LiFeP04 Charging Question

[geem]

A reason amongst many to swap to Lithium is that you can lighten your battery bank (by crudely) 50%. And a 200amp Lead battery is seriously heavy. If saving weight is a focus then using smaller chain offers greater savings in weight, but like (and this was a point) Lithium there are hidden costs.

My view is - costs have nothing to do with me, I don't know the size of your wallet. I just like to mention all aspects, not just highlight the advantages - and leave you (and your partner) to sort out the financial implications.

I'm not flush but am able to afford Lithium as a 'big boys' toy - maybe I'm lucky (I don't know as I don't have male playmates). Actually I know I'm lucky But I do know how much all the bits cost. I have offset the costs as we have wired my toy to our galley (or in reality) to the kitchen and roughly we cook for free - except after 2 or 3 days of overcast skies. Today we had breakfast and dinner - cooked for free, we were out for lunch (at a show within which was a big Lithium display).

This has made me think - considering the numbers of people who underutilise the Lithium bank on their yacht, the excess could be 'bought' by the marina and passed into the grid. But maybe power is cheaper, in say, the UK and not using and getting a return on the investment is not worth the effort.

Now if all these floating, under-utilised, micro power stations could be a source of income or credits - the equations all change.

and CTVA

There is nothing stopping you having a lead house bank (which also starts the engine etc) as well as a lithium house bank. If your 'old' Lead is good enough to start the engine, replacing the geriatric one - why not have 2 house banks?

I am a parsimonious Scot.

Jonathan

We cook off our lithium. Ran the generator yesterday for the first time in 3 weeks. Partly because I needed to run it. Partly because we had a rainy day. It was on for 30mins. We don't use much in the way of propane. We are on the same bottle from last summer. We also make all our drinking water from the lithium and our hot water. Pretty impressive performance from lithium and solar

 

[RunAgroundHard]

It's so cheap to build lithium now, it comparable with lead. ...

... But. most people, who post here, are not buying new yachts. Their Lead batteries may need replacing but all the bits and prieces that they have to charge, manage and use the Lead is now no longer needed - resale value - peanuts.

I am an old boat owner. Over the years I have renovated and upgraded the boat, a mix of professional and DIY. I have never touched the charging system beyond replacing batteries. The batteries are now needing replacement again, 4 x 6V T105s in series for a 24V system, around £850, maybe a bit lower if I shop around. I have ancient twin alternators and a split diode charge system. For me, it is a no brainer, remove the lot and fit a modern alternator, regulator and lithium, with solar. I did wonder about changing the charging system and making it lithium ready, but why bother now that lithium has arrived. It will be a bit pricy, early days yet for me. I never went for VSRs as the system worked for the type of sailing I am doing. However, as retirement looms, I will be sailing further for longer, I think the need will be there for lithium compared to lead acid. The resale value of my current stuff is scrap value. However, there might be a market for my ancient 24V alternators, regulators, noise suppressors in the classic truck market; a niche, I would agree. However, the real value is not resale, but is on diesel costs and convenience when moving to lithium.

 

[ctva]

...
There is nothing stopping you having a lead house bank (which also starts the engine etc) as well as a lithium house bank. If your 'old' Lead is good enough to start the engine, replacing the geriatric one - why not have 2 house banks?

I am a parsimonious Scot.

Jonathan

Ah, one of us!

Good idea....

 

[Neeves]

Ah, one of us!

Good idea....

It is a good idea, but not mine. I claim no credit. But if it saves money, or uses a resource going to waste.....I'm a product of John Knox discipline

I think Geem did this. But I forgot the details. He is active in this thread and may correct me.

I think the big issue might be space (and, I hate to mention it, weight). How many have space for 2 hulking great extra batteries?

Jonathan

Geem hit that one on the head , see Post 45.

 

[geem]

It is a good idea, but not mine. I claim no credit. But if it saves money, or uses a resource going to waste.....I'm a product of John Knox discipline

I think Geem did this. But I forgot the details. He is active in this thread and may correct me.

I think the big issue might be space (and, I hate to mention it, weight). How many have space for 2 hulking great extra batteries?

Jonathan

I did have my old lead bank and the new house lithium for about 3 months. At that point, I realised it was a waste of time. I gave my 4 Trojans T105s to a farmer in Grenada. I then built and installed a second lithium battery. The remaining spare battery compartment space got converted to a locker for tools.

 

[Neeves]

I am an old boat owner.

However, the real value is not resale, but is on diesel costs and convenience when moving to lithium.

I think I read this correctly - you have the thoughts of a youth, 'Juventus veho Fortunas' and the yacht is traditional

Why are you going to save diesel? Convenience I do understand.

