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Forum Index : Solar : 48volt flat packs

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brucedownunder2
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Posted: 09:01pm 18 Nov 2020
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Hello,
I see ,mentioned in a recent post,in this section, a bit about ,Flat-Pak. Batteries.

I saw an example of one the other day in my wandering through a used building sale yard.
It was a LG 48 volt heavy black steel rack unit that presumably is full of Batteries?.

My question is ,would this ,being some 2.5 Kw @ 48 volts be worth thinking about for future Battery Bank in a rack,say ,a few of them?.

It had Two rather large Output Terminals, but other than that,I did not take it out of it,s cardboard box—-it looked brand new!.

Thank You

Bruce
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Davo99
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Posted: 06:40am 19 Nov 2020
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Would batteries be worth it is a very " How much string do I need?" type of question.
Depends on a lot of things.
I would suggest the form factor of a battery is irrelevant.
To my mind, the thing that is important is how much bang for the buck.

You would have to get batteries VERY cheap to save any money if you have grid power and solar. The ROI on those can be quite quick especially if you bootleg it and install used panels. If you could get batteries at a cheap enough price so you save more than their and the rest of the setup costs over their lifetime, great.  Weather they are LA Lipo or whatever is beside the point. It's how much capacity you get for your $.

From what I see, used batteries are most often like used solar panels, completely over valued. People seem to have this idea that batteries ( and panels) mean you'll never pay another bill again. Even if that were true, it's the cost of the batteries etc you have to consider.

I have seen a lot of advertorials where they show Fred Nurk and his Family and talk about how they were paying $1000 a Quarter for power. They put in ( an Inevitably Tesla) battery and not they are only paying $500 a Quarter. They carry on like the battery was free and completely disregard or mention in quick passing the $15K cost of the battery which they are now paying off instead of the power Bill.

They are a lot of calculations and twisting there of employed with batteries but I like to break it down to one simple one to start which is usualy as far as one has to go....

Will the battery save more than it's cost over it's life time?
Almost without fail, If you work out the cost of the power they save if used to capacity every single day ( which will never happen anyway) against their cost amortized of their life expectancy,The things STILL fall way short of paying themselves back.

If the cost is lowered so the numbers do add up, Then fine, by all means use them.... IF they will actually save money.

I have been looking at some US based solar forums of late. They sure do have a different way of looking at things!

They seem obsessed with blackout protection when they admit they might happen a couple of Times a year for a couple of hours on average. They seem quite OK with literally spending $5-10K on batteries, Inverter etc for that but the idea of Go buy a $1000 generator seems very offensive to them.  A guy the other week was talking about backup during snow storms and of course wanted enough power to run a Supermarket for week.

Some people pointed out the cost of having enough batteries for what he wanted to Run and I said don't forget, this will be one shot because if there are snow storms, there will be no light of any merit even if the panels aren't Covered. I suggested a quality Diesel generator but he seemed determined to stick with the battery panel idea even though others were talking about $30K to do what he wanted.

I also mentioned with a Generator he could co-gen and use the heat to warm his house which would also reduce the electrical load..... Substantially.
He made out having to Refuel a generator and change the oil once a year would be too much of a Burden and preferred the battery route.

I'm sure some salesman somewhere will be very glad he walked in the door!  :0)


I know which damn way I'd be going without a second thought!

See what they want for the batterys and do your sums from there and see how they pan out. You might be Lucky.
 
brucedownunder2
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Posted: 08:28pm 19 Nov 2020
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Thanks for the reply,Dave.

Very constructive thinking,.  I totally agree,
It,s so important to sit back and evaluate the costs. I tend to consider any cost versus the effort input and most times find that the savings are just not there,unfortunately.

But, having said that , I keep. Reminding myself that ,in my case, this is my hobby ,and so therefore a whole different set of costing versus pleasure comes into play....

I guess it,s not much different to the yacht I owned,  I keep reminding myself of the analogy of standing under the cold shower tearing up dollar notes ?...

