LiFePO4 - The future for off-grid battery banks?

[Mike90250]

Alleged dangers of charging LFP below freezing
Have read that LFP will degrade if charged at temperatures below freezing. Is this true only for the high C charging rates of EVs or is it also true for the very low C charging rates of solar in winter time. A vendor of LRP for LFPs said that the particular fabrication of CALB cells greatly mitigates problems at very low temperature charging/

We left our fifth wheel at son's place the last two winters where the temperatures got down to -20° F (-29°C). The parasitic losses were perhaps 400 W per day or about 0.04C per day. We have noted no degradation in capacity. Have planned to put in Halogen lamp (30 W) or a heating pad (30 to 50 W) in the front bay where the batteries are installed in the future. This is quite simple to do since we have 9.6 kW-hr of LFP.

Yes, below frost, only trickle charge. Do not rely on winter solar to be "slow", clear cold bright days bring out the highest performance of solar.
I would use a heating pad with a thermostat and a large heat spreader plate. If the light bulb burns out, you have cold batteries

[PNjunction]

May not make 10 posts as it seems those from the USA have only one intent, they are right and their USA products are the only ones that work. So they resort to infantile abuse of any who don't agree with their amateur and very knowledge less approaches to this technology, nor do they have any idea of what the state of the art is in the real world outside the USA. It's clear they have no experience or knowledge of the industry and expect companies to reveal the advantages they have over other installer and manufacturers.

Since you are acting as a commercial entity, you should know that the customer wants to KNOW WHAT THEY ARE BUYING.

Last time I checked, this is not a commercial forum, and soliciting PM's is already under fire.

Accusing us of being nationalist USA types, how about I offer something actual useful to users in Australia - and I'm all the way across the pond!

http://www.ev-power.com.au/-CALB-Lithium-LiFePO4-Cells-.html

and

http://www.evworks.com.au/

and maybe even these guys although I am not familiar with their products. But I offer it to demonstrate I'm not nationalistic.

http://lithbattoz.com.au/?page=about-us

Give me a break.

You gotta' develop a *thicker skin* to hang in this crowd. Good training for when you go into business for real.

[vudu]

Epic thread, laugh out loud

Good to see no one cares about this stuff.

It turns out I have 5+ years experience with LiFePO4 batteries - in solar led lights. I've had many, many solar landscape lights but there has been one stand out and it recently died on me. When I opened it up I was happy to find it was using LiFePO4. The battery was in surprisingly good shape compared to others I've seen of its age but I replaced it - it ran for two nights then died. Turns out one of the components died - not the battery. So I ripped it apart, replaced the solar panel and put it out in the sun. That old battery came up to 3.2V in just a couple hours.

That might not mean much in the context of this thread but it does show that individual cells can be used and abused in a cyclic nature over many years without being destroyed.

For a 'consumer solar battery bank' product to take hold - it has to be stupid proof so people like me can use it. LiFePO4 seems to have some of those qualities.

I hope someone comes along (like you Dax, show us what you got :P), in addition to Tesla, and makes a plug and play consumer version.

If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them.

Henry David Thoreau

The big benefit/goal, in my view, is enabling 'the grid' to be more decentralized - not (only) because I am suspicious of 'ma energy' but because it is a better architecture.

See what microsoft has done with batteries to save hundreds of millions in data centers:

http://arstechnica.com/information-technology/2015/03/microsoft-updates-its-open-server-design-with-a-battery-in-every-box/

If you zoom out and take that philosophy to the grid (where the grid here is giant banks of batteries, and the servers are consumers) you could lesson the size of power plants along with a multitude of other benefits.

Energy companies have no incentive to do it - it is up to the consumer to vote with their wallets.

[karrak]

Since you are acting as a commercial entity, you should know that the customer wants to KNOW WHAT THEY ARE BUYING.

As dax has said he is not trying to sell anything, he is just trying to counter the BS statement that LFP batteries only last two and a half years. He is trying to backup his argument by saying what experience he and his company have had with LFP batteries. He should be being thanked for sharing his experience rather than have you and others jump down his throat with comments that imply to me that you and and the others think that you know more and have more experience than he and his company. This is the same sort of treatment that was afforded wb9k who is head of the warranty labs at A123.

Last time I checked, this is not a commercial forum, and soliciting PM's is already under fire.

I can't see any evidence where dax has solicited anything, it was me making a comment about me sending a PM to him.

If everyone had been polite, we might have learned more useful information relevant to the topic of this thread.

