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Lithium has the one major advantage of weight saving. A big plus for you racing guys.
It also has a big advantage of being able to accept a high charge current and will do so till fully charged. They don't tapper of as they get toward full charge like LA's do.
They do not mind being left partly charged, infact it is better for them not to be left fully charged when not used.
They can be run down to a low level with no damage.

CarbonFoam...that pricing is the retail price. So hopefully not too much of a big increase in cost here in NZ. But even if twice the price, still substantially cheaper than Lithium for very similar performance.
Disadvantage compared to Lithium is the weight. Compared to all other Lead acid batteries, there aren't any.

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Looks like carbon foam is even heavier than a comparable LA? 

 

I went with a 100AH Lithium house battery about a year ago and have been very pleased. Upgraded the alternator and regulator at the same time which needed replacing anyway, plus a good battery monitor. Big weight savings, plus so much quicker and more efficient to charge. Not the cheapest but hopefully better long term. 

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. Lithium can be cycled a but more so should last a bit longer.

Two things need to be factored into all batteries, no matter what chemical type they are. Cycle life and non cycle life.

An LA Battery will last years if hardly cycled. But aside form Gel, none of them like being left long term in a float stage. Leaving Li out for the mo, the others all need a cycle once a month on average to stop a phenomena called Plate Surface voltage. This is where the Plate looses all the plates charge internally and a residual voltage is left on the plates surface at the float Voltage of 13.4 or whatever the float voltage was. When you apply a load, the charge just crashes away. Some real cleaver Shorepower chargers have a stage in them that once a month, applies a load to the battery to discharge and then switches to Charge again and brings the bank up to Float to store it again. So hardly using an LA battery will mean it will last years longer. But eventually it will die and you have to also factor on for some cases, it is not point in spending big dollars on batteries if you hardly use them. The best way of working out a factor of economy for any battery was how many dollars per KwHr of use did you get. Length of time it sat doing nothing is not economical. It's like filling the car with Fuel and going no where and then saying my Tank lasts for ages.

     For Li, this is where the negative comes in. Lithium itself, is a very volatile metal. Right from the day the Li foil was made and wrapped up into a Battery, the stuff degrades. Used or not, Lithium is slowly degrading internally. A Lithium Battery has a life expectancy of about 3yrs, give or take. They do not like being left long term stored at full voltage. So you can not leave them float charged on Solar panels. Make sure they are at about 75% charge and disconnect them from charge when you leave the Boat.

So when viewed from a Cruisers point of view and when you factor cost into the equation, they are not the best choice. They are a very expensive $ to Kwhr item. From a point of view like KM, they are a good choice because they are light, they can be abused with not charging and deep cycling and they can be charged quickly again. They are most certainly a battery to have when in a High performance sailing situation.

The Carbon Foam have all the abilities of the Li, but the negative with them for the performance Sailor is weight.

 

In the background in battery world, other versions of Carbon Foam are being created. This is why I called this new battery Carbon Air originally. What the "Air"part i about is that the chemistry around the Anode is Oxygen and there is a Chemical change taking place that allows Electrons to be produced. It is not some light weight thing of just Carbon Fibre and air

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I am not sure on the warranty question. It could possibly be like advertised at X, but when you buy the product and read the actual warranty, you find that X is if you don't use it and reality is actually why. Like my mate here that buys AASolar batteries due to what AASolar say on website, only to find that the warranty gives the real info of warranty valid if cycled only to 20% depth.
Just this morning he found out his Bank has no had it's warranty voided. The installer did not set up thew depth of discharge part with the Inverter/charger. When asked why, the Installer said he had not been able to work out how with the software.
The batteries had been cycling down to 70% depth without him knowing till this this week when the Sun had played behind the clouds and the panels had not kept up. So I told him he better contact the installer and go him for replacement batteries.

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What Lithium did you go with jay?

Also is your a 13.2V or ??

