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Battery Charging 'Concept' advice


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5 minutes ago, WotEver said:

Can you give a reference for this assertion?

'LiFePO4 fire' use that quote in google. 500 degrees for the electrolyte to catch fire, which can be achieved very quickly in a damaged battery.

 

Not my experience btw.

 

 

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1 minute ago, Pompey said:

no, thank you for posting.

 

Ever put a cover over a charging battery with a naked flame. Just to check how long it becomes unstable.

 

Let me get this straight. 

 

Provided I don't ever put a cover over my batteries with a naked flame, my boat is safe. Right?

 

 

 

 

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1 minute ago, Mike the Boilerman said:

 

Let me get this straight. 

 

Provided I don't ever put a cover over my batteries with a naked flame, my boat is safe. Right?

 

 

 

 

When have I said that?

 

If a battery is faulty it is faulty! Have you ever seen an electrical fire afloat, and how quick it can spread? 

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18 minutes ago, Pompey said:

'LiFePO4 fire' use that quote in google.

Top hit results in...

The LiFePO4 batteries are the safest type of Lithium batteries as they will not overheat, and even if punctured they will not catch on fire. ... Due to the oxygen being bonded tightly to the molecule, there is no danger of the battery erupting into flames like there is with Lithium-Ion.


So I repeat, what is your reference for LifePo4 batteries catching fire?

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10 minutes ago, WotEver said:

Top hit results in...

The LiFePO4 batteries are the safest type of Lithium batteries as they will not overheat, and even if punctured they will not catch on fire. ... Due to the oxygen being bonded tightly to the molecule, there is no danger of the battery erupting into flames like there is with Lithium-Ion.


So I repeat, what is your reference for LifePo4 batteries catching fire?

Then I am wrong, it wont be the first time, and am absolutely *sure wont be the last time. 

 

For my reference, if it stores energy then it can produce a sudden discharge, pun intended! They said the Titanic would never sink ?

Edited by Pompey
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2 hours ago, Pompey said:

I apologise, for 'Lithium burns with no air',  comment, it does, however water increases the' rapid destruction' of a Lithium based battery, LiFePO4's have been attributed to fires, the main cause that I can see is excessive damage. IIRC, if a Lithium based battery has its separator compromised it will either go into 'thermal runaway', or 'rapid destruction'.

 

If using Cells from a write off electric vehicle, how electrically safe would they be, especially on a boat?

 

A lot of good advice on here. I haven't read it all, and I haven't learnt all the all the lessons that life has to give.

 

Pompey. I am sorry but you are talking a load of rubbish. Your statements are either plain wrong or at best missleading.

 

'Lithium burns with no air   What on earth does this mean? Lithium metal burns only burns with oxygen. Yes, it doesnt need air if there are oxygen atoms around. In normal Li ion battery fires, the oxygen comes from the metal oxide content of the cathode so say cobalt oxide can decompose to provide the oxygen. In an LiFePO4 cell the oxygen could come from the iron phosphate but the oxygen is tightly bound so far far less likely to be available to support combustion. LiFePO4s are the safest of the Li ion batteries.  You have to understand though, there is normally no lithium metal in an Li ion battery, the Li is there in ionic form and so will be less likely again to combust. Metal lithium will only appear if the batteries are badly treated and we all avoid that...over charging and heavy discharging.

 

however water increases the' rapid destruction' of a Lithium based battery,   Where does the water come from? I have no water near my lithium batteries. I do not intend to have any water near my batteries. Once again it is metal lithium and water which causes a reaction but this would just make lithium oxide and would not cause an explosion or fire. It would just wreck the battery.

 

Lithium based battery has its separator compromised it will either go into 'thermal runaway', or 'rapid destruction'.   Once again, total misinformation. Separators do not get compromised. They dont fail. Thermal runaway can occur in Li ion batteries via short circuits caused by dendrite formation but very very unlikely in LiFePO4s as they are more robust than other Li systems and again only if misused. A further point you do not understand is that Li cells are built with a safety feature that will expel the electrolyte once the cells get to 100°C ish. The pressure cap will blow and the electolyte will be blown out therefore stopping any thermal runaway. This makes it very very difficult to get thermal runaway in a LiFePO4 cell. As long as LiFePO4 cells are not overcharged, or discharged/charged at high rate at very low temps then they are very very unlikely to go on fire.

