decided to stick with LA. I'll keep my newly built LiFePo4 battery bank at home just in case the lights go out . . .

No need to wait for your lights to go out.

I built a Lithium battery bank suitable to Abe transferred to a yacht, as is, and have run a power cable to the house from the inverter. We use the power to run appliance in the kitchen, air fryer, bread maker etc. It has noticeably reduced our power bills.

The criticism I received for building a land based marine system was extraordinary.

Jonathan

 

[Dockhead]

[Quote

. . . . I have read many of your posts on the Cruisers Forum and you seem to be extremely methodical in your approach but judging by your questions you posted you are far from 'professional' more a very diligent amateur (as I thought I was). Note: No insult intended. . . .

No insult taken. I would certainly agree that I am no professional. Which is why I have carefully sought guidance every step of the way by more knowledgeable people, and why I will seek professional help confirming the finalized design.

I am hoping not to have trouble with the insurers. We shall see. I'll post about my experiences when I'm finished, in case it will help others.

 

[Sea Change]

Having very quickly scanned the document. IMO, 99.99999% of yacht installations probably won't comply.

I'm not sure it's possible to comply. I'm not aware of any BMS design that works with a power source other than the battery itself, yet that is one of the requirements.

 

[Tradewinds]

I'm not sure it's possible to comply. I'm not aware of any BMS design that works with a power source other than the battery itself, yet that is one of the requirements.

Maybe Nigel Calder has a cunning plan . . .

 

[Dockhead]

I'm not sure it's possible to comply. I'm not aware of any BMS design that works with a power source other than the battery itself, yet that is one of the requirements.

I don't read it that any BMS at all is required unless battery is used for propulsion.

"All vessels which use batteries as a source of power for propulsion should have an approved Battery Management System . . . "

What concerns the certification of cells as hazardous goods -- that is only a recommendation.

Most of the text seems to be concerned with batteries used for propulsion. I'm not sure how much of it applies to batteries used for electrical power supply.

No account seems to be taken of the differences between LiFePo4 and other types of lithium ion batteries.

Not sure how useful this guidance is for our cases.

 

[jwilson]

The MCA have recently published requirements if a coded (ie charter or commercial) boat is to have "lithium batteries". The requirements are such that I doubt anyone is going to fit them in such a boat unless the whole boat is purpose-built to have them - possibly as an fully electric-powered boat, though the one very expensive such new yacht I know of will not comply. Ventilated steel battery boxes with their own fire suppression system. No distinction between "safe" types of batteries and the unsafe types. Last year I contemplated replacing three paralled lead-acids with one bigger LiP0 in a coded boat - glad I just bought three new LAs.

 

[Sea Change]

I don't read it that any BMS at all is required unless battery is used for propulsion.

"All vessels which use batteries as a source of power for propulsion should have an approved Battery Management System . . . "

What concerns the certification of cells as hazardous goods -- that is only a recommendation.

Most of the text seems to be concerned with batteries used for propulsion. I'm not sure how much of it applies to batteries used for electrical power supply.

No account seems to be taken of the differences between LiFePo4 and other types of lithium ion batteries.

Not sure how useful this guidance is for our cases.

I admit that I've only skimmed it, but section 2.12 says "The BMS should have appropriate alternative power".
Is there a preceding clause which means that this applies only to propulsion?

 

[Beneteau381]

Pantaneous - but it might be Australian specific, how would I know? I actually thought there was a similar restriction on rigging life in the UK.

With Pants we needed a survey, not an issue. Within a couple of years they changed their underwriters and wanted a new survey, the old one was not accepted. We had a new survey, same surveyor so cheaper - but still a cost (completely daft). I was annoyed. We were then advised that unless they received confirmation of replacement rigging we would be covered but not for loss of rig or any incidental damage caused by the rig loss. They also became restrictive with sailing overnight (and you cannot cross Bass Strait without part of the passage being 'overnight') - requiring at least one other person. I could pick up a back packer, never sailed before, that would meet requirement - completely daft. Normally we sail as a cruising couple - no issue - but domestic demands can alter that arrangement.

Jonathan

You know what thought did!

 

[Beneteau381]

Starlink Mini is about 25w, so 25*36=900wh, which is a little under what the unit claims (1152wh).