 

I went with an AA solar 100AH lifepo4 battery (13.2v system), Balmar 80AH alternator and MC614 regulator, and Victron dual battery monitor. This is for an elliott 9, so weight / performance were important to me. Hopefully long term economics will also materialize. Fast charge time when cruising is very nice.  I have a switch so I only juice the alternator when I need to charge, and regulator is programmed to stop charging at 14.3v. Monitor tells me exact % charge remaining and current AH in/out, so real easy to keep tabs on charge state. I only bulk charge - no absorption or float. I kept my old LA start battery since it is still good. It probably gets under/miss-charged somewhat now, but hasn't seemed to affect it yet. If it does have problems, I can now start the motor using the Lifepo4 house. I don't have a BMS. Since I am only dealing with one 4-cell battery, don't fully charge and don't discharge below 50%, my hope is that risk of cell imbalance is sufficiently low, and easy enough to check occasionally. I also didn't install the optional temperature sensor. I limit charge rate to 40 ah. AA solar wanted me to install a low voltage cut-off switch to prevent accidental over-discharge to comply with warranty terms. I found a switch that has a safety manual override feature (many don't), but decided against it due to limited space / increased complexity and my own risk tolerance level. As a result, I wouldn't be able to claim warranty if something did go wrong which I'm ok with. 100ah has been plenty for cruising needs (waeco cfx fridge, stereo, lights, laptops). 

 

Wheels mentioned a calendar life of about 3 years for lithium - not sure what chemistry this is for? Lifepo4's are much longer expected life than 3 years.  For example,  AA solar provides a 10 year warranty. 

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Wheels mentioned a calendar life of about 3 years for lithium - not sure what chemistry this is for? Lifepo4's are much longer expected life than 3 years.  For example,  AA solar provides a 10 year warranty.

 

Yes they do, but you need to read the warranty on what that means. For instance, AA will fully replace the battery within a 1 yr period only. And even then, you have to provide the charge discharge history. Then after the 1 yr period, the battery is replaced at a cost summed by the 10yrs, or 120 months, So you divide the Battery cost over the 120 months and the battery is replaced with the ratio being what you pay for the new one. So that is not a 10yr warranty as such. Plus there are some stipulations other than just the Charge Discharge history. One I can't quite work out is the difference between Pure Sinewave, Modified Sinewave and Square wave inverters connected to it.

But yes there are different Chemistries of the Lithium range and it is really hard to keep up with them. Each has a specific benefit over another making their uses specific or more common with use than another. For instance, Li-ion or the Lithium Cobalt is one of the most common and found as Laptop, Tablet, Phone and Camera Batteries. The down side of them is a very short life span. Lithium Manganese Oxide Batts are found in Battery Tools. The Lithium Manganese Cobalt version is what is used for Electric Vehicles of all kinds. And within that one category, there are NMC, NCM, CMN, CNM, MNC, MCN which are all similar but with different metal combinations.

So there is.

Li-ion

LiPo = Lithium Polymer

LiFePo4, or also called LFP = Lithium Iron Phosphate

LiCoO2 or LCO = Lithium Cobalt Oxide and often simply called Lithium Cobalt

LiMnCo2 = lithium manganese cobalt oxide

LiMn2O4 = Lithium Manganese Oxide

LiNiMnCoO2 or NMC = Lithium Nickel Manganese Cobalt Oxide

LiNiCoAlO2 or NCA = Lithium Nickel Cobalt Aluminium Oxide

Li4Ti5O12 or LTO = Lithium Titanate

And even within each of those above, there are differences in ratios of the various Chemicals/Metals used. Plus quite likely, there are Lithium batteries I haven't heard of yet.

 

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Nicely said Wheels, LI chemistry do have a natural wanting to be fire however they can last quite some time. LiFePo4 should be 80%+ capacity after 4 years. I think i've seen some long life study somewhere, i'll dig it out

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Interesting bit from EV land:

 

"As evidence of a growing confidence in the 30 kWh battery’s cell chemistry (and the fact it will now take less battery cycles to go further), Nissan warrants battery loss below 9 bars of capacity (70%), for the first 8 years or 100,000 miles (160,000 km) in the US and in Europe"

 

I wonder what exact chem they are using, That are giving a 8 year 75% capacity remaining warranty

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 One I can't quite work out is the difference between Pure Sinewave, Modified Sinewave and Square wave inverters connected to it.

I think the cheaper inverters produce current spikes that confuse chargers. I ruined  a couple lithium power tool batteries recharging them using a cheap inverter before I figured this out. 