Simon

[SunEagle]

As dax has said he is not trying to sell anything, he is just trying to counter the BS statement that LFP batteries only last two and a half years. He is trying to backup his argument by saying what experience he and his company have had with LFP batteries. He should be being thanked for sharing his experience rather than have you and others jump down his throat with comments that imply to me that you and and the others think that you know more and have more experience than he and his company. This is the same sort of treatment that was afforded wb9k who is head of the warranty labs at A123.



I can't see any evidence where dax has solicited anything, it was me making a comment about me sending a PM to him.

If everyone had been polite, we might have learned more useful information relevant to the topic of this thread.

Simon

Maybe. I have asked for more info and have not gotten anything I would find useful to be interested in purchasing that product.

If dax had been more forecomming with data instead of just his claims people might beleive his technology works. By providing useful data on a product you do not have to release company secrets. Just provide some actual data on testing or real life experience.

Telling us about how great the product is unfortunately has been done before by others who have not been totally forthcoming with the real facts. So why shouldn't people be cautious.

As of now even Tesla has a product that is "not ready for prime time" (translation; not a viable cost efficient product) but hopefully will have one in the near future.

Small applications of LFP technology, like in stand alone lighting or portable power sources does not guarantee that technology would work in a larger home energy storage system. I have heard and seen too many products that had been advertised as the "better mousetrap" only to be disappointed in their true performance.

[lkruper]

As dax has said he is not trying to sell anything, he is just trying to counter the BS statement that LFP batteries only last two and a half years. He is trying to backup his argument by saying what experience he and his company have had with LFP batteries. He should be being thanked for sharing his experience rather than have you and others jump down his throat with comments that imply to me that you and and the others think that you know more and have more experience than he and his company. This is the same sort of treatment that was afforded wb9k who is head of the warranty labs at A123.



I can't see any evidence where dax has solicited anything, it was me making a comment about me sending a PM to him.

If everyone had been polite, we might have learned more useful information relevant to the topic of this thread.

Simon

I don't know what thread you have been reading, but no-one here, as far as I know, believes it has been proven that LFP batteries last only 2.5 years. Would you please show me the post, in context?


Here is what I read that Sunking said:

http://www.solarpaneltalk.com/showthread.php?2214-LiFePO4-The-future-for-off-grid-battery-banks&p=174670&viewfull=1#post174670

''PN therein lies my main issue with LFP. You know the history of Chi-Com Prismatic LFP as well as I do starting with Thundersky just 8 or 9 short years ago. It is not a success story. From the start wildly exaggerated cycle life claims of 1000 to 2000 cycles. Two bankruptcies, and 5 product revisions later today and they still claim 1000 to 2000 cycles to 80% DOD. To this day I know of no documented Lithium any type that has a proven track record of 1000 to 2000 cycles. It is one thing to claim 2000 cycles with no proof or evidence vs say FLA with a 50 year history and proven track record of exceeding 1000 to 2000 cycle. 2000 cycles is about 6 to 8 years.

For EV especially DIY EV there is no other choice using Chi-Com Prismatic. It is the only game in town unless you get a chance at a salvaged EV pack. Otherwise price, availability, and thermal management are just out of reach$ of DIY. Solar you have 2 choices. Either proven Pb that is less expensive and last longer, or a gamble on Chi-Com. As of now we are still 6 to 10 years from knowing if LFP works or not as claimed. ''

Sunking said that we are 6-10 years from knowing if the claims about LFP are valid. In this very thread he encouraged someone who had done the proper research to try LFP if he knew what he was getting into. Why would he do that if he KNEW they would last only 2.5 years?

The ones who are making these claims without proof deserve to be put on the witness stand and cross-examined like the hostile witnesses that they are. They make these claims without proof and anonymously. If you don't believe this, then show me the proof!

[reed cundiff]

Yes, below frost, only trickle charge. Do not rely on winter solar to be "slow", clear cold bright days bring out the highest performance of solar.
I would use a heating pad with a thermostat and a large heat spreader plate. If the light bulb burns out, you have cold batteries

Thanks for reply. My question is how great a C would be safe trickle charge with LFP cells.

[karrak]

I don't know what thread you have been reading, but no-one here, as far as I know, believes it has been proven that LFP batteries last only 2.5 years. Would you please show me the post, in context? ...

The ones who are making these claims without proof deserve to be put on the witness stand and cross-examined like the hostile witnesses that they are. They make these claims without proof and anonymously. If you don't believe this, then show me the proof!

