bs3911 compared to CCA for starter batteries

[Refueler]

Just to reiterate with lithium batteries (any sort or size) you must have an accurate way to cut off charge completely at the correct voltage (around 4.1v) for each individual cell. Or risk damaging the cell or having a huge fire. ol'will

Correction please .... Lithium cells Max voltage range from 2.5V up to 4.35V depending on 'chemistry'. The LiFe / LiFePo are usually 3.65V max .... per cell.

 

[Zing]

It's not like i do any of this for a day job ?

Oh did this recently on a large cat' that has just sailed half way around the UK



This is also connected to two engines and a 3kw Victron multiplus

A different scenario entirely. Those are packaged battery packs bought and then installed. We are discussing making a pack. A different skill set.

 

[Zing]

Those LiFePo4 you highlight are 3C max discharge .... that's 40 x 3 = 120A rate .... combining the cells does not in fact increase that as the cells themselves cannot tolerate higher rate. In fact in reality - C rates are often 'optimistic' .......

No, they are 10C for 30 secs If I recall correctly. It won’t mention it, but they can do far more than that briefly. The issue isn’t going to be CCA. A smaller battery even will cope. It’s wise to have a few amps capacity for good measure.

 

[Refueler]

No, they are 10C for 30 secs If I recall correctly. It won’t mention it, but they can do far more than that briefly. The issue isn’t going to be CCA. A smaller battery even will cope. It’s wise to have a few amps capacity for good measure.

I am well aware that Lithium's usually quote a max constant and a max burst rate .... but burst rates are usually rated at 10 secs not 30. They also are seriously damaging to ANY Lithium based cell ...

Maybe your 'wonder cells' do quote 30secs burst ... but I have to say that reading your defence of Lithium - I am glad that most people understand not to follow your example ...

 

[Zing]

I have. To get a 12v pack suitable for direct use in a 12v boat system costs according to your link around £600 with VAT. A similar product without all the hassle of building it up such as this https://www.intellitecmv.com/collections/lithium-batteries/products/lfp-powerbrick-12v- is available off the shelf from a reliable supplier in the UK for £426. This both smaller and lighter and has a built in BMS

Still not recommended for engine start being a deep cycle battery and nearly 3 times the price of my Odyssey which is specifically designed for engine start which is again smaller and only weighs 4kgs more (or 3kgs more than your suggestion.

No, that is incorrect, you didn’t read it closely then. It has a peak discharge current more than adequate for the job. If they measured CCA

Also, that retailer actually suggests it as a starter battery.

There is no such thing as a deep cycle lifepo4 battery. Engine starting and deep cycle incorporate the same cells.

 

[Zing]

I am well aware that Lithium's usually quote a max constant and a max burst rate .... but burst rates are usually rated at 10 secs not 30. They also are seriously damaging to ANY Lithium based cell ...

Maybe your 'wonder cells' do quote 30secs burst ... but I have to say that reading your defence of Lithium - I am glad that most people understand not to follow your example ...

You mean most people like BMW, Ducati, Aprilia, Suzuki, Kawasaki and Honda?

 

[Refueler]

You mean most people like BMW, Ducati, Aprilia, Suzuki, Kawasaki and Honda?

Apples and Oranges .... me 'ol fruit .......

 

[geem]

I can’t see the need for a class T on a lithium battery. They don’t fail to dead short. Why do you suggest it?

Starter circuits are often not wired with fuses, but I think it a good idea to have one and if you have one already, you wouldn’t need another, so no added complexity. They are cheap anyway.

If a charger fails you have a dead battery, just as you do with lead. If it’s ok for lead, it’s no different for lithium and with no significantly greater risk.

I did suggest not using the alternator ideally, or you must then do it with a matched regulator/rectifier to get the ideal charge state. I.e. not full. But there are better ways. A charge controller or better still a battery to battery voltage supply on a timer. Cheap and almost zero risk of overcharge. The battery looked after like that will not need a BMS. Will not need protecting from discharge, will not overcharge, will not go out of balance and will be at least as safe as lead.