 

LI chemistry do have a natural wanting to be fire 

Lifepo4 is very safe and not a fire risk.

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I think the cheaper inverters produce current spikes that confuse chargers. I ruined  a couple lithium power tool batteries recharging them using a cheap inverter before I figured this out.

OK, bit of a long answer to this.

Firstly, re the Inverter, I would be surprised that anyone would be using a square wave. So I expect that could be ruled out.

Secondly, I assume that when AA Solar is referring to an Inverter, they would surely be talking about creating 230V from the battery. So the Inverter should not be producing any spikes on the suck side. You might see a slight ripple in the DC current drawn, but it should only be the actual current draw altering ever so slightly. Spikes could possibly occur on the output if the Inverter is dirt cheap nasty crap, but I have never seen any such spikes on anything I have ever tested with a scope. A modified Sine wave can sometimes upset some delicate electronics if the frequency or "sample rate" is not high. In other words, the steps in the wave are few and large. That can create a buzz in the AC.

However, as far as charging goes, a charger has either a Transformer or a Switch Mode Power supply in the primary side of the charger. Transformers are not good at reproducing the edges of steps in waveforms and then there should be good filtering on the secondary side. Switch modes supplies don't pass any of the waveform information on to the output at all and Switch mode is what most Battery tool chargers, laptop chargers and in fact most chargers and powers wall wart power supplies use these days. The ole transformer is a thing of the past. So I don't see what AA are on about.

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This thread has taken on a life of its own!. I believe that AA solar are getting a bit confused between inverters and inverter/chargers. That's all I can see would have an effect on the batteries. A pure sine vrs modified sine? That's going to be isolated from the batteries by a large bank of capacitors. The same caps which in our yacht have an inrush current in excess of 1000 amps momentarily. This is not a huge inverter either - a 1400w Xantrex Prowatt about 2 years old.

 

AA solar have some unusual claims in a few areas - as Wheels noted, the battery warranty requires you to have full data logging on the battery usage. Pretty unusual and a great way to avoid warranty claims!. I have no idea as to the quality of the batteries, I have seen them in several yachts, many motor homes and in some off grid setups  and not heard any complaints, so I assume they are good. I just get worried about the draconion warranty conditions.

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Thanks Wheels and Too Tall - the warranty was not a factor for me, other than as supporting evidence that provided I don't abuse the battery I should get a long life.  I only raised it as I was concerned about the three-year life comment. 

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The warranty and the life of the battery tell a story that many don't consider. A Boat system is designed usually with "minimum you can get away with" as the key word. Battery capacity to load always gets calculated with the thought that the Batteries will remain at full capacity forever. But in reality, capacity is constantly falling away and one has to factor in that if the Batteries are going to last 10yrs before you replace them, then they could be down to 70% of capacity and likely much more by then. Also, if a Battery reaches 70% in just 8yrs, then lets say 80% capacity in 6yrs. So one has almost lost one entire battery in a four battery bank. Either the system needs to be designed to supply the required load over 10 or more years, or one is going to need to replace the Bank in 5 to 6yrs.
Once again, I am comparing to a Cruiser situation rather than Racer.

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I don't race, and its not high on my priority list, so considering maximum weight savings is not my thing either. 

 

Jay, put simply, the less you take out of your battery bank between full charges, the longer it will last. Be it that you have 600Ah capacity and take 100aH out as a maximum, or you have 50Ah and take out 8Ah as a maximum, and you have a good charging system, you should get great life out of your batteries. 

 

If you took 300Ah  out of your 600Ah bank or 25 out of a 50Ah battery, your going to get a lifespan probably well less than half that of the above scenario.

 

However, if you don't have good charging controllers for solar, or a decent smart charger plugged in at a marina ( or other effective charging systems ) then your 600Ah bank might only last a year or two of "shallow cyclic use" ( less than 20% depth of discharge per cycle ) before its poked. To correctly charge any common battery system, you need a long absorption and float stage to get the last few "drops" in. Unless you run your engine for quite a few hours, you are not going to get that charge in to the batteries. 

