Switch from AGM to Lith-ion

[a64pilot]

No clue. My guess would be what I like to call inertia. It takes so long and is so expensive to get anything through certification, that even if during the certification process you discover a fault, it’s most often wiser to drive on with the cert process, to “fix” it later. You don’t dare interrupt the cert process as often you basically have to get back into line if you will.
But Boeing I’m certain is at least an ODR organization, meaning that they basically self certify.
FAA in truth couldn’t handle a cert program that big, the FAA has become over time what all Government agencies do, that is get real heavy with administrators and the like and real thin on actual Engineers, and the Administrators who have zero technical knowledge, make the decisions.

Problem often occurs with the Owners and Marketing not wanting to spend the time and money to “fix” something they in their expertise feel isn’t a problem, it’s certified, right?

This explains it well, if you’ll read it. A new term was coined to explain the shuttle disaster, it’s called normalization of deviation.
Or I think of it as the day you put management / administration in charge of safety.
https://sma.nasa.gov/docs/default-so...rsn=c5421ef8_4

[Kenomac]

Originally Posted by Dockhead

Absolutely right.


I'd like to have about 600 amp/hours * 24v of usable power on my present boat and according to how she is equipped and how I use her. A future boat, with electric cooking etc., will need more. 600 amp/hours of usable power would require about 24 T105's, which weigh a whopping 672kg or more than 2/3 of a metric tonne. Weight is not a big issue? Nonsense. That kind of weight will slow down even a large boat, and will have a negative effect on stability if you can't get the batts low enough (and get them low enough, and you have a risk of flooding them if you have a leak).


The same amount of usable power can be stored in about 180kg of LiFePo cells for a saving of nearly half a tonne. That is a hell of a difference. That's 2.5% of the entire displacement of my boat -- just the savings. And the difference in volume gives you totally different options about where to install them.



And as someone else wrote -- I can't imagine why ANY catamaran, uses lead batteries.

Curious. Why do you feel like you need 600ah of usable power? Our 53 remains in anchorages 4-5 months per year with a 400ah 24v bank and 450w of solar.and never drops below 80% on a daily basis. This covers all electric cooking, watermaking, laundry, coffee making, refrigeration, everything; and recovers to 100% daily. We may only burn 1 gallon of diesel per week to make hot water when used for four hours at 1 liter per hour. Our 62 is the same usage with a 800ah 24v Rolls bank.

Why do you need so much? 6x as much as we use on the same size boat.

Note: Sometimes it’s more cost effective to improve efficiency rather than throwing money at a larger bank. Here we are pictured at anchorage today with our boom out to eliminate sun shading of the solar and provide an attachment point for our stabilizer. Orinoco Flo did three loads of laundry today, and we’re presently at 91% SOC.

[Dockhead]

Originally Posted by Kenomac

Curious. Why do you feel like you need 600ah of usable power? Our 53 remains in anchorages 4-5 months per year with a 400ah 24v bank and 450w of solar.and never drops below 80% on a daily basis. This covers all electric cooking, watermaking, laundry, coffee making, refrigeration, everything; and recovers to 100% daily. We may only burn 1 gallon of diesel per week to make hot water when used for four hours at 1 liter per hour. Our 62 is the same usage with a 800ah 24v Rolls bank.

Why do you need so much? 6x as much as we use on the same size boat.

Note: Sometimes it’s more cost effective to improve efficiency rather than throwing money at a larger bank. Here we are pictured at anchorage today with our boom out to eliminate sun shading of the solar and provide an attachment point for our stabilizer. Orinoco Flo did three loads of laundry today, and we’re presently at 91% SOC.

Well, it's approximately 3x, not 6x as much as you have.


600 amp/hours might be slight overkill, it's more than 24 hours of consumption, but did anyone ever complain about having too much power? If I change to lithium power, I would double the inverter capacity and stop cooking with gas altogether. It would be nice to be able to run all that for more than 24 hours without running the generator (no solar on my boat).


But the main reason is for multiday passages under sail. The boat uses more power when sailing with all the nav gear working and the pilot running. I hate to shorten sail when we're flying on a close reach in order to avoid too much heeling to run the generator. Actually I find that running the generator at all when on long passages under sail to be disturbing and disruptive of the rhythm and atmosphere.