I don’t agree there is a lot more than I am saying than this for a starter battery.

That said, it’s easier to stick with what you are used to and unless you enjoy this sort of thing or particularly value lithium’s advantages in this application that I mentioned then I don’t think you should bother.

With all due respect. You have a lot to learn about using lithium batteries safely.
I am actually working on a lithium project. Liquid cooling them for high ambient operation. I do know a thing or two about lithium. Everything I suggested you need is common knowledge amongst those experienced with this technology. The internet is full of people telling you you don't need stuff. It's also full of tales of woe where installation like the one you are suggesting went horribly wrong.
Solar regulators don't necessarily fail dead. They can lose their control and charge at full solar output. You need to do some research on lithium before you start lecturing those that know how to do it safely. You are a good example of why insurance companies insist on proffessional installation of lithium batteries

 

[Tranona]

No, that is incorrect, you didn’t read it closely then. It has a peak discharge current more than adequate for the job. If they measured CCA

Also, that retailer actually suggests it as a starter battery.

There is no such thing as a deep cycle lifepo4 battery. Engine starting and deep cycle incorporate the same cells.

Yes, I read the peak discharge - but that still does not make it suitable as a starter battery. If it was why does the maker not quote CCA which is the key measure for start batteries.

Can you point to exactly where and for which battery) it says recommended for engine start?

I know the cells of lithium are the same and and they are not described as deep cycle, but their defining characteristic is that they are superior in applications where deep discharge and rapid recharge are advantageous and superior to deep cycle LA. However this is not a requirement for start batteries.

As I said before rather than banging on about the benefits of lithium perhaps you should start from the requirements of the application and then choose the product that best meets this. You would then not come up with lithium for engine start, but find just as everybody else does that FLAs with high CCA such as the Numax the OP will probably go for are suitable. However if you want longer life (at greater cost) then the latest "stop start" AGMs are a good choice. If you want potentially even longer life and smaller size/weight then the dedicated high power AGMs do the job (at greater cost). All of these are a fraction of the cost of lithium and can be fitted into existing 12 or 24v boat systems without any modifications.

 

[geem]

Numax are a good choice, i've used many of them over the years, with no problems. My current boat came with 4 x Numax for the domestic bank and a pair of 105Ah (740CCA) to start a pair of 7 litre diesels, which they do at the touch of a button.

CCA varies between models of the same Ah, for instance, one 105Ah model is 740CCA and another is 800CCA

The CXV24MF at 630CCA would be a good choice, IMO.

I can get xv27mf or xv23mf. 570 or 720CCA. Will go for the bigger ones as they just fit

 

[PaulRainbow]

A different scenario entirely. Those are packaged battery packs bought and then installed. We are discussing making a pack. A different skill set.

Hmm, perhaps i should have asked you for some advice before carrying out the installation, although the customer did want a reliable and safe system.

 

[Zing]

Apples and Oranges .... me 'ol fruit .......

Now then my little plum dumpling, I disagree with that. I'd say a better analogy was crab apple vs bramley apple. i.e. it's all about scale. little engine, little battery. Big engine, big one. My 1100cc motorbike has a ridiculously small thing to start it. 1kg maybe. Hold it in the palm of your hand. You'd need a much, much bigger one to start a 4 or 6ltr high compression diesel. That 40Ah Winston would murder it.

 

[Zing]

Yes, I read the peak discharge - but that still does not make it suitable as a starter battery. If it was why does the maker not quote CCA which is the key measure for start batteries.

Can you point to exactly where and for which battery) it says recommended for engine start?

I know the cells of lithium are the same and and they are not described as deep cycle, but their defining characteristic is that they are superior in applications where deep discharge and rapid recharge are advantageous and superior to deep cycle LA. However this is not a requirement for start batteries.