 

If using Cells from a write off electric vehicle, how electrically safe would they be, especially on a boat?   What is special about a boat? When you buy 2nd hand batteries you test them to make sure they work. If they do then they can be installed anywhere. It is prudent to keep an eye on cell voltages to make sure that they are ok. The useage duty on a narrowboat is very sedate with very little potential for mechanical damage. I have said on here a number of times that I wouldnt use Li's on a lumpy water boat as that would have to withstand beating into a force 6 gale ....I just cant see them standing up to that hammering. Narrowboats are a bit different.

 

I haven't read it all, and I haven't learnt all the all the lessons that life has to give. My advice to you is to read it all and then come back and input. Your statements that come across as facts could influence others incorrectly.

 

My expertise on Lithium batteries comes from my own use of them on my narrowboat but also from my professional position with a company which is part of an Eu wide grant programme for the aerospace industry researching standards for the safe transport of Li ion batteries in passenger aircraft. Our company is doing a lot of work destroying batteries to explore their safety in the holds of aircraft. We now have a lot of experience in this area.

 

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40 minutes ago, TheBiscuits said:

I hope that's not a new forum rule.

 

It's going to go very quiet around here if it is enforced! :icecream:

Wouldn't it just

48 minutes ago, Dr Bob said:

Pompey. I am sorry but you are talking a load of rubbish. Your statements are either plain wrong or at best missleading.

 

'Lithium burns with no air   What on earth does this mean? Lithium metal burns only burns with oxygen. Yes, it doesnt need air if there are oxygen atoms around. In normal Li ion battery fires, the oxygen comes from the metal oxide content of the cathode so say cobalt oxide can decompose to provide the oxygen. In an LiFePO4 cell the oxygen could come from the iron phosphate but the oxygen is tightly bound so far far less likely to be available to support combustion. LiFePO4s are the safest of the Li ion batteries.  You have to understand though, there is normally no lithium metal in an Li ion battery, the Li is there in ionic form and so will be less likely again to combust. Metal lithium will only appear if the batteries are badly treated and we all avoid that...over charging and heavy discharging.

 

however water increases the' rapid destruction' of a Lithium based battery,   Where does the water come from? I have no water near my lithium batteries. I do not intend to have any water near my batteries. Once again it is metal lithium and water which causes a reaction but this would just make lithium oxide and would not cause an explosion or fire. It would just wreck the battery.

 

Lithium based battery has its separator compromised it will either go into 'thermal runaway', or 'rapid destruction'.   Once again, total misinformation. Separators do not get compromised. They dont fail. Thermal runaway can occur in Li ion batteries via short circuits caused by dendrite formation but very very unlikely in LiFePO4s as they are more robust than other Li systems and again only if misused. A further point you do not understand is that Li cells are built with a safety feature that will expel the electrolyte once the cells get to 100°C ish. The pressure cap will blow and the electolyte will be blown out therefore stopping any thermal runaway. This makes it very very difficult to get thermal runaway in a LiFePO4 cell. As long as LiFePO4 cells are not overcharged, or discharged/charged at high rate at very low temps then they are very very unlikely to go on fire.

 

If using Cells from a write off electric vehicle, how electrically safe would they be, especially on a boat?   What is special about a boat? When you buy 2nd hand batteries you test them to make sure they work. If they do then they can be installed anywhere. It is prudent to keep an eye on cell voltages to make sure that they are ok. The useage duty on a narrowboat is very sedate with very little potential for mechanical damage. I have said on here a number of times that I wouldnt use Li's on a lumpy water boat as that would have to withstand beating into a force 6 gale ....I just cant see them standing up to that hammering. Narrowboats are a bit different.

 

I haven't read it all, and I haven't learnt all the all the lessons that life has to give. My advice to you is to read it all and then come back and input. Your statements that come across as facts could influence others incorrectly.

 

My expertise on Lithium batteries comes from my own use of them on my narrowboat but also from my professional position with a company which is part of an Eu wide grant programme for the aerospace industry researching standards for the safe transport of Li ion batteries in passenger aircraft. Our company is doing a lot of work destroying batteries to explore their safety in the holds of aircraft. We now have a lot of experience in this area.