It does not matter if you use Lead or Lithium but the usage, your AP or your Breadmaker will use the same number, or amount, of amps. What you might find is that you use more amps, because its so convenient and because you can. If you use a 30 amp B2B it will need the engine running longer to charge the Lithium (because you use more, the induction hob) unless you have a big solar display.

Because our battery is small, 200amps and the solar display, also, small 2 x 150 watts, fixed for the midday sun, we bake bread schedule to the days when we have the 'best' sun - so I know our battery and solar display are too small (which was the motivation for the 'toy' to find out how useful it was or could become). None of this is helped as we run a 60l icebox at 4 degC 24/7 and juice fruit with a Kenwood juicer (and we would not do the latter on a yacht as the fruit would unlikely to be available and we would not have fridge room to store the juice.


We went to a big camping show today, the boat shows here are in 2-4 months time. Lots of companies promoting Lithium, lots of new companies (that I have never heard of) selling Lithium Batteries, nothing but batteries. I specifically asked about BMS - monitor BMS 'never heard of that sir', blue tooth 'why would you have blue tooth'.

Its a different world

At the same show there was a Lecture on crossing the Simpson Desert, only 1 week off grid, and another on one of the stock routes, 4 weeks off grid. Losing you battery would be as much a disaster as having your instruments failing mid-Atlantic or entering a marina.

Jonathan

 

[RunAgroundHard]

… Why are you going to save diesel? …

The diesel savings comes from the solar which I don't currently have, compared to current charging on engine. Also additional savings will cone from marina fees when I need to get to shore power. My charging system is old.

This will supplement my wind powered generator, which is an old AirX 400 (which needs bearings serviced).

 

[geem]

The diesel savings comes from the solar which I don't currently have, compared to current charging on engine. Also additional savings will cone from marina fees when I need to get to shore power. My charging system is old.

This will supplement my wind powered generator, which is an old AirX 400 (which needs bearings serviced).

For us there are savings. In our normal 9 month season as liveaboards would use the generator for about 100 hrs. Over the same period we have done 24hrs. Some of that was a routine run. A 8.5kg bottle of gas would last us 6 weeks prior to lithium as we now cook on an induction hob. About £300 a year saving on fuel for us. For cooking and generator use but we do have good sunshine here in the Caribean

 

[GHA]

The diesel savings comes from the solar which I don't currently have, compared to current charging on engine. Also additional savings will cone from marina fees when I need to get to shore power. My charging system is old.

This will supplement my wind powered generator, which is an old AirX 400 (which needs bearings serviced).

Even with solar and ignoring the costs, not *having* to run the engine or genny for hours and hours once a week or so to get lead acid up near full when there's not much sun or daylight hours makes such a difference. LiFePo4 will soak up everything you give in when the sun does come out unlike LA which is drip drip drip power going in towards full needing hours & hours of sun, & leave them not full you are killing them....
What a game changer LiFePo4 is living aboard full time!!

 

[Frankklose]

I have a 280ah Lithium and a 70ah lead starter battery,. The lithium is charged via the Renogy 40 A DC2DC and for land power with a Victron IP22 30A. For the Starter Battery I use the.old Sterling 20 A charger.
The Renogy DC2Dc draws 51 A. My alternator delivered only 50A and the remaining 1 A was drawn out of the start battery...not good...so I changed the alternator to a 75 A. That's works..
In future I will change the Renogy DC2DC for the new Victron 50A DC2DC. This one is adjustable in one A charging steps and has in addition a contact to stop charging and Bluetooth. I am very fed up with the Renogy. Low efficiency only one error light. Errors are clearing only by disconnecting input and output...I had the Renogy in the engine room installed, when the temperature reached 46 degrees the Renogy turned off, Now the Renogy was relocated into the locker and working. Since it was a intermittent fault it took a long time to find the reason. Therefore I will never ever install a charger without Bluetooth....I have the Renogy working for 3 years, it will change it this season for the new Victron.... I'm fed up with the Renogy....the Victron has an efficiency of 98% compared to 80% of the Renogy. The extra contact input on the Victron, I will use it with a thermostat connected to the alternator. When the alternator gets too hot the DC2DC will be turned off.

 

[Daverw]

We’ve just fitted the new Victron 50amp unit, works very well and so easy to set up

 

[lustyd]

We’ve just fitted the new Victron 50amp unit, works very well and so easy to set up

Do they run cooler than the old ones?

 

[Daverw]

When I run it after fitting it did not get very warm at all. With the reported higher efficiency it should not get as hot as others, although it was throttled back to 40amps for most of the running

 

[geem]

We went to a big camping show today, the boat shows here are in 2-4 months time. Lots of companies promoting Lithium, lots of new companies (that I have never heard of) selling Lithium Batteries, nothing but batteries. I specifically asked about BMS - monitor BMS 'never heard of that sir', blue tooth 'why would you have blue tooth'.