So I don't know. I also don't know how long I will have this boat so don't know what I can justify spending. Maybe 400 amp/hours would be enough, but surely not less than that. That would just about get me to 24 hours at my current rate of usage.

[Kenomac]

Originally Posted by Dockhead

Well, it's approximately 3x, not 6x as much as you have.


600 amp/hours might be slight overkill, it's more than 24 hours of consumption, but did anyone ever complain about having too much power? If I change to lithium power, I would double the inverter capacity and stop cooking with gas altogether. It would be nice to be able to run all that for more than 24 hours without running the generator (no solar on my boat).


But the main reason is for multiday passages under sail. The boat uses more power when sailing with all the nav gear working and the pilot running. I hate to shorten sail when we're flying on a close reach in order to avoid too much heeling to run the generator. Actually I find that running the generator at all when on long passages under sail to be disturbing and disruptive of the rhythm and atmosphere.


So I don't know. I also don't know how long I will have this boat so don't know what I can justify spending. Maybe 400 amp/hours would be enough, but surely not less than that. That would just about get me to 24 hours at my current rate of usage.

I think you need to take a good hard look at energy conservation and efficiency onboard your boat before throwing money at more capacity. Our new Raymarine radar, two chart plotters and instruments use hardly any amps, the Italian Frigoboat refrigeration... very low consumption, electric induction, infrared and microwave cooking also very low.. we haven’t purchased propane in over 7 years. Spectra watermakers.. low, LED lighting... insignificant. How low??? Low enough that with 450w of solar, our daily consumption equals the solar input. So definitely lower than 200ah.

[MikeFergie]

I have 600amp hours of gel batteries on my cat and find that hard sailing eats the amp hours. 2 weeks ago for example I started an open ocean trip leaving my anchorage at 100% on the batteries and pulled up sails and set the autopilot and off we went. At 3am in the morning my Victron battery monitor started alarming and my voltage was down to 12,1v. This according to the battery tables tells me my batteries were down to 50%.

That’s a lot of amps for 17 hours of sailing. I started up one of my Yanmar’s and run it above idle til sunrise to allow the alternator to put enough power back.

This past weekend I ran the water heater in my washing machine for the first time. As it kicked in my Victron was showing me 1,65Kw/hour and after 10 minutes the alarm started as my voltage was showing 11,8v. At the end of the heat cycle the machine had consumed 50 amp hours and the voltage came back up to12,6v.

I will be shortly changing to 400amp hours of lithium ion phosphate batteries and at year end will increase this to 600amp hours for full time cruising next year. I have met 3 cruisers that have changed over a few years ago and none have had any problems. The words we don’t even have to bother worrying about the batteries. “They just work”

[Q Xopa]

Originally Posted by Dockhead

There is a lot of discussion about that in the aviation engineering forums -- a lot of people asking the same question.


I have no idea what the answer is, but we have a professional from aviation on this forum (and maybe more than one), A64Pilot, maybe he will weigh in with some actual knowledge. Engineering is what Boeing DOES, so I can't imagine that it was some kind of really dumb mistake with something really obvious, but I don't have any actual knowledge.

Being an aviation engineer I can say that most aircraft batteries, atleast larger turbine aircraft, are NiCads. These are known to have thermal runaways. But this risk is mitigated by proper maintenace practises.

Or I guess if your not comfortable how dangerous they can be then you can decline commercial air travel.

This hysteria over Lithium batteries, really needs to be kept in perspective.

You do realise that the car you ride in has an explosive gas tank in the back of it.

Maybe you are aware sailing can also be a dangerous pusuit.

Or that heart diesese, cancer and road accidents are by far the biggest killers in our society.

I dont see anyone advocating shunning flying, cars or McDonalds fast food.

As with NiCads, Sailing, cars, fast food indeed most things in life, it all comes down to knowing the dangers and managing the risks.

A bit of sensationalism and dramatic effect makes for good forum fodder.

Carry on.