Back to the batteries, my way of thinking is that technology is changing and these new flat pack batteries will in time be the norm ,because of handling,their size,and rack mounting cosmetic appeal.

Like I agree with you , if I can get this deal for a reasonable ,hobby, price ,I ,ll give them a go , mainly to check out the charging effort, capacity,

Thanks, Dave for your honest and I think, sensible post,

Bruce
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Davo99
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Posted: 10:00pm 19 Nov 2020
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I know where you are coming from Bruce.  If I could get onto even a small pack at a reasonable cost I could Justify for hobby purposes, I'd be all over it just for learning value.

I Played around with a Tiddly winks batter set up, couple of Car batteries with panels, Charge Controllers and Inverter as my first experience with solar and learned a LOT with it.  To do much more than that I could really justify because my power costs me basically NIL right now with the solar I have so it makes  the viable price of batteries pretty low . :0)

Every time I read about Batteries the parroted mantra is the will get cheaper with the implied inference that one day they will be virtually giving them away.
I'll flat out say they are not going to get much cheaper at all, In fact I think the price will steadily climb for all types.

People, and I'll call a spade a spade, business uneducated people, seem to think that volume makes price drop. It only does to an extent with a new Technology as development costs are recovered and manufacturing costs are streamlined. These days the Chinese knock off factor comes into it as well.

The problem with the battery price reduction is demand is Huge and virtually endless.
Everyone wants them From phones to power tools to cars and Home batteries and 1000 things in between.  High demand in business does not lead to low Supply price. People also think that everything is based on the market strategy of " Cost of Goods sold" When that's Far more rarely used than the " What the market will bear" Business Model.

Like oil, won't give a damn  if they can make batteries for 2C a ton, With a demand they will virtually never fill, the price will be kept high because people are in business to make money not give the customers the lowest price.  As it is, battery manufacturing is NOT cheap and the Chinese are already into it and The cells they are producing are not going for giveaway prices either.

My Typically against the grain prediction is that battery prices will continue to rise. While many of the elements in batteries are in abundant supply, Refining them is a whole Different matter. It's really only the 3rd world countries with little to no environmental protections or corrupt Gubbermints that refine a lot of the materials because to do so in the western world would mean batteries were Cheaper to make from 24K gold.

Even going back to basics, How much cheaper have the common lead acid batteries got over the last 5-10 Years?  Very old tech that is well understood, Probably several Hundred Million of those made a year and they haven't got what I'd call Cheap  yet they fit all the criteria that people say the new Lipo etc batteries will become cheaper for.
I don't think so Tim.

People in the US are using Old car packs but even those I wouldn't call cheap.  There is a demand for them and when there is demand the price is elevated to knock the people like you and me out of the market. If you are off grid and have to have them then people will pay whatever. There are many people whom think it is helping the environment or just plain want to keep up with the Joneses and they too will pay the asking price whatever it is pretty much. There is well and truly enough of those people to keep the market going for a very long time until demand falls off and that's just the private market, The industrial/ Commercial market is only going to ramp up magnitudes as well.

Throw in one interruption to supply from one of these politically unstable Countries supplying or refining the base materials and prices will skyrocket.

Yes, there are new Technology's coming out aiming to reduce the material costs but again, a New tech has a pay back period before the price settles and if it's newer and Cheaper it will be in high demand to the costs reductions won't be that significant I can see. If a manufacturer can save $20 on a product they produce, might be worthwhile for them but not really going to effect the price as far as you and I and a lot of other people are concerned.

I also doubt there will be some massive break though that suddenly drops the price. Batteries aren't new and they are something the world hinges on right now. There has been a lot of research put into them for a lot of years so while I would say that progression is undeniable, I think it will be that, slow and steady rather than some massive breakthrough coming.  They have tried a lot of things already. They are into exotic materials now for capacity and weight and price will be a bit further down the priority list.

