New battery setup

[Neeves]

I checked, based on lustyd's comments

Noting we have a 10% sales tax - I can buy, on special, a 200amp/hr Lithium for Stg350 weighing in at 23kg & from a 4x4 supplier Home Page - Adventure Kings . 10 years ago we replaced our 2 x 200amp/hr LAs - I could barely lift one of them. The 200amp/hr Lithium 'seems' physically smaller - I have not measured them and I have no idea of the quality of the Lithium. I do note that this battery in common with other Lithium batteries from the same source has an internal BMS which is undesirable according to the members here.

Jonathan

My post and my edit adding the link and pointing out the internal BMS crossed with that of Refueler.

 

[Refueler]

No idea what you mean by not cost effective, for £369 you can get a 105Ah lithium that has more usable capacity than your current two 60Ah batteries and is rated for 7 times the cycles. The difference being that your lead is almost guarateed to be totally dead after 500 cycles whereas the lithium will likely still have 80% original capacity after 3500.

mmmmmmm you sure about that ?

All Li formats regardless are not recc'd to go below 20% charged .... so your 105 is good for maximum 84 A/hrs

So 369 quid for basically 84 A/hrs ... ???????

I can buy at least 4 Lead Acid 80 A/hr batts for that .... giving me a conservative 60% end of use charge level of useable 128 A/hrs power ...

The only advantage I can see - is the flatter voltage gradient of the Li ....

Cycles ? How many cycles do you think car batts go through ... average boat batterys ? Cycles are based on full discharge to safe level - then recharged. Lead Acids are commonly quoted at ~ 500 cycles - but that is a very low estimate if battery is maintained reasonably ...

Li degrade from the very first use - actually all batts do .... but have no recovery capability. What kills Li - is Internal Resistance increases as batt is used .. or poorly stored. Lead Acid can be partially restored when in early stage of decline (once allowed to degrade further then its not recoverable).

Lets put it in street terms ... Lead Acid is the 'Idiots solution' ... Li needs setup and use according to strict rules.

Don't get me wrong ... I am not against Li .. far from it. In fact because I shall be racing my C38 ... I am considering all ways to lighten her down ... (done the toothbrush handles already !) ... but for most boaters ... KISS .....

 

[lustyd]

you sure about that ?

Yes. Yes I am. While lead can go to 50% it's far from recommended or good for them, and the lower voltage can cause havoc with other systems.
Yes, you can buy 4, but you'll need to do it 7 times to match the lifespan. We're not talking starter batteries we're talking house batteries. You're right, due to the safe discharge the lead will cycle considerably more times for the same usage, so will probably die even faster still.

We've not seen many lithiums treated badly in boats yet. Yes, there are a lot of rules but they're not all that hard to follow with modern chargers. You're ignoring the great many rules people have to follow with lead. I'd argue lead isn't an idiot's solution as it's too easy to kill them by over discharging. My BMS will prevent me killing the lithium, will your lead? No, and we've seen countless threads of overdischarged and overcharged cooked leads on here so let's not pretend they are care free and simple.

 

[Tranona]

It would help if some people read post#1 again and applied their thoughts to what the OP is trying to achieve. What he has currently is quite normal for a weekend/holiday use 27' sailing boat. The changes he wants to make over what is currently there (assumption?) of lights and basic instruments and VHF are to add a chart plotter and a fridge and ideally split the banks and add a means of starting the engine from the house bank. The chart plotter adds little to consumption, but the fridge will.

The existing power generation of a 35A alternator and 50W solar plus occasional mains with a 5A charger is probably adequate but extra battery capacity will be needed to run the fridge. The starting point is to upgrade the switching and charging system as in post#14 (or using a switch cluster). The constraint for increasing capacity is limited space in the existing battery compartment to add another 100ah battery to the house bank - hence the question of going lithium. However this is a very expensive route and the properties that justify the higher price (fast charging, extended cycles etc) are of little value as he can't take advantage of them.

The simplest route is to solve the basic problem - running the new fridge. Assuming a split switching/charging system has been added the easiest way is to add a dedicated 100ah battery ideally located close to the fridge and charged by a B2B from the start battery. A 2 output 20A mains charger to the existing house and the new fridge battery would be useful, as would increasing solar particularly to top up when boat is not being used. This will enable him to start with fully charged batteries and get maximum use out of the capacity he has.