As I said before rather than banging on about the benefits of lithium perhaps you should start from the requirements of the application and then choose the product that best meets this. You would then not come up with lithium for engine start, but find just as everybody else does that FLAs with high CCA such as the Numax the OP will probably go for are suitable. However if you want longer life (at greater cost) then the latest "stop start" AGMs are a good choice. If you want potentially even longer life and smaller size/weight then the dedicated high power AGMs do the job (at greater cost). All of these are a fraction of the cost of lithium and can be fitted into existing 12 or 24v boat systems without any modifications.

Of course I can, but I suggest you learn first how to use Google search, so you don't trouble strangers to look up information for you. The syntax I use, in the Google search window, which you can copy and modify for similar searches is:
"starter battery" site: https://shop.gw.eu/

You will find it throws up a number of pages of recommendations and information about lithium starter batteries.

The one I had in mind was:
WINSTON Lithium Battery 12V/40Ah (WB-LP12V40Ah) | shop.GWL.eu

As you can see they suggest it is suitable as a start battery.

Note this battery has zero BMS and should therefore they recommend it be used with care to monitor manually the correct charge voltages. It's not hard to do.

Note also this supplier is the leading retailer of LiFe batteries in Europe, so please don't be as fast to diminish their advice as you are to discredit me.

AGM batteries are fine. I don't disagree and as you mentioned earlier, the Odyssey is a particularly good battery. It along with sister brands Hawker Genesis and Cyclon are the best you can buy if you want lead and I don't blame you for that. People are conservative and reluctant to change, so good luck with your choice.

 

[Zing]

With all due respect. You have a lot to learn about using lithium batteries safely.
I am actually working on a lithium project. Liquid cooling them for high ambient operation. I do know a thing or two about lithium. Everything I suggested you need is common knowledge amongst those experienced with this technology. The internet is full of people telling you you don't need stuff. It's also full of tales of woe where installation like the one you are suggesting went horribly wrong.
Solar regulators don't necessarily fail dead. They can lose their control and charge at full solar output. You need to do some research on lithium before you start lecturing those that know how to do it safely. You are a good example of why insurance companies insist on proffessional installation of lithium batteries

When someone starts 'with all due respect' you know they are about to say something disrespectful and you didn't disappoint.

You, just like PaulRainbow are misjudging me and doing so without any proper evidence or wnquiry. it's rather a poor show. I do actually know quite a bit about lithium battery safely and if you had taken the time to discuss rather than spout off then you may have understood better. Maybe even have learnt something. Is that possible?

I have built and installed four boat house battery packs from bare bones. i.e. from cells and BMS circuit boards and ancilliary components. I have also helped design the installation in three other boats of fellow cruisers, who are all extremely happy with their installations. I have lived with lithium batteries in my own boat for 12 years now. I was one of the very first adopters of this technology. I have had various BMS systems for years and have similarly operated for years with no BMS system, so understand well the difference. I have seen batteries deteriorate and get replaced. You on the other hand have never owned one, never installed one, never designed a system. You have indeed worked on a cooling system for a specialist niche of battery. That however I'm afraid does not qualify as knowledge or experience of running and installing and designing battery systems, which is the subject at hand. Cooling is a specialist and different skill all of its own and I would be happy to seek your advice on that subject should it be necessary. So given your little experience and knowlege, what makes you so sure you are able to judge and disparage my comments as you have done?

Sure solar regulators fail as can all charge sources in an open voltage situation. just as they can fail dead, but surely you don't think that would be and is easily planned for? What happens when it fails with a lead battery? It gets warm and eventually it dies. That's because you don't oversize the charge source so that it totally overloads the battery. If you did the lead battery would boil, expel hydrogen gas and possibly explode. With lithium it's exactly the same, well safer actually. No explosions. But only if sized correctly, which of course one will do. The overcharging just produces a warm and distorted and failed battery. No big bloody deal. Of course I'm not suggesting you connect it to a 30Kw array and burn the boat down. Give a man some credit for heaven's sake!!

You know nothing about the safety of my installations, so why should you imply that I am an example of why boats burn down and trouble insurance companies is completely unfounded, with zero evidence or justification. I assure you I am far more interested in safety than any insurance company and my installations are of professional standard. I'd be happy to show you around some day if you ever got off your high horse.