I can see a market for flat packs for sure. Apart from anything mobile, with new homes being built more and more to the average size of a show box, a children's shoebox at that, having a Battery pack that could fit in a Cupboard would be well received in the market. Luckily I and I think many of us here would have the space for a Boring old large, heavy untrendy Forklift pack which from what I have seen repeatedly is the cheapest  and for me, best alternative in a lot of ways.
As I have mentioned here before, one of the somewhat hidden advantages is their scrap value.  It's about 1/4-1/3rd of their purchase price atm.  If you had them even 10 years then the scrap price could well go up a lot higher. I can't ever see it coming down that's for sure.

I think one would have turned a pretty unique shade of Blue from holding their breath waiting to see any dramatic reduction in battery prices for many decades yet.
 
nickskethisniks
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Posted: 08:18am 20 Nov 2020
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Good read, sadly you are spot on!

What I will do next time if I want batteries, I would buy from Alibaba (if I could I would buy in EU but there are no lithium batterycel manufacturers here...)

If you want the square lifepo4 100-280Ah cells, you can buy those at the moment for 100€ /kWh delivered. These are been tested by a lot of people now and tested amazingly good. No idea on the long term.
That's cheaper then all those refurbished, Tesla, Nisan, etc batteries, and lifepo4 is a far more superior chemistry for storage capacity.
Winston etc, is more like 330€/kWh.
 
Davo99
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Posted: 09:36pm 20 Nov 2020
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  nickskethisniks said  

If you want the square lifepo4 100-280Ah cells, you can buy those at the moment for 100€ /kWh delivered.


I think these are the ones I have been reading of and the Americans seem to be going crazy for.  I didn't pay much attention to the price but it does seem good.

Bit of quick calculation and conversion,  That would make a 10Kwh pack around $1162 Aud.  If we take our ( highly Variable) Price of power to be .30C kwh which I think is pretty mid range and common, That would mean a repay on the pack of around 13 Months -IF- you used it to capacity. In reality for most people that may blow out to 18 months as most people aren't going to be able to charge to capacity or use it all every single day all year round.

One would have to add in the BMS, charger and inverter as well as the wiring.  As a rough guess that would Triple the price if not more.

Still, If one could get a 4 Yr payback, thats on par with solar ( which you'd have to add in if you were starting from scratch)  which isn't bad.  The batteries one would think would last a year, 4 or 6 years for a full ROI puts them back in the questionable  area at  this stage because they are new and from what I read, there is more than one Company doing them and no real way to determine their longevity.  

Not trying to be negative but in thinking of my own repeated experiences with these type of batteries in the things I have had with them, I find that time frame to be questionable. In fairness, I also question the life cycle of 18650 batteries used in Vehicles like Tesla's which are supposed to have 10 Yr lives. Best I could ever get with them in something like power tools or not overly used laptops on battery was around 3-4 years before I saw noticeable dropoff so..... still a big question to me.

While I don't buy into the " All Chinese is Crap" Mentality because I know better,  I am also wary of the " Cheap Chinese" products and have found in order to be cheap, they generally cut quality. In a battery pack there isn't much to cut without cutting into quality and life expectancy.
Looking at the way the American DIY'ers are buying them up ( and paying quite a premium for their own import costs) There are either going to be a lot of happy people or not so happy in the years to come.

While a lot of Americans have this thing about mucking round with little 100W panels and think  3 of them should power a Hospital, They do seem to go large on battery banks and not afraid to spend big bucks on them. Not sure why, just the sort of mentality/ Culture I have picked up on. If these batteries fall short of expectation, I think it will leave a real negative impression of  batteries overall particularly anything out of China.  Will be interesting to see how it pans out.


If one had all the support gear and just needed a battery pack, these things do seem to offer a good chance of being Viable.  If you had to start from scratch, I'd say a significant risk BUT, might be possible to recover costs on the second setup if you only need to replace the batteries themselves.