Just an observation on life cycles. Extended cycles is indeed a big selling point for lithium - but who needs them? a lot is talked about cost per ah over time - but the time required to benefit for a "weekend" type sailor is literally a lifetime! 10 weekends and 2*2 week cruises a season is 50 cycles a year assuming each day on board you use and recharge the full usable capacity of your house bank. Typical SLA (leisure batteries) 50% discharge cycles are 4-500, so a life of up to 10 years. AGMs, approx 50% more so a life of up to 15 years. This borne out in practice from the few people who actually keep their boats that long. Lithium 2000+ - how many weekend sailors have 40 year careers with the same boat?

Of course if you are a heavy user such as liveaboards (almost inevitably bigger boat than a 27') and want to use a lot of electrical gear - big fridges, water makers, microwaves, computers, fans, TVs and so on) the batteries are central to your lifestyle. 365 cycles a year kills basic cheap LA, but there are ways of enhancing life such as heavy duty deep cycle, AGMs and increasing reserve capacity which liveaboards have been doing for years. It is this pattern of usage where Lithium is most valuable and the high initial cost can be justified. Quite ridiculous though at the other end of the usage scale like the OP (and many on here) with modest boats and modest electrical requirements.

 

[Refueler]

It would help if some people read post#1 again and applied their thoughts to what the OP is trying to achieve. What he has currently is quite normal for a weekend/holiday use 27' sailing boat. The changes he wants to make over what is currently there (assumption?) of lights and basic instruments and VHF are to add a chart plotter and a fridge and ideally split the banks and add a means of starting the engine from the house bank. The chart plotter adds little to consumption, but the fridge will.

The existing power generation of a 35A alternator and 50W solar plus occasional mains with a 5A charger is probably adequate but extra battery capacity will be needed to run the fridge. The starting point is to upgrade the switching and charging system as in post#14 (or using a switch cluster). The constraint for increasing capacity is limited space in the existing battery compartment to add another 100ah battery to the house bank - hence the question of going lithium. However this is a very expensive route and the properties that justify the higher price (fast charging, extended cycles etc) are of little value as he can't take advantage of them.

The simplest route is to solve the basic problem - running the new fridge. Assuming a split switching/charging system has been added the easiest way is to add a dedicated 100ah battery ideally located close to the fridge and charged by a B2B from the start battery. A 2 output 20A mains charger to the existing house and the new fridge battery would be useful, as would increasing solar particularly to top up when boat is not being used. This will enable him to start with fully charged batteries and get maximum use out of the capacity he has.

Just an observation on life cycles. Extended cycles is indeed a big selling point for lithium - but who needs them? a lot is talked about cost per ah over time - but the time required to benefit for a "weekend" type sailor is literally a lifetime! 10 weekends and 2*2 week cruises a season is 50 cycles a year assuming each day on board you use and recharge the full usable capacity of your house bank. Typical SLA (leisure batteries) 50% discharge cycles are 4-500, so a life of up to 10 years. AGMs, approx 50% more so a life of up to 15 years. This borne out in practice from the few people who actually keep their boats that long. Lithium 2000+ - how many weekend sailors have 40 year careers with the same boat?

Of course if you are a heavy user such as liveaboards (almost inevitably bigger boat than a 27') and want to use a lot of electrical gear - big fridges, water makers, microwaves, computers, fans, TVs and so on) the batteries are central to your lifestyle. 365 cycles a year kills basic cheap LA, but there are ways of enhancing life such as heavy duty deep cycle, AGMs and increasing reserve capacity which liveaboards have been doing for years. It is this pattern of usage where Lithium is most valuable and the high initial cost can be justified. Quite ridiculous though at the other end of the usage scale like the OP (and many on here) with modest boats and modest electrical requirements.

Totally agree .... and is why I posted earlier about threads hijacked by those who require extensive capacity.