 

[Tranona]

Of course I can, but I suggest you learn first how to use Google search, so you don't trouble strangers to look up information for you. The syntax I use, in the Google search window, which you can copy and modify for similar searches is:
"starter battery" site: https://shop.gw.eu/

You will find it throws up a number of pages of recommendations and information about lithium starter batteries.

The one I had in mind was:
WINSTON Lithium Battery 12V/40Ah (WB-LP12V40Ah) | shop.GWL.eu

As you can see they suggest it is suitable as a start battery.

Note this battery has zero BMS and should therefore they recommend it be used with care to monitor manually the correct charge voltages. It's not hard to do.

Note also this supplier is the leading retailer of LiFe batteries in Europe, so please don't be as fast to diminish their advice as you are to discredit me.

AGM batteries are fine. I don't disagree and as you mentioned earlier, the Odyssey is a particularly good battery. It along with sister brands Hawker Genesis and Cyclon are the best you can buy if you want lead and I don't blame you for that. People are conservative and reluctant to change, so good luck with your choice.

That is not the one you initially linked to.

It does not "recommend", let alone say it is specifically for engine start - just says it is possible to use, but with reservations about how you manage it and requires additional equipment to do that. Also in the context of this thread is of no use to the OP as it cannot be used in series to give the 24v he needs to start his engine.

You are right, people are conservative - but then the requirements for starting a diesel on a boat are pretty basic and easily met by lead acid in all its forms. I fitted my first Red Flash in the mid 1990s (along with a Lifeline AGM house battery) so not one who is reluctant to change. Because they last so long (just replaced the one in my car after 19 years) re- assessing the requirements does not come often. My view at this point in time having just made my choices for my latest boat is that lithium does not offer any benefits over what I chose for my pattern of usage - but of course for others whose requirements are different may well be able to make fuller use of the properties.

 

[Zing]

Hmm, perhaps i should have asked you for some advice before carrying out the installation, although the customer did want a reliable and safe system.

It's a nice installation Paul. But it is not the design of a battery system such as we are discussing. It is a pre-packaged Victron battery, complete with a BMS. What I have built a number of times is the installation you have bought from Victron, but at probably a sixth or less of the cost pro-rata to capacity. I'm sorry, but whilst it is nice and tidy and has all the ancilliary components you might want, it is something totally different. It is a systems integration installation. If you actually do lower yourself to ask for advice on the subject of lithium cell installations I would be more than happy to provide that advice.

 

[Zing]

That is not the one you initially linked to.

It does not "recommend", let alone say it is specifically for engine start - just says it is possible to use, but with reservations about how you manage it and requires additional equipment to do that. Also in the context of this thread is of no use to the OP as it cannot be used in series to give the 24v he needs to start his engine.

It is actually what I linked to. Specifically it is the one linked to in the link in my last post to you as being recommended as being suitable for larger engine starting installations.

I said to be absolutely precise to the point of cutting with a knife blade: "they suggest it is suitable as a start battery". Isn't that a recommendation or are we being a little pedantic maybe?

 

[geem]

When someone starts 'with all due respect' you know they are about to say something disrespectful and you didn't disappoint.

You, just like PaulRainbow are misjudging me and doing so without any proper evidence or wnquiry. it's rather a poor show. I do actually know quite a bit about lithium battery safely and if you had taken the time to discuss rather than spout off then you may have understood better. Maybe even have learnt something. Is that possible?

I have built and installed four boat house battery packs from bare bones. i.e. from cells and BMS circuit boards and ancilliary components. I have also helped design the installation in three other boats of fellow cruisers, who are all extremely happy with their installations. I have lived with lithium batteries in my own boat for 12 years now. I was one of the very first adopters of this technology. I have had various BMS systems for years and have similarly operated for years with no BMS system, so understand well the difference. I have seen batteries deteriorate and get replaced. You on the other hand have never owned one, never installed one, never designed a system. You have indeed worked on a cooling system for a specialist niche of battery. That however I'm afraid does not qualify as knowledge or experience of running and installing and designing battery systems, which is the subject at hand. Cooling is a specialist and different skill all of its own and I would be happy to seek your advice on that subject should it be necessary. So given your little experience and knowlege, what makes you so sure you are able to judge and disparage my comments as you have done?