The price seems OK with these, The question and the other side of the equation remains though, will they last long enough to recover their Cost and more over, the total cost of a battery setup over, Primarily, The cost of a solar only system  and the savings that can make on ones power bill.

This is a bit of a grey area because these packs would be used in a DIY system which grid connected would probably not be Kosher. The same DIY'er is also more likely to " Fudge" the rules and regs on solar and over clock the inverter or DIY some more inverters to the system so probably realise even greater savings and minimise their bill without batteries and at a far lower cost.

The life expectancy of panels seems to be determined by everything BUT the panels themselves.... Inverter failure and  stupid regulations requiring system replacement, bad weather, necessity to remove for other work, desire to upgrade and so it goes.
 
Warpspeed
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Posted: 03:07am 21 Nov 2020
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My own personal experience is with 6Kwh of Winston cells, of which there are thirty. The cost of just the cells was just under $3.5K.

These have now been in service for three years, the bad news is that three cells have very suddenly failed totally, dead short.
The good news is that the other 27 are working fine without any obvious loss of capacity.

So not really sure if that is a good or a bad result.

Several Forum members are using second hand 48v fork lift batteries with great success.
Cheers,  Tony.
 
Davo99
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Posted: 06:47am 21 Nov 2020
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  Warpspeed said  My own personal experience is with 6Kwh of Winston cells, of which there are thirty. The cost of just the cells was just under $3.5K.


Tony, were these a cost saving measure for you and if so, what is the repay time for you, or, were they more for a curiosity/ hobby?

  Quote   These have now been in service for three years, the bad news is that three cells have very suddenly failed totally, dead short.
The good news is that the other 27 are working fine without any obvious loss of capacity.

So not really sure if that is a good or a bad result.


Spose it depends on your ROI time and how long the rest of them last.
10% failure rate, so far, is a bit of a worry to my mind.

  Quote  Several Forum members are using second hand 48v fork lift batteries with great success.


Yes, I think if ever I went battery that is the way I'd go. Even if I had to lay a slab and put up a garden shed to house everything in that wouldn't be a problem for me but I can see where the smaller lipo packs have many advantages for other peoples situation.                  

The problem with these " new" batteries is one really can't tell how they are going to go till really it's too late.  You could get great batteries that are well worth your investment and pay themselves well off.  When they do eventually die one would be lucky to get the same batteries again.  The  tech may have " Improved" but every time they change, one is back to square one.

If they do fail sooner than they repay, they they are still probably superseded so one takes the same chance again.  I think one has a better chance of knowing what one is getting with LA because the tech is pretty standardised and understood.   Not sure if that will happen with the lipos but hopefully they will be all close enough to get a good idea of what they should do.

I'm not sure any china battery manufacturer would give any meaningful warranties and they may be just as questionable from anyone else as well unless one goes back to paying the totally non viable prices from the known manufacturers and then the whole exercise is pointless.  :0(
 
Warpspeed
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  Davo99 said  
Spose it depends on your ROI time and how long the rest of them last.
10% failure rate, so far, is a bit of a worry to my mind.


Best ROI is not to have any battery at all. Run off solar during the day, and a mains powered dc rectifier at night. During summer, grid power consumption reduced by 80%.

At night obviously some grid power is always used, no matter how many panels, so its not possible to do any better than about 80% in summer.
During winter average grid consumption reduced by 45%.  Some days solar is zero.
But over say a month, grid power is easily always less than half what it was without solar.

With a battery, I can go completely off grid any time of year, but choose to use some minimal power each quarter just to maintain my grid connection.
I have three phases here, and my big welder, lathe, and air compressor are all three phase, and always must run direct from grid power.  
During a grid outage I can live without those.

My battery is small, only 6Kw hours, so air conditioning at night is not possible.
I can run air conditioning all day longin summer off solar.
In Melbourne we might typically have a run of about about four days of  40+ Celsius temperatures just after Christmas, and I then run air conditioning at night off the grid. The daily cost to do that is huge but its only four days a year, and overall in the great scheme of things is insignificant.