 

[B27]

I checked, based on lustyd's comments

Noting we have a 10% sales tax - I can buy, on special, a 200amp/hr Lithium for Stg350 weighing in at 23kg & from a 4x4 supplier Home Page - Adventure Kings . 10 years ago we replaced our 2 x 200amp/hr LAs - I could barely lift one of them. The 200amp/hr Lithium 'seems' physically smaller - I have not measured them and I have no idea of the quality of the Lithium. I do note that this battery in common with other Lithium batteries from the same source has an internal BMS which is undesirable according to the members here.

Jonathan

My post and my edit adding the link and pointing out the internal BMS crossed with that of Refueler.

There is no doubt that Lifepo4 batteries are good and getting cheaper.
The only question really is how many people with modest needs don't see any benefit that they don't get from cheaper lead-acid.
One issue in some cases will be that the BMS may 'protect' the battery from your attempt to start the engine with it.
Which will probably also be a 'here endeth the warranty' event.

 

[Stemar]

, for £369 you can get a 105Ah lithium that has more usable capacity than your current two 60Ah batteries

Yes, but is it a drop in replacement, or will I have to buy a load more bits? BMS, B2B charger/ new alternator(s), etc. It's complicated by the fact that I have two engines, with two alternators.

Don't get me wrong, I know the ideal setup for Jazzcat would be 200AH of LIFePO batteries plus all the toys to keep them happy, but Management is quite clear that the budget won't run to that

 

[Refueler]

Yes. Yes I am. While lead can go to 50% it's far from recommended or good for them, and the lower voltage can cause havoc with other systems.
Yes, you can buy 4, but you'll need to do it 7 times to match the lifespan. We're not talking starter batteries we're talking house batteries. You're right, due to the safe discharge the lead will cycle considerably more times for the same usage, so will probably die even faster still.

We've not seen many lithiums treated badly in boats yet. Yes, there are a lot of rules but they're not all that hard to follow with modern chargers. You're ignoring the great many rules people have to follow with lead. I'd argue lead isn't an idiot's solution as it's too easy to kill them by over discharging. My BMS will prevent me killing the lithium, will your lead? No, and we've seen countless threads of overdischarged and overcharged cooked leads on here so let's not pretend they are care free and simple.

Sorry - but use and observation does not allow me to agree with your mathematics. It appears that you are using Li sellers data to justify your stance.
For many years I was not only boating - but caravanning as well ... Boating of course continues on ....

Couple weeks ago - I posted about hard to find hatch stays of a particular older design I wanted ... I visited not only chandlers - but also respected RV dealers along the south coast. Having been away from the caravan scene for a while - I was interested in latest trends.

Can I surprise you - Li was way down the list - which was a total surprise ... the staff smiled and stated clearly that it was questionable as the real advantage and they regarded it as a 'fashion trend' ....

OK - lets look at your post ...

Yes, you can buy 4, but you'll need to do it 7 times to match the lifespan

Sorry but that's only valid for those who are daft with their LA batts. Second its also easy to destroy a Li cell .... sorry Zero pts there.

You're right, due to the safe discharge the lead will cycle considerably more times for the same usage, so will probably die even faster still.

How do you arrive at that ? As long as the LA is maintained reasonably - the life is significant and many people have LA for 7 .. 8 ... 10yrs or more. I never made any comment that could lead to you saying "I'm right .... leading to etc", 1 cycle = from max recc'd discharge charged to full and then discharged back to max recc'd discvharged. Cycles are also accounted in % ... and %'s are accumulated to create full cycles. Your comment implies that a recharge from reasonable level is 1 full cycle .... it is not. It is a PART cycle.

We've not seen many lithiums treated badly in boats yet.

Mainly I suggest because they are not as widespread in use as some would like to imply. Regardless of boats value - boaters tend to be miserly with their wallets ... I suggest Lead Acid will be majority still for many years to come.

You're ignoring the great many rules people have to follow with lead. I'd argue lead isn't an idiot's solution as it's too easy to kill them by over discharging. My BMS will prevent me killing the lithium, will your lead? No, and we've seen countless threads of overdischarged and overcharged cooked leads on here so let's not pretend they are care free and simple.