[RaymondR]

Originally Posted by a64pilot

No clue. My guess would be what I like to call inertia. It takes so long and is so expensive to get anything through certification, that even if during the certification process you discover a fault, it’s most often wiser to drive on with the cert process, to “fix” it later. You don’t dare interrupt the cert process as often you basically have to get back into line if you will.
But Boeing I’m certain is at least an ODR organization, meaning that they basically self certify.
FAA in truth couldn’t handle a cert program that big, the FAA has become over time what all Government agencies do, that is get real heavy with administrators and the like and real thin on actual Engineers, and the Administrators who have zero technical knowledge, make the decisions.

Problem often occurs with the Owners and Marketing not wanting to spend the time and money to “fix” something they in their expertise feel isn’t a problem, it’s certified, right?

This explains it well, if you’ll read it. A new term was coined to explain the shuttle disaster, it’s called normalization of deviation.
Or I think of it as the day you put management / administration in charge of safety.
https://sma.nasa.gov/docs/default-so...rsn=c5421ef8_4

There could be another reason for the self certification trend.

An inquiry by the Brit government after the Piper Alpha oil platform disaster found many deficiencies in both design and operating procedures had contributed to the disaster. However the oil company was able to say they were innocent of any wrong doing as they had complied with all government requirements which were prescribed at that time and that if there was any fault it was in the inadequasy of the regulation.

To avoid being held responsible in this manner the government changed the safety certification to one of self certification via the "safety case".

Under the safety case regime the oil company has to identify any safety related issues and their response thereto. If there is an incident from an unidentified source the government in then in a position to claim it was entirely the oil companies fault as they had failed to identify the problem in the safety case.

In this manner the bureaucrats authority is preserved without them having to bear any responsibility.

[Q Xopa]

Originally Posted by a64pilot

No clue. My guess would be what I like to call inertia. It takes so long and is so expensive to get anything through certification, that even if during the certification process you discover a fault, it’s most often wiser to drive on with the cert process, to “fix” it later. You don’t dare interrupt the cert process as often you basically have to get back into line if you will.
But Boeing I’m certain is at least an ODR organization, meaning that they basically self certify.
FAA in truth couldn’t handle a cert program that big, the FAA has become over time what all Government agencies do, that is get real heavy with administrators and the like and real thin on actual Engineers, and the Administrators who have zero technical knowledge, make the decisions.

Problem often occurs with the Owners and Marketing not wanting to spend the time and money to “fix” something they in their expertise feel isn’t a problem, it’s certified, right?

This explains it well, if you’ll read it. A new term was coined to explain the shuttle disaster, it’s called normalization of deviation.
Or I think of it as the day you put management / administration in charge of safety.
https://sma.nasa.gov/docs/default-so...rsn=c5421ef8_4

Yes the travelling public would be 'shocked' of they knew of the vested interests involved in the Certification process, well maybe for a few minutes.

But the reality is the FAA dont want kill industry and jobs at a darling US company like Boeing.

But in a rush to keep Boeing competitive by getting their 737 MAX into the market ahead of their arch competitors.

Shortcuts were taken by Boeing who were tasked with 'self regulation' by the FAA.

So they fitted the 737 with larger more efficient fan engines. But they wouldnt fit without dragging on the tarmac. So the clever engineers solved the problem by mounting the engines higher on the wing. This raised the thrust pitching the nose up. No worries they solved this with software pitching the nose back down.

This was all fine until it didnt work.

They also cleverly marketed this new variation as minimal pilot conversion training so didnt explain these new changes and additions to newly converted pilots. Pilot training is expensive. So airlines want to keep this expence to a minimum to keep ticket prices own.

Of course the travelling public dont want to pay for more FAA regulation or pilot training when they buy their tickets.

Sorry for the thread drift.