 

My expertise says my boat is surrounded by water. It is a boat.

 

As if spurting flammable electrolyte around the hot engine bay isnt bad enough, or inside the cabin 'as they are sealed', or just plane simple contaminating the water ways.

 

My budget doesnt run to a trial and error/ destruction situation, and I very well may be talking out of my backside,

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1 hour ago, Pompey said:

My expertise says my boat is surrounded by water. It is a boat.

So don’t throw your batteries into it. It’ll wreck them. They won’t catch fire or anything, they’ll just stop working, which is expensive. 
 

1 hour ago, Pompey said:

As if spurting flammable electrolyte around the hot engine bay isnt bad enough, or inside the cabin 'as they are sealed', or just plane simple contaminating the water ways.

Again, can you give a reference for this assertion?  I’ve certainly never heard of it happening on any boat, ever, anywhere in the world. 
 

1 hour ago, Pompey said:

I very well may be talking out of my backside

Unfortunately there’s no doubt about this. 

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Just now, WotEver said:

So don’t throw your batteries into it. It’ll wreck them. They won’t catch fire or anything, they’ll just stop working, which is expensive. 
 

Again, can you give a reference for this assertion?  I’ve certainly never heard of it happening on any boat, ever, anywhere in the world. 
 

Unfortunately there’s no doubt about this. 

LOL at the 3rd comment, I agree,makes no odds to me.

 

If you read your reply, you asserted it your self. How do you put out a lithium fire? as somebody facing that fire, not sat behind a desk saying, ohh I didnt think that would happen!

 

I would treat my batteries like eggs! They are valuable, not a destruction test,

 

Oh hang on maybe that was what the egg was invented for. 

 

I love talking out my ass, and getting intelligent people to respond!

 

 

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2 minutes ago, Mike the Boilerman said:

 

Ah so you're doing it deliberately. 

 

Thanks for the confirmation.

 

 

Maybe there should be a call for Pumpey's ban - by his own admission he does contravene the much enforced rules :

 

"You will not use CWDF to post or reference to any material anywhere on the site that is knowingly false and/or defamatory, aimed to deceive or ridicule, abusive, vulgar, hateful, harassing, disruptive, intimidating, threatening, inflammatory, obscene, profane, sexually oriented, bullying or invasive of a person's privacy"

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1 minute ago, Alan de Enfield said:

Maybe there should be a call for Pumpey's ban - by his own admission he does contravene the much enforced rules :

 

"You will not use CWDF to post or reference to any material anywhere on the site that is knowingly false and/or defamatory, aimed to deceive or ridicule, abusive, vulgar, hateful, harassing, disruptive, intimidating, threatening, inflammatory, obscene, profane, sexually oriented, bullying or invasive of a person's privacy"

 

You know that won't happen, given Team Mod's record of only haphazardly applying the written rules, and occasionally applying rules that don't even exist.

 

 

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11 hours ago, Pompey said:

 

As if spurting flammable electrolyte around the hot engine bay isnt bad enough, or inside the cabin 'as they are sealed', or just plane simple contaminating the water ways.

 

My budget doesnt run to a trial and error/ destruction situation, and I very well may be talking out of my backside,

Pompey. Once again utter rubbish.

 

You do not get 'spurting flammable electrolyte'. If you heat a Li ion battery with a blow torch, then the heat is spread out over the cell, the pressure relief valve blows and the electrolyte escapes as a gas and does not ignite. Look at the chinese videos in this thread. The gas/smoke coming out of the batteries is the electrolyte. It doesnt catch fire at these temperatures. To get a thermal runaway you have to have a point source of heat at 500°C which only happens on a short etc.

Have a look at a thread from last year that I posted

Since that thread started ...Nobody ..... has come back with ANY links to fires in LiFePO4s. The stability of the cathode material is so much better than other Li ion batteries. The messages that I can summarise are as follows:-

1) dont buy cheap chinese batteries as they could have manufacturing defects - even then LiFePO4s are far more stable than other Li ion.

2) dont misuse your batteries ie overcharge to stop dendrite formation

3) if you do have a boat fire then the flammable material in a LiFePO4 bank is only the same as if it was wood/paper/plastic so the boat is still going  to get destroyed wether you have Li's or not.