 

A good battery monitor will let you know how much of the preset capacity you are using, and also gives a good indication as to when everything is fully charged. A fully charged bank will not accept any more current from float voltage which is set correctly for the battery. I believe this is pretty much the perfect definition of a fully charged battery / bank. When that input current drops to nothing, or next to nothing (>.5a) and the meter shows that you have replaced all the Ah back in, you should be maximizing the life of your investment.

 

Wheels, IT, I believe this to be a good summation of what the essence of making batteries last is. IT certainly knows how to make 'em last.

 

One thing I am not sure of however is how to consider an aging system. So lets assume you have lost 20% of the capacity of a bank. Is that bank now permanently at a 20% DOD so your once very conservative 20% maximum draw down has now become a much more aggressive 40% drawdown, or, does the bank just become a "smaller" bank, whereby your 20% draw down now has become a 25% drawdown.

 

IE - a 100Ah starting bank. 20% drawdown is 20Ah when new.

Once bank loses 20% capacity, does your 20Ah draw down on it  now get regarded as 40% ( 40/100 ) or as 25% (20/80) when considering the effect of a much higher DOD has on a battery?

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A complicated question to answer, depending on the Battery type. ie LA or Lithium. And even with Lithium, there is a difference between each type of Lithium. Lithiums are more about what takes place with the chemistry at the Terminal.LA is what takes place with the Chemistry within the plates. So decline is different between both types.
With LA, the declining efficiency is a two point issue. LA declines in both Stored energy and Voltage level. So not only does the Voltage level slowly become less, the stored Energy also becomes less. They are related of course, but as I understand it, Lithium loses stored energy, but the Voltage not so much. Lithium maintains a Voltage level over it's charge release and and then drops away abruptly, where as LA decreases in both Voltage and Current in a slightly more linear way.
With decline, the LA battery loses plate material and thus ability to store the same charge it once did. Providing it is not abused over it's life, sulphation occurs toward the far end of its natural life cycle. Sulphation causes a loss in a different way, in that the maximum voltage it can charge to drops, it's rest Voltage is lower and it's internal resistance increases and causes the battery to self discharge faster.
This is leaving aside individual Cell damage due to shorting. With Li, I believe the cells can fail with either OC or short. LA going OC is very rare due to it's rugged construction.
 

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Per AA solar's website, their lifepo4 battery can be discharged by 50% 3000 times with almost no loss of capacity. This is consistent with other data available on current lifepo4 battery technology and plenty good for me. 

 

Too Tall - what you say about charging is generally not viewed to be true for lifepo4 charging. They are much more efficient to charge all the way up the charge curve than LA with no need for long absorption or float cycles. As a result, I don't need to charge from shore or solar, as it charges so quickly from my alternator. 

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Too Tall - what you say about charging is generally not viewed to be true for lifepo4 charging. They are much more efficient to charge all the way up the charge curve than LA with no need for long absorption or float cycles. As a result, I don't need to charge from shore or solar, as it charges so quickly from my alternator. 

Yes, good call. I was referring to "traditional" batteries. I really should have stated that sorry. 

 

Going right back to the start of this thread - I am not interested in changing the entire system. Hence whilst the thread has moved toward discussing Lithium variants, I was still in the mindset of FLA, Gel or AGM. 

 

Incidentally, I managed to source a pair of new 12 v 150Ah c10 Sonnenschein industrial batteries for a very compelling price - $1.40 per Ah. Very comfortable with that although being industrial they are a difficult shape. 

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It's an interesting discussion. For me at least, it quite surprising how fast technology is changing and unless you spend large parts of the day chasing it all, it is hard to keep up.

 

Per AA solar's website, their lifepo4 battery can be discharged by 50% 3000 times with almost no loss of capacity.

 

That is likely very correct, but AA's warranty does not follow that.

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talk about lithium karma

 

Faulty batteries cause fire at Samsung factory 

 

.... it had sent out 110 firefighters and 19 trucks to put out the fire.

 

SDI is set to start supplying batteries for Samsung's upcoming flagship smartphone Galaxy S8 in the first quarter of this year.

 

The S8 comes after the Galaxy Note7, which suffered a global recall last year due to battery defects.

 

http://www.stuff.co.nz/technology/digital-living/89234622/faulty-batteries-cause-fire-at-samsung-factory

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