The comment about being 'Idiots' batterys and simple was based on the ease of purchase / replacement etc. The simple fact is that Lead Acid is still more convenient ... plenty of sales points for them ...
As to BMS .... that is really a poor factor as a large number of Lead Acid users do have BMS and monitor systems .... I don't - but that's because its rare for me to at such low point to need such. But my over imbibed state other night has caused me to consider a Voltage Protection unit.

How many boats out there with Lead Acid vs Li ?? Ignoring the ratio between the two and claiming about damaged Lead Acid as reason to change is frankly a non starter ...

The OP does not have demand that warrants high cost expenditure ... as others have said - consideration of increasing his present capacity ... increasing the solar charge capability ... getting a high rate mains charger .... all well within sensible economic budget ...

 

[PaulRainbow]

Yes. Yes I am. While lead can go to 50% it's far from recommended or good for them, and the lower voltage can cause havoc with other systems.

50% is just over 12V, other than possibly a fridge with inadequate wiring, i can't think of much that would be affected. Causing havoc is nonsense.

We've not seen many lithiums treated badly in boats yet. Yes, there are a lot of rules but they're not all that hard to follow with modern chargers. You're ignoring the great many rules people have to follow with lead. I'd argue lead isn't an idiot's solution as it's too easy to kill them by over discharging. My BMS will prevent me killing the lithium, will your lead? No, and we've seen countless threads of overdischarged and overcharged cooked leads on here so let's not pretend they are care free and simple.

Of course, Lithiums don't have to follow any rules, do they ? Must not, overcharge, undercharge, float charge, leave fully charged for long periods, get too hot, get too cold, etc etc etc. You have a BMS to manage some of those rules, but have failed to install any protection against over heating or cold, amongst other things.

Lead acid also don't like under or over charging, a decent charging regime takes care of most of that, without spending a fortune. Something along the lines of a Victron Battery Protect stops over discharge.

Lead acid and Lithium both have rules and if measures are taken to follow those rules, both can last a long time. You are trying to compare a Lithium installation with all sorts of external battery protection with a lead acid installation that has no protection and is abused, not exactly a fair comparison.

 

[fredrussell]

That’s just the thing though, it no longer is more expensive per usable Ah.

That has been my finding of late. I’m looking for a replacement for the dying lead acid leisure battery in my VW T5 camper.

I had the choice of cheap 100 a/h LA at £90 or so, budget AGM at £140 or so, or 50a/h lithium for £160. The last two cheap LA I bought lasted 2 years in a completely pampered environment (marina boat) - not so for the two 2nd hand true deep cycle batts I bought to replace them (cheers Paul), these are rock solid but come at quite a cost if bought new. So for me the choice was between AGM and Lithium. Price was close enough so I chose the latter. Drop in replacement as LB on my van charged solely from 160a/h solar on van roof.

 

[lustyd]

Yes, but is it a drop in replacement, or will I have to buy a load more bits? BMS, B2B charger/ new alternator(s), etc.

Drop in. You could get away with just the battery and a fuse if you wanted to. The BMS will stop charging when full so as long as the house battery is never connected without the lead the alternator would be fine.

 

[lustyd]

but the time required to benefit for a "weekend" type sailor is literally a lifetime!

I disagree. I've replaced the lead batteries on both of my boats and the number of threads here about batteries dying suggests that's far from rare.

 

[Neeves]

There is no doubt that Lifepo4 batteries are good and getting cheaper.
The only question really is how many people with modest needs don't see any benefit that they don't get from cheaper lead-acid.
One issue in some cases will be that the BMS may 'protect' the battery from your attempt to start the engine with it.
Which will probably also be a 'here endeth the warranty' event.

I don't know the OP. However he has looked at Lithium and in his opening post seemed to have accepted the price differential. As I don't know the OP I don't know and would never suggest he has modest needs. He may find that Lithium is lighter and smaller than an equivalent, in amp terms, of a LA battery - and this is important to him - but I would not guess. He might like the idea that he can use much of the energy stored in his Lithium battery, whereas he can only use 50% of the energy in his LA - I don't know.