But it's just arithmetic really. Look at what you need to run and get the battery or power station that can do that.
Your Bluetti is roughly equivalent to 190Ah of lead acid, but it's far more useful because it can charge and discharge faster, and has all the extras (charger, inverter) incorporated. Certainly a solution for some situations.

Indeed. My mate went through a scoping exercise and the ancillaries such as charger invertor cost put him off

 

[Neeves]

You know what thought did!

As usual you provide words of wisdom, nothing good ever came from people thinking .... so let other people do the thinking - totally unnecessary for us.

Jonathan

 

[Neeves]

First of all, it won't "void your insurance". Typically they will exclude coverage for battery fires, if they object.

My plan is to prepare very detailed design documents including calculations. And try to get an EE to write an opinion that the design is sound. This is not just for insurance, but simply good practice. You don't want to make a mistake here.

I will attempt to find an electrician who will inspect the completed system and give a written opinion that the installation has been carried out according to the design and with good practice.

Perhaps I'll even hire such to do the final assembly, particularly of the cabling.

Whether all this is worth it or not depends on how you value your time. I've already spent hundreds of hours designing my system. I justify it with the enjoyment I am getting out of it -- it's fun, and also great to have a really deep understanding of how the system works. Can't justify it economically, if your time is worth anything.

You could simply post here and get an assessment of your plans and ideas. Paul is a practising, professional Electrical I am sure he will have views that might reflect some in the industry.

Jonathan

 

[Sea Change]

Indeed. My mate went through a scoping exercise and the ancillaries such as charger invertor cost put him off

It depends on what you're using it for.
If building a new system from scratch there can be almost no upfront penalty for choosing LFP, and given the far longer service life, a substantial long term saving.

But just because something is a no brainer for a full time liveaboard doesn't mean it's the right answer for somebody who uses their boat a few weekends of the year.

 

[Dockhead]

You could simply post here and get an assessment of your plans and ideas. Paul is a practising, professional Electrical I am sure he will have views that might reflect some in the industry.

Jonathan

Thanks. I'll finish writing up the design and post it for sure. It might give others some useful ideas, too. There will be a manual, too.

I have consulted with real EE's every step of the way, and have used AI's. I've learned a ton in the process, which has been fun.

The acid test, however, will be if I can get a real, reputable EE to give a written appraisal of the design which I can use with my insurance.

 

[Dockhead]

I admit that I've only skimmed it, but section 2.12 says "The BMS should have appropriate alternative power".
Is there a preceding clause which means that this applies only to propulsion?

Section 4 starts by specifying that BMS's are required for batteries used for propulsion.

That may or may not mean that requirements for BMS's apply to BMS's which are not required.

You might be right; I don't think it's quite clear.

In any case, this requirement is not fulfilled and possibly can't be fulfilled for BMS's available for our power systems.

 

[PaulRainbow]

MGN550 is totally irrelevant to us. It's a guidance paper for Lithium-Ion batteries.

Hands up everyone that has Lithium-Ion batteries on their boat.

 

[PaulRainbow]

No need to wait for your lights to go out.

I built a Lithium battery bank suitable to Abe transferred to a yacht, as is, and have run a power cable to the house from the inverter. We use the power to run appliance in the kitchen, air fryer, bread maker etc. It has noticeably reduced our power bills.

The criticism I received for building a land based marine system was extraordinary.

Jonathan

That is blatantly untrue Jonathan.

You were criticised for posting your project as if it were a boat project, when it was not.

 

[PaulRainbow]

Thanks. I'll finish writing up the design and post it for sure. It might give others some useful ideas, too. There will be a manual, too.

I have consulted with real EE's every step of the way, and have used AI's. I've learned a ton in the process, which has been fun.

The acid test, however, will be if I can get a real, reputable EE to give a written appraisal of the design which I can use with my insurance.

I would steer well clear of AIs

 

[dunedin]

MGN550 is totally irrelevant to us. It's a guidance paper for Lithium-Ion batteries.

Hands up everyone that has Lithium-Ion batteries on their boat.

But as far as I am aware, LiFePO4 is technically a Lithium-ion - just one that is much safer for boats than some other chemical formulae of Lithium-ion. Some use the term Lithium-ion to mean not LiFePO4, but I think that may be a marketing distinction rather than a technical one.
But happy to be corrected by a proper chemist.