Its a different world

At the same show there was a Lecture on crossing the Simpson Desert, only 1 week off grid, and another on one of the stock routes, 4 weeks off grid. Losing you battery would be as much a disaster as having your instruments failing mid-Atlantic or entering a marina.

Jonathan

There are a number of lithium forums on the net. There are resident experts on those forum that know what they are talking about. They have a collective of excellent knowledge. What is consistent is the advise to buy good quality batteries. It rarely wavers. The message is consistent that you need Bluetooth.
Just because salesmen are pushing their inferior product doesn't make is right. If you life depends on making it across OZ in 4 weeks with a working battery, why would you take the risk?
Rod Collins, who was instrumental in writing the ABYC Lithium standard in the USA is of the opinion that manufacturers don't fit Bluetooth on cheap batteries so that the purchaser cannot see how poor the cells are. He suggests that fitting Bluetooth would cost the manufacturer about $2 per battery.

 

[Neeves]

There are a number of lithium forums on the net. There are resident experts on those forum that know what they are talking about. They have a collective of excellent knowledge. What is consistent is the advise to buy good quality batteries. It rarely wavers. The message is consistent that you need Bluetooth.
Just because salesmen are pushing their inferior product doesn't make is right. If you life depends on making it across OZ in 4 weeks with a working battery, why would you take the risk?
Rod Collins, who was instrumental in writing the ABYC Lithium standard in the USA is of the opinion that manufacturers don't fit Bluetooth on cheap batteries so that the purchaser cannot see how poor the cells are. He suggests that fitting Bluetooth would cost the manufacturer about $2 per battery.

Apologies,

I'm not advocating batteries with inadequate BMS - what I'm saying is there are a lot of cheap, poor BMS batteries being promoted in the market which may cause anguish with time.

If the risks that these batteries pose eventuate then we are going to hear of increasing numbers of LiFePo4 fires - and LiFePO4 will rapidly develop a bad name. The fires will be said to be caused by 'Lithium' not by an inadequate BMS.

My assessment is that the people promoting these batteries have no idea but they will be treated by the market place as professionals (as the market place has even less knowledge).

There may be a number of Lithium forums and there may be individuals with in depth expertise - but this is not being accessed by lots, most?, of the people who form the customer base.

I'm convinced, by you, but have not yet converted.

I will be going to 2 big boat shows mid year - it will be interesting to see how the marine industry is addressing the issues.

Jonathan

 

[geem]

Apologies,

I'm not advocating batteries with inadequate BMS - what I'm saying is there are a lot of cheap, poor BMS batteries being promoted in the market which may cause anguish with time.

If the risks that these batteries pose eventuate then we are going to hear of increasing numbers of LiFePo4 fires - and LiFePO4 will rapidly develop a bad name. The fires will be said to be caused by 'Lithium' not by an inadequate BMS.

My assessment is that the people promoting these batteries have no idea but they will be treated by the market place as professionals (as the market place has even less knowledge).

There may be a number of Lithium forums and there may be individuals with in depth expertise - but this is not being accessed by lots, most?, of the people who form the customer base.

I'm convinced, by you, but have not yet converted.

I will be going to 2 big boat shows mid year - it will be interesting to see how the marine industry is addressing the issues.

Jonathan

I don't think cheap batteries will likely cause fires. They still have a bms that should shutdown the battery if it goes outside acceptable parameters. I think the battery failure rate is likely to increase as poorly matched cells cause more and more battery shutdowns.
Fires in lifepo4 chemistry batteries seem pretty impossible to start. It may be possible with a faulty charger running full amps and a BMS that has failed closed circuit but from those that know about bms electronics, I understand that that scenario is very unlikely.

 

[NBs]

We’ve just fitted the new Victron 50amp unit, works very well and so easy to set up

 

[NBs]

I have SRNE 50A dc-dc / mppt charger, I think good, you can program yourself or use the ready lifepo4 program, handy when in the same solar regulator 700W max panels, the device also gets a blue tooth + app for your phone In addition, I put a wireless on/off relay to get the device off if I want to

Amazon.co.uk

 

[Neeves]

Reading the posts on this thread and others, Lithium is a popular subject (for some) maybe becoming more popular that another topic. The uptake, of Lithium, is quite significant - interesting numbers of people now contributing to the threads. Its not quite mundane but getting there.

Jonathan

 

[Daverw]

I also think that over the last year a lot of the initial stuff like which buss bars to use, compression or not, top and bottom balancing is getting clearer and many of these appear not as important as initially suggested.