In my opinion the risk of fire in LiFePO4 is very very very low to zero if managed properly. If you think otherwise then please provide data.

 

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18 minutes ago, Dr Bob said:

Pompey. Once again utter rubbish.

 

Just musing about what is going on here with this nice Mr Pompey.

 

I suspect Mr Pompey is accustomed to chatting to boaters on the towpath and with customers, and average boaters not being very clued up electrically he has become accustomed to people taking his dodgy advice and scaremongering tales about how dangerous LiFePO4 batteries at face value and without question. He probably gets thanked for his advice and warnings even though much of his advice on pretty much any electrical topic will be similarly riddled with half-truths and stuff that is plain wrong.

 

Now he turns up here peddling the same load of twaddle and is rather taken aback to be challenged to produce evidence to support the incorrect assertions that trip from his tongue in such an easy and practiced way. Quite a shock I would imagine. Its a curious schtick he responds with I've not seen before, "ok hands up so I am wrong about that particular bit, but who knows everything in life, certainly not me".... but learning nothing and carrying on handing out the duff advice....

 

 

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2 hours ago, Alan de Enfield said:

Maybe there should be a call for Pumpey's ban - by his own admission he does contravene the much enforced rules :

 

"You will not use CWDF to post or reference to any material anywhere on the site that is knowingly false and/or defamatory, aimed to deceive or ridicule, abusive, vulgar, hateful, harassing, disruptive, intimidating, threatening, inflammatory, obscene, profane, sexually oriented, bullying or invasive of a person's privacy"

I think we know how much notice is taken of the "knowingly false" rule.

 

I could guess that something isn't "knowingly false" until the poster "knows it is false".

 

It could be argued that, as soon as this guy has been convinced that what he us saying is false, he holds his hands up and accepts it.

 

ergo, no rule has been broken ???

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33 minutes ago, Richard10002 said:

I think we know how much notice is taken of the "knowingly false" rule.

 

I could guess that something isn't "knowingly false" until the poster "knows it is false".

 

It could be argued that, as soon as this guy has been convinced that what he us saying is false, he holds his hands up and accepts it.

 

ergo, no rule has been broken ???

 

I'd suggest that this proves that he is knowingly providing incorrect information :

 

 

12 hours ago, Pompey said:

I love talking out my ass, and getting intelligent people to respond!

 

 

 

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On 13/01/2020 at 10:00, Dr Bob said:

Pompey. Once again utter rubbish.

 

You do not get 'spurting flammable electrolyte'. If you heat a Li ion battery with a blow torch, then the heat is spread out over the cell, the pressure relief valve blows and the electrolyte escapes as a gas and does not ignite. Look at the chinese videos in this thread. The gas/smoke coming out of the batteries is the electrolyte. It doesnt catch fire at these temperatures. To get a thermal runaway you have to have a point source of heat at 500°C which only happens on a short etc.

Have a look at a thread from last year that I posted

Since that thread started ...Nobody ..... has come back with ANY links to fires in LiFePO4s. The stability of the cathode material is so much better than other Li ion batteries. The messages that I can summarise are as follows:-

1) dont buy cheap chinese batteries as they could have manufacturing defects - even then LiFePO4s are far more stable than other Li ion.

2) dont misuse your batteries ie overcharge to stop dendrite formation

3) if you do have a boat fire then the flammable material in a LiFePO4 bank is only the same as if it was wood/paper/plastic so the boat is still going  to get destroyed wether you have Li's or not.

In my opinion the risk of fire in LiFePO4 is very very very low to zero if managed properly. If you think otherwise then please provide data.

 

Thanks for your decent reply Dr. Bob, I understand and never intended to come across as an expert, and as I have previously said, I wasn't making, or at least didn't intend to make a statement of fact. More of a 'as I understand comment'.  

 

From the reaction I feel I have received, I may as well bitten the head of a cute fluffy kitten, and streamed it live on CBBC. Not necessarily comments from you.

 

FYI, the 'I love talking out my ass comment' was a sarcastic remark drawn out of frustration. However some people choose to believe that statement,  even when I am being accused of spreading mis-information. So at that point I felt it really didn't matter what I said.

 

Keep up the good work, good luck.

In my opinion if everything on a boat is managed properly, then there will never be an incident of any sort, however not everybody does manage a boat properly. 

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