You can buy and operate a FLA battery for 5 and a few up to 10 years. There are a couple out there. A really good FLA cost around $200 to $250 per Kwh. If it last say 5 years means just in battery cost alone you paid $1250 / 1825 days = 69-cents per Kwh just for the batteries. You want AGM or LFP? They cost twice as much and last half as long. That means $2500 / 913 days = $2.74 cents per Kwh or 4 times more than FLA.

Simon

[azdave]

Not revealing our company, not here to promote it or sell anything, just to put forward what we do and have achieved, so others can see the real situation and not the deluded one put forward by day dreamers.

...I know of two other major lifepo4 installers in Aus who make their own lifpeo4 control systems like us and use pretty close to the same quality cells we do, all from Asia.

If you don't want to reveal your company yet okay.

Who are the two other companies you mention so we may research their offerings as well?

[lkruper]

Simon

I can see how you could interpret what Sunking said in that fashion with this general statement, even though he did not say 2.5 years. However, if you take all that Sunking said in his posts with more detail addressing the question, it would be wrong to characterize his view as being dogmatic that LIFEPO batteries can only last 2.5 years and continually harp on that one comment.

I would hope that if I were to be quoted by you, that you would consider all that I have written in the same thread together and in context. You would probably want the same treatment, wouldn't you?

[Mike90250]

Quote Originally Posted by Mike90250 View Post
Yes, below frost, only trickle charge. Do not rely on winter solar to be "slow", clear cold bright days bring out the highest performance of solar.
I would use a heating pad with a thermostat and a large heat spreader plate. If the light bulb burns out, you have cold batteries

Thanks for reply. My question is how great a C would be safe trickle charge with LFP cells.

Only the cell mfg can give you that data, for cold temps charging. It's so small, that you are better off running a generator to heat them up above freezing (all the way through the middle) before resuming normal charge. Their internal resistance is so low, there is little self heating in solar applications, that a simple insulated box won't be much help.

[Living Large]

Only the cell mfg can give you that data, for cold temps charging. It's so small, that you are better off running a generator to heat them up above freezing (all the way through the middle) before resuming normal charge. Their internal resistance is so low, there is little self heating in solar applications, that a simple insulated box won't be much help.

This is great factual, practical information. Not the "dumb, infantile abuse" rhetoric I expected to find after reading a newbie's post - someone who apparently can't be troubled with technical details. Thanks!

[dax]

One thing I've learnt here, there are very few who have any real experience with decent size lifepo4 packs, no business or R&D experience with them and have no understanding how they really work in use. Basically it's mostly pure ignorance and reliance on dumb info relating to the FLA mind set and brain dead ego's.

Lifepo4 don't cycle like FLA, nothing like it. So all the claims of numbers of cycles are the same as claiming a god exists, primitively dumb and blind to reality. Was going to explain it, but after the infantile abuse, there is not a hope in hell of that information being revealed. You can find it for yourselves and not go through the large amounts of money we spent in R&D and 6 years to get to this point.

This is our business, no way are we going to reveal what keeps us at the front of the industry, So funny that someone would run our cells down, then post a link to an Aus company who has just woken up to the quality of the type of metal cased cells and densities we've been using for the last 5 years and they call cam72. If they use 3.65 charge voltage as they claim, they will stuff them within 3 years. These cells hate going over 3.5 volts and there is very little usable energy above 3.5v and below 3v, the majority sits between 3.2 and 3.1v, Which is another form of evidence, you all still use FLA mind sets and not lifepo4.

Successful long term R&D business like ours, do their due diligence with their products and services they are developing, it has taken us 5 years of R&D to get to this point. They have a business and development plan, like our 5 year one and companies that want to be successful undergo this approach to new technologies and business directions. That's why no one has heard of us, but if you have no idea of running successful business, then you would be blind to that reality, or so far up yourself, you'd never be a success in a R&D style business. That's what we've been in the building industry since I started my building business 40 years ago, hence the move to lifepo4 systems.

Drop kick fly by nighters with no knowledge and looking for a quick dollar, jump in using parameters they find on the internet, told to them by some on line jargon speaking dummy, or from supplies who don't have a clue, but love the idea of lots of resales. Then cover it all up by providing a load of useless technical knowledge, the average user has no idea about and doesn't want to know. That's where our market is, not in a bunch whose only claim to knowledge comes from a keyboard search on the net.

Go out and stuff up tens of thousands of dollars worth of cells, controllers, inverters, relays and electrical equipment like we've done over the last 6 years, to get to where we are, then you may have a clue as to how they really work and realise how long they can actually last. Especially when you know those you bought them from, provide a decent warranty, can repair any cells or components that may go wrong and when your cells are beginning to degrade in their capacity and ability to provide decent currents, you can trade in your old cells for new ones, reducing the replacement costs. Thats how a business looking at the long term operates.