What I find here (in Oz), which is totally irrelevant to the OP, is that the 'caravan/4x4/off grid' market has a very well developed Lithium segment and you can visit one of a number of distributors and they offer a complete off the shelf package (made up of a variety of components). This same option might be available in Europe, I don't know. Its not difficult - and if you have read the threads here you would visit any and all of these distributors with some background - as Geem et al have shown if you have a modicum of intelligence - its not rocket science.

All we can do is present to the OP options - if the OP adds more background our presentations might change.

We had our 38' cat for 25 years and replaced the house bank, 2 x 200amp hrs and the single engine start battery 60 amp hours once, each, different timings. We had a 1,2 both battery switch but never used the house bank to start the engines (in all that time). Our cat was 'pre Lithium'.

Today I would not think twice - we'ed have lithium - but we did spend 3 months of the year 'off grid' so not quite the same as the OP. But if the OP wants to spend more than a week off grid - he might value LA .... less - again I don't know and he might be of modest needs - but ambitious. In the grand scheme of things Lithium is not that expensive - a case of malt? 2 cases or malt??? - which is more important - less restricted access to power or....malt.

Jonathan

 

[lustyd]

50% is just over 12V, other than possibly a fridge with inadequate wiring, i can't think of much that would be affected. Causing havoc is nonsense.

But when the fridge decides to kick in the voltage drops and the plotters and AP alarm, often knocking the AP back to manual steering without warning. This was the case with my Raymarine and now my B&G. Hardly nonsense.

 

[PaulRainbow]

But when the fridge decides to kick in the voltage drops and the plotters and AP alarm, often knocking the AP back to manual steering without warning. This was the case with my Raymarine and now my B&G. Hardly nonsense.

Obviously a poor installation, with inadequate monitoring and safety measures.

Easy to cure, ensure the fridge wiring is the correct size and fit a battery saver so the fridge cannot work below a certain voltage. A decent battery monitor with a low voltage alarm also helps.

 

[lustyd]

Obviously a poor installation, with inadequate monitoring and safety measures.

Easy to cure, ensure the fridge wiring is the correct size and fit a battery saver so the fridge cannot work below a certain voltage. A decent battery monitor with a low voltage alarm also helps.

It’s not a poor installation it’s a flat battery! Yes we can fit all kinds of bells and whistles, but I thought the argument for lead was not doing so? That’s the thrust of the thread certainly.
Personally I went for more capacity

 

[PaulRainbow]

It’s not a poor installation it’s a flat battery! Yes we can fit all kinds of bells and whistles, but I thought the argument for lead was not doing so? That’s the thrust of the thread certainly.
Personally I went for more capacity

Of course it's a poor installation, if it allows the domestic bank to get so low, without warning, that the fridge causes low voltage problems with electronics.

Again, you are trying to compare a Lithium installation, with BMS etc to a totally unprotected LA installation, a totally meaningless comparison.

 

[Refueler]

 

[lustyd]

Of course it's a poor installation, if it allows the domestic bank to get so low, without warning, that the fridge causes low voltage problems with electronics.

Again, you are trying to compare a Lithium installation, with BMS etc to a totally unprotected LA installation, a totally meaningless comparison.

Who mentioned without warning? I simply said that the lithium will keep on going in that circumstance. You've imagined the rest.

To be clear, I've not been arguing against lead, I've been arguing for lithium. The lead crowd seem to be arguing against lithium will all kinds of odd arguments, most of which are not true and they have no experience of.

 

[PaulRainbow]

Who mentioned without warning? I simply said that the lithium will keep on going in that circumstance. You've imagined the rest.

To be clear, I've not been arguing against lead, I've been arguing for lithium. The lead crowd seem to be arguing against lithium will all kinds of odd arguments, most of which are not true and they have no experience of.

You said :
"But when the fridge decides to kick in the voltage drops and the plotters and AP alarm, often knocking the AP back to manual steering without warning. This was the case with my Raymarine and now my B&G. Hardly nonsense."

No mention of "Lithium keep going"

LA would have kept going if you added more capacity, which is what you did with the Lithium installation. Also, if properly monitored and suitable battery protection fitted, you would not have let the batteries get so flat that the electronics would suffer low voltage issues. Again, you have added that protection with your Lithium BMS.

So again, you are not making fair comparisons. Remove the BMS, see how long your Lithium battery lasts.