So basically I can make very substantial electricity savings without any battery at all, and if money was the only criteria, that would be the way to go.
I ran it for over a year like that, so the figures are pretty solid.

But a battery is very nice to have during grid outages, and I could go completely off grid for long periods if ever required.

I have a home brew natural gas powered standby generator about 90% completed, its small only 1Kw, but its more than enough to run everything right through mid winter, the battery taking all the big short term loads, and solar/generator recharging at a slower rate over several hours.
The standby generator will be fully automatic start up and shut down when completed, and using natural gas means zero manual refueling ever.
Must pull my finger out and finish it off.
Cheers,  Tony.
 
nickskethisniks
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Posted: 08:01am 21 Nov 2020
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I think there are not much reasons to go in batteries today for normal grid users.

Although in Belgium we are now getting paid ?€/kw for injecting but still need to pay full price for using the same energy we once have injected. There will be digital measurements on the injection and extraction. And they plan to get us paid for "peak load". By a certain date they wants us to have all digital meters, like my parents they have one for more then 12years now.

In that case a DIY system would pay back, but forget it with a commercial system like lg, Tesla,...which infarct raised there prices! Although battery price is going down...

They (Tesla)are now also investing in lifepo4 and if I remember correctly will implement the lifepo4 technology on there cars.

It's not the technology, it's been there for years, I do own Valence Saphion batteries produced in 2006! Some with 90-95%original capacity/! Man if I knew they were that excellent... I would have gone al in at 150€/kWh ( second hand) for I think retail of 1500€/kWh back then...

And slightly used headways (+-8years) cells with original capacity!
Maybe IR and Wh dropped a bit but still...

I went for the "hobby" and to invent some things around it.:p

I find it very troubling those Winston's go short circuit without reason. For me those are the holy grale. A few months ago I did recommend these to a colleague's as best/safest batteries on the market for his RV.
Should be a production flaw... Did you test them individually (capacity, ir?) Are they clamped?
Just looking for answers...
Edited 2020-11-21 18:06 by nickskethisniks
 
Warpspeed
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  nickskethisniks said  

I find it very troubling those Winston's go short circuit without reason. For me those are the holy grale. A few months ago I did recommend these to a colleague's as best/safest batteries on the market for his RV.
Should be a production flaw... Did you test them individually (capacity, ir?) Are they clamped?
Just looking for answers...


I have an excellent cell voltage monitoring system, generates a histogram display on a VGA monitor. I can see instantly what every cell is doing, one VGA display out in the shed, a second in my kitchen.
Also have a dynamic full time cell balancing system that switches loads across the higher voltage cells, which is part of the cell monitoring system.
Charging terminates as soon as any cell reaches 3.45v.

The cells have not been thrashed, never charged beyond 3.45v never discharged below 3.10 volts.  Automatic battery disconnect beyond >3.5v and <3.1v, and any individual cell will disconnect the entire battery if one goes out of limit.

I had three undervoltage disconnects, and in each case the measured cell voltage was zero.
Not one millivolt or two millivolts, but zero volts dead short. Each cell had very slight swelling even though clamped six cells deep between two 6mm steel plates.

Klaus has had at least one cell do the exact same thing.
When Klaus reordered a replacement, Trev said he had never heard of such a thing ever happening.  So I really do not know what to think.

Here is my early BMS design (2019) showing thirty cell voltages, plus the max and min peak voltages reached for each cell. The circuit breaker has a shunt trip coil to disconnect the battery if any cell goes beyond limits.You can see charging terminated when one cell hit 3.45v exactly.



It would be difficult to engineer in more monitoring or more protection, but three cells still spontaneously died in the exact same way over three years.

