Low priced LiFePO4 Batteries vs High priced

[Simi 60]

Originally Posted by goboatingnow

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Hence since the boat was built to the RCD including its electrical system. It’s disingenuous to suggest a full lithium install is simply a like for like battery replacement. It clearly is not.

Hence the need for disclosure

EU problem
Not AU.

[goboatingnow]

Originally Posted by Simi 60

EU problem
Not AU.

SUre , my point was I’m firmly of the belief that lithium upgrade should be disclosed to ones insurers

[Apollo19.5]

Recently insured with Pantenious and yes, they asked regarding lithium onboard. I asked them what their current stance is on them. They are in a 'hold' mode with them and hence the 50% payout relating to damage originiating from the electrical system. They did say that it will be reviewed, but if the system is professionally designed and installed, the clause will be removed. He did say that a DIY system that is signed off by a qualified person can be ok. Apparently there has been quite a few claims in this area (possibly dodgy install/equipment?). I have a newish AGM system aboard so it doesnt affect me however I will be wanting to move to Lithium once these get tired.

[goboatingnow]

In my case I have provided evidence to my insurers I am a professional therefore I beehive Pantenious will accept that. There’s is evidence their thinking is evolving.

[s/v Jedi]

Originally Posted by Apollo19.5

Recently insured with Pantenious and yes, they asked regarding lithium onboard. I asked them what their current stance is on them. They are in a 'hold' mode with them and hence the 50% payout relating to damage originiating from the electrical system. They did say that it will be reviewed, but if the system is professionally designed and installed, the clause will be removed. He did say that a DIY system that is signed off by a qualified person can be ok. Apparently there has been quite a few claims in this area (possibly dodgy install/equipment?). I have a newish AGM system aboard so it doesnt affect me however I will be wanting to move to Lithium once these get tired.

There has not been one single claim for a fire caused by a LFP battery.

[newhaul]

Originally Posted by goboatingnow

In my case I have provided evidence to my insurers I am a professional therefore I beehive Pantenious will accept that. There’s is evidence their thinking is evolving.

Well if they are like 99% of insurance companies they will not accept your word on anything .
Conflict of interest and all . I am a retired shipwright and surveys are simple and easy to do but I can't do my own for the aforementioned reason .

[UFO]

Originally Posted by goboatingnow

Lloyds are not retail insurers and can’t retail into Europe. I’m with Pantenious one of the biggest

No they clarified only 50% if there lithium fitted and there’s an electrical fire.

I do believe once they accept my qualifications and verify the install design they will drop that deduction it looks that way from the ongoing correspondence.

Just to clarify - Even if the electrical Fire was NOT caused by the lithiums, but by another source on the boat they still only pay 50%?

[goboatingnow]

Originally Posted by newhaul

Well if they are like 99% of insurance companies they will not accept your word on anything .

Conflict of interest and all . I am a retired shipwright and surveys are simple and easy to do but I can't do my own for the aforementioned reason .

No it’s not shaping up like that. I have demonstrable Domain expertise in industrial lithium. They are prepared to accept that

Any “ local professional “ would not have the lithium expertise and hence couldn’t “ sign off” and they know that

[newhaul]

Originally Posted by goboatingnow

No it’s not shaping up like that. I have demonstrable Domain expertise in industrial lithium. They are prepared to accept that

Any “ local professional “ would not have the lithium expertise and hence couldn’t “ sign off” and they know that

Read the ultra fine print then

[goboatingnow]

Originally Posted by newhaul

Read the ultra fine print then

It’s a form of acceptance letter. My goal is no deductions due to lithium accidents.

[newhaul]

Originally Posted by goboatingnow

It’s a form of acceptance letter. My goal is no deductions due to lithium accidents.

My goal is. No lifepo4 accidents.

[Phil_Fr17]

Looks like we (you) are drifting off topic, right?

[CaptainRivet]

Originally Posted by Anders

Pantaenius is definitely the biggest boat insurance company in Europe.

And Pantaenius getting worse and worse in Europe too. Worked in insurance a lately met a couple of GMs and CEO. Their statement was, before no big issues but since 1.5year when we have Pantaenius as third party liability provider to deal with in a claim we right away involve a laywer.
Same my own experience with them, crap....

[T1 Terry]

Originally Posted by s/v Jedi

You are correct, 3.4V/cell termination voltage during charging would undercharge the battery. But what if this is taken as an absorption voltage for let’s say 2-4 hours?

I’m not sure how they charge to that voltage, but I do know that you can fully charge (or 99.5% or so) at 3.4V/cell when it is held in absorption long enough.

The wish to use a CC/CV charge regime as described by cell manufacturers looks great on paper but it is designed for EV applications, where you charge the car and then it sits until driven. This is not how boats work, they use power continuously and when the battery is full we want to keep using solar power, not switch that off and use battery power instead. We only want to use battery power when the sun comes down and we lose solar power for the night.