[Time2Go]

Got to agree with Dockhead on this.
I’ve been on boats where every amp has to be
counted and rationed, Its not fun
Also been on boats where the frig has to be cycled
on and off leaving all stuff inside suspect.
Then been on boats with large Lithium banks
and amps were just not a concern.
Large amount of usable as a percentage of capacity
plus the ability to charge at high rate is just a plain winner.
To the naysayers, our boats are now complex
Electro,Electronic,Manual Machines
Just learn it and enjoy some Ice-Cubes
I was recently on a delivery where we lost all
charging ability (engine & genset)
to bad fuel and sailing in the stone age
for days on end is no fun
Load up the amps and learn the new stuff
It’s like going from a rotary dial phone on the wall
to a new smart phone
Not that bloody hard to do
Cheers
Neil

[Q Xopa]

Originally Posted by Time2Go

Got to agree with Dockhead on this.
I’ve been on boats where every amp has to be
counted and rationed, Its not fun
Also been on boats where the frig has to be cycled
on and off leaving all stuff inside suspect.
Then been on boats with large Lithium banks
and amps were just not a concern.
Large amount of usable as a percentage of capacity
plus the ability to charge at high rate is just a plain winner.
To the naysayers, our boats are now complex
Electro,Electronic,Manual Machines
Just learn it and enjoy some Ice-Cubes
I was recently on a delivery where we lost all
charging ability (engine & genset)
to bad fuel and sailing in the stone age
for days on end is no fun
Load up the amps and learn the new stuff
It’s like going from a rotary dial phone on the wall
to a new smart phone
Not that bloody hard to do
Cheers
Neil

Im all for it.

Those that love the true essence of sailing without out the new fancy niceties I admire.

Personally not for me if I have a choice. I have spent enough of my life, (like now infact), in 3rd world countries that others refuse to go to.

Im with Dockhead, why skimp if you dont have to?

Each to their own, I guess.

[Dockhead]

Originally Posted by Q Xopa

Im all for it.

Those that love the true essence of sailing without out the new fancy niceties I admire.

Personally not for me if I have a choice. I have spent enough of my life, (like now infact), in 3rd world countries that others refuse to go to.

Im with Dockhead, why skimp if you dont have to?

Each to their own, I guess.

The irony is that with a really adequate lithium battery bank, you end up with more "true essence of sailing" anyway, because you can sail for more than 24 hours without having to faff around getting the genset up, and then having to live with the sound of it, while you are reefed down having killed your speed, and just in general you think a lot less about power and more about sailing.


Of course you can also just do without a bunch of electrical gear, wash your clothes in a bucket, use a wind vane, etc., but why if you don't have to?

[Two Skippies]

Not wishing to start another Battery thread, so I hope it’s ok to put this here.
I found this on my FB page and thought I’d see what people think.
It’s kind of related to this thread anyway.

[FlyingScot]

600 ah @ 24 v nominal is a lot compared to most cruising boats from what I see and read about.

Those are large numbers. I have 450ah @ 12v FF Oasis. When my 1440w solar is near max (90-100 amps charging), I barely reach the recommended minimum of 0.2C. We have a BD80 fridge, an Engel fridge, and we have a whole bunch of laptops, ipads, gadgets plugged in all the time. Two inverters, one always running. Of course, all lighting is LED, radar is new style, etc. We try to be efficient. Heating water is our indulgence.

Huge battery banks have to be recharged by something. Many forget this side of the equation. Our system is set up to for 20-40% DOD occasionally dipping below 50%.

[Kenomac]

Originally Posted by Dockhead

The irony is that with a really adequate lithium battery bank, you end up with more "true essence of sailing" anyway, because you can sail for more than 24 hours without having to faff around getting the genset up, and then having to live with the sound of it, while you are reefed down having killed your speed, and just in general you think a lot less about power and more about sailing.


Of course you can also just do without a bunch of electrical gear, wash your clothes in a bucket, use a wind vane, etc., but why if you don't have to?

So, you guys think we’re living in the stone age here in our Oysters doing laundry in a bucket? I assure you, we’re not. The end result you desire can also be achieved much more cheaply via added efficiencies was the point I was trying to make. There’s no reason to mock those of us who are trying to help, some of us already have the answer you seek.

But it’s your money.... do what you like with it.

[bcboomer]

Originally Posted by Two Skippies

Not wishing to start another Battery thread, so I hope it’s ok to put this here.
I found this on my FB page and thought I’d see what people think.
It’s kind of related to this thread anyway.

I think you will find that those are not the safe LiFePO4 chemistry.