If any of you had a business brain, you'd do your sums, economies of scale, due diligence in market placing, competition and back up systems. Develop a business plan, put it in to action and when it is proved, release to the market. After during the first year of mucking round with the cells we developed our 5 year business plan, put into action, proved it with 2000 installs in widely differing situations and environments and now have products which have been proven in action.

As I said earlier for any who want to listen, the charge and discharge parameters I posted earlier, are the ones we've found provide the best outcomes for lifepo4 long life and minimal cycling. If they are stuck to, in our experience, the life time for them is only limited by the environment they operate in. Temperatures from below zero, to 8deg, without proper temp control on cells, they lose the ability to provide large current draws within 2-3 seasons.

They are wonderful for starting engines, but suffer from the huge temp change under the bonnet and if the vehicle is left out in low temps, your lifepo4 won't last very long. Large capacity slow draw systems, don't suffer that problem as much, but if you want your liifeppo4 to serve you for a very long time, keep them at ambient temperatures above 8 and preferably between 15 and 22 deg C and they will be fine. We found 18degC is pretty much a perfect temp for them, not to hot nor to cold. We have moved our starter packs, to inside the vehicles and not under the bonnet and in some machines are heavily insulated to protect them, We've tried heating pads, coils and air warming devises, and are close to coming up with something that doesn't take anything out of the pack when they sit for long periods in low temps or over 25degC, so it is important to isolate your pack if you can. We think we've solved temp problems for big packs and high temps, the technology just have to be proved over the long term before it is incorporated in our systems. Now we are working to implement it in starter systems and should get that done this year.

When dealing with consumers, the technicalities mean nothing, it's the performance, cost and reliability of what they purchase that they seek and that's what we provide. Babble all you like, get some ego trips out of being abusive when faced with facts and realities you don't understand and deny, because it doesn't fit with your programmed mind set. It's your problem not mine and will cost you in the long run and probably already is but you are yet to know it, because you're stuck in la la FLA land with no idea of reality.

[Living Large]

Luckily, there is some degree of freedom of speech here, and the lowly infantile people with the massive egos and dumb ideas and no grasp of reality can appear as stupid as they like to you. And there isn't much you can do about it, except comment on it.

[PNjunction]

Guys - everybody is making *claims* which are unproven so far simply because we don't have the calendrical life to adequately test our cells under real-world conditions to go a decade or more.

So far, there is only ONE place that can come close to doing that without stretching the calendar based upon using lab equipment (which no mortal has except these guys in the educational funding realm) to watch the parasitic reactions and use THAT for making predictions - or we can just wait it out a decade and cross our fingers - despite doing the conservative charge/discharge thing. Jeffrey Dahn at Dalhousie University, where commercial manufacturers send cells for testing that go well beyond just doing repetitive hammer-cycling which is only beating the parasitic clock. One of the guys who built it went on to work for Tesla.

I don't know how much it costs to send cells for testing, or what the acceptance procedure is, but this is worth watching at Dalhousie University. If you look closely, there is a column for LFP, although much of the discussion is about non-lfp cells. Still the basic background info is priceless. Oh yeah, I have Canadian friends too!

https://www.youtube.com/watch?v=9qi03QawZEk

If an Australian lurker lucky enough to read threads backwards, and wants to avoid all the drama, the lithbattoz guys seem to be a way to go in one place. The simplest of course would be to get a simple 12v 4S (4 cell) battery of the capacity of your choice, a "single-cell" charger, and if you like a pack/bank level charger.

None of this is new if you've been doing LFP since 2008 or so. T1 Terry has. Maine Sail / Compass Marine has. The infamous Jack Rickard (whatever you think of him) has. Of course WB9K, who doesn't hide the fact that he works for A123 has, Doug Ingraham at DIYelectriccar has, and of course input from our other well knowns like SK and a host of others. Many of these early pioneers are in other places enjoying some peace and quiet. We kind of serve a purpose here to keep the LFP drama zoo in one place.

It isn't rocket-science. I think that's what upsets the apple-cart the most and creates the most drama.

In all cases described above, DETAILS are provided.

Dax - read the thread from the beginning. It hurts, I know. You'll find that I agree with you on nearly all of it. I just have an issue with a proposed business venture having conflicting interests - starting with the recommendation not to use large-format cells. That was the red flag.

Can we move beyond the business side of things, and get back to the purely technical without any side-spin?