The only way to achieve that is by configuring a float voltage that isn’t so low that power from solar is wasted. During years of living aboard with LFP and solar, I have found that 3.3V/cell is the ideal float voltage. It does discharge the battery to 92% but most of the solar power is used.

Our charge settings:

Absorption voltage: 3.45V/cell
Absorption current: I can reach 0.5C, have 1,875W solar for a 10.5kWh battery.
Absorption time: fixed 2 hours

Float voltage: 3.3V/cell

When the absorption charge finishes and the controllers switch to float, you see all power coming from the battery instead of solar. This is good because it’s better for the LFP to not be kept at full charge. When they are down to 97% SOC, solar delivers most of the power again and at low 90’s SOC solar takes 100% of power consumption.

The BMV is configured to trigger “fully charged” a couple mV below absorption voltage as described in the manual. It works perfect.

So here are the results: maximum cell deviation after battery was installed was 4mV. After two years of cycling with settings as described above, with no cell balancing of any kind, maximum cell deviation was 8mV. I packed my cell balancer because I don’t think it’s useful to do this for 4mV.

I must add that this battery is an 8s configuration with perfectly matched cells.

3.4v will hold the cell close to fully charged, but it won't fully charge a cell. Even LFP cells have an internal resistance, the 0.05v above the standing cell voltage is required to add more capacity into the cell, it is just so slow it's like watching grass grow. However, 0.1v above the standing voltage will greatly increase the charge rate, if solar is the charging source, then 13.8v float will trickle more capacity in for as long as the sun shines, but it stops when the sun is no longer on the panels.
This is different to shore power charging or mains charging as it's known in the land based community. That will hold the 0.05v above the standing 99% charged point and gradually push the cell that is closest to full capacity to an even higher voltage, at the expense of the lowest capacity cell. This drives an out of balance situation and this is the reason for the blanket declaration to not float charge lithium batteries.
If you can drop the charge rate to equal or less than the active balancer capacity balancer capability, then as long as the charger isn't still running for days, there will be no harm done to the cells.
Resistor based balancers aren't the same as active balancers, these things will just keep generating heat until something fails, they are just a problem waiting to show up at the very worth time.

Quality chargers have an auto "storage mode" they drop into once they see a percentage of charge current over a number of hrs. This can be set to what ever percentage of the battery capacity you want, if you do have resistor type cell balancing though, keep the percentage below the current flow all cells in balance mode would draw.
Those chargers with minimum current switching from absorption to float can have the float voltage set as the storage voltage, just remember to set the "rebulk" to a higher point than the difference between storage voltage and absorption voltage ... or the poor controller will develop a migraine and eventually refuse to do anything Yes, I've seen more than one system set up that way, some "off grid" gurus need to go back to school at basic maths level.

Once the voltage differential is reached to kick the charger back into "rebulk" it generall means there is a load greater than the charger capability to hold the battery voltage above the storage/float voltage and the system will go back through the same procedure . This method of ending absorption voltage is far better than the set time method, unfortunately, not all chargers have this function.

Battery management systems like the "Electrodacus" (made by a Canadian go fund me type developer) has the smarts to bring the cell voltage up to what ever you want to program into it, then drop back to a lower cell voltage for the rest of the day. The great thing about this idea, the cell voltage is the controlling factor, not battery voltage, so much better conditions to promote long cycle life.

T1 Terry

[T1 Terry]

Originally Posted by UFO

When I get a chance I will do that.


The reason it is set to that is the the company that sells the BMV state to exactly that in the manual and also by email when I talked to them.


Why would they state that if its a major issue as you say?


Here is a Link to them:



https://123electric.eu/products/123smartbms-gen3/

The problem I see with these type of boards is they are connected to the cell terminal and use this as a heat sink for the resistor they use to put a load across the cell to burn some of the capacity off.
The only reason I can see to set such low cell voltages is to minimise they amount of actual balancing these boards are doing, but at the expense of ever diminishing battery capacity.
This is the reason I'm not a fan of resistor type cell balancers and promote active balancing that moves the capacity from the high voltage cell to the lower voltage cells until the voltage is within .... generally 5mV, or though I have seen the ones we have been using get the balance to 0.02 volts between highest and lowest .... then it turns off and won't restart until it senses a difference of 15mv, then it goes back into it's rebalancing mode.
With the Electrodacus unit, the differential voltage the balancer stops at and the differential voltage it will restart can be set in the advanced menu ..... great for those who have developed some understanding of just how their system is functioning.
None of these really smart BMS systems are really suitable for drop in batteries linked in parallel. The top would need to come off to access each cell to wire them up, then one system for each battery. If yo are going to go as far as popping the top off the drop in batteries, better to build each battery with the cells paralleled to get the capacity you want, then link them in series .... No longer a quick and easy drop in system eh ...... but quick, easy, cheap, reliable,long lasting are not words that go together when talking about a house battery that you will be risking your life on ......

T1 Terry