Sure solar regulators fail as can all charge sources in an open voltage situation. just as they can fail dead, but surely you don't think that would be and is easily planned for? What happens when it fails with a lead battery? It gets warm and eventually it dies. That's because you don't oversize the charge source so that it totally overloads the battery. If you did the lead battery would boil, expel hydrogen gas and possibly explode. With lithium it's exactly the same, well safer actually. No explosions. But only if sized correctly, which of course one will do. The overcharging just produces a warm and distorted and failed battery. No big bloody deal. Of course I'm not suggesting you connect it to a 30Kw array and burn the boat down. Give a man some credit for heaven's sake!!

You know nothing about the safety of my installations, so why should you imply that I am an example of why boats burn down and trouble insurance companies is completely unfounded, with zero evidence or justification. I assure you I am far more interested in safety than any insurance company and my installations are of professional standard. I'd be happy to show you around some day if you ever got off your high horse.

Wow!
For somebody who knows so much about lithium but know nothing about class T fuses. Thinks Lithium is a great choice for starter batteries on a 4.4 litre diesel because he has one on a motorbike. Thinks its good practise to run lithium without a BMS. Happy to charge lithium with an alternator but no regulator control. Assumes he knows more than the professionals I have been working with as part of large British company who incidentally are running several lithiium projects with major car manufacturers.
I never suggested your boat will burn down. That's your idea.
Proffessional standard. Prove it. Show me you understand the safety side of the installation. So far your posts have not suggested thats the case.

 

[William_H]

Correction please .... Lithium cells Max voltage range from 2.5V up to 4.35V depending on 'chemistry'. The LiFe / LiFePo are usually 3.65V max .... per cell.

Thanks Nigel yes I sort of felt my quoting max voltage for lithium (in general) was risky. As you say it all depends but it is critical. ol'will

 

[Zing]

Wow!
For somebody who knows so much about lithium but know nothing about class T fuses. Thinks Lithium is a great choice for starter batteries on a 4.4 litre diesel because he has one on a motorbike. Thinks its good practise to run lithium without a BMS. Happy to charge lithium with an alternator but no regulator control. Assumes he knows more than the professionals I have been working with as part of large British company who incidentally are running several lithiium projects with major car manufacturers.
I never suggested your boat will burn down. That's your idea.
Proffessional standard. Prove it. Show me you understand the safety side of the installation. So far your posts have not suggested thats the case.

I know enough about class T fuses. Nothing you say I know! You have zero evidence. It's not like they are that difficult. There are plenty of alternatives equally as good. I actually use NH type and you will find in my posts that I do recognise the importance of fusing. So what point are you making? Niggling and nit picking more like. Heavens knows you must be bored.

I didn't say lithium were even a great choice. I said they were something to consider. I didn't say that because they worked on a motorbike, I just mentioned that when I was challenged that lithium batteries couldn't start engines and were not suitable for starting engines, I said that even a tiny one will start a moderate sized motorbike engine and are suitable because they are approved by major manufacturers. You are misrepresenting and misquoting me here.

I don't assume I know more than professionals, but I know what I know and there were no professionals in this tech when I started, so I became my own professional. Besides, I professionals get it wrong all the time, so in general professionals need questioning. Or are they beyond being questioned because they have a badge and medal?

Yes you did suggest my boat would be at risk of burning down, because that is the only risk insurers would be concerned with in my boat, so you did imply it if not say it in so many words.

By the way, you should understand that there is almost no risk of LiFePo4 catching fire and absolutely so with the type I use, so that you made the above comments on insurance risk suggest a sad lack of knowledge and understanding.