This is my latest version with a much higher resolution home brew video board, just the bare VGA board under test, not hooked up to a battery here. The voltage bars change colour when the discharge load is active on a particular cell. Pretty happy with how its turned out. The crappy photograph below looks grey and grainy, in real life its really crisp and sharp.

I am just slightly fanatical about looking after the battery as you can see, its quite an investment.
But all these cell failures are still rather worrying.
I still need to order three new cells from Trev, running without the battery right now.


Edited 2020-11-21 20:27 by Warpspeed
Cheers,  Tony.
 
Murphy's friend

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  Warpspeed said  
Klaus has had at least one cell do the exact same thing.
When Klaus reordered a replacement, Trev said he had never heard of such a thing ever happening.  So I really do not know what to think.



Its two Winston cells (200Ah size) that have shorted now.
I have 8 of them 8 years old and another 8 only 4 years old. They all are connected in series.
The first shorted cell (over a year ago now) was of the newer lot. The second short at one of the older cells so age seems to have little to do with that cell shorting mystery.
I replaced the second bad cell with a used one (8yo). The battery bank seems to have half its original capacity by now, plan is to replace the lot in a few years (at 25%) with new cells. Yes, its just a hobby for me but albeit an expensive one.

There was no drama upon cell shortening, just loss of battery bank voltage.I cut the bad cell open, nothing obvious looking like a short to be seen. Just many many meters of copper & aluminium foil separated by a plastic membrane that smells funny, no liquid in these cells. The foils are very tightly rolled into an elongated shape, the lot looks like the inside of the old foil capacitors. Very beefy terminals (copper & aluminium) on top.

I now use the Deligreen BMS system as recommended by Trev. He suggested to charge up to 3.6V which I do. The cells settle at 3.5V fully charged with 30mv between the old and newer cells at most.
 
Warpspeed
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Whatever happens, its very sudden and without any warning.

One day its perfect, the next day the overall battery voltage seems a bit low, and one cell in the series string has gone right down to zero volts.
Cheers,  Tony.
 
Revlac

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"harmful dendrites and whiskers in lithium batteries" can lead to failure.

I was told some time ago, not to run these (18650) lappy cell's at too lower voltage, not sure the exact reason but it makes them more difficult to manege and also added a noticeable resistance to charging, not nice, after 2 weeks it seemed to improve a bit.
Now I don't let them run too low anymore, its only about $1.00 or less in Diesel to do a bulk charge if there has been a bit of bad cloudy weather with little solar power, not often Here in QLD

We wanted to get three phase power here but that would have cost a fire bit to do poles where in place and the electricken (chickend out) advised us how he wanted the last power poll put in (did it our self), he never come back with a quote, so that was it.
We have always had generators and for the 3phase gear its no big deal to start the big Geny to run the big lathe to do a job, it wouldn't have used any more than $30.00 worth of fuel per year, just to have the grid connected here is over a $1 a day last time I checked.

At least with most of these battery types if a cells fails it can be replaced even though it is a real PITA and downtime you could do without.

Even these flatpack type are designed to add onto despite there age and capacity, I have no idea what type of cell they have in them, but if something has gone bad it may be possibly to replace some, unless they are pouch cells that are glued in, then it can be difficult so I've read.
Cheers Aaron
Off The Grid
 
Davo99
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I learned one thing here, These cells are not for me if ever I went battery.
I have neither the skill, knowledge or patience for looking after them and knowing myself, I'd say the desire would fall off pretty quick as well. Clearly they are like a pet that require constant attention and care and they would need a more responsible owner than me!  :0)

I read up a bit on these Chinese 280Ah Cells. There seems to be a bit of variation in reports with them, No doubt due to individual management practices. One thing seemed a common thread, To get the rated capacity out of the things took a LOT of very careful balanceing and Charging.
Seems most people get around 250-260Ah out of them which isn't a big loss but it's more down to the management that strikes me.

I'd be happy with something I could do a balance once a month and check the water and cells but I think beyond that, they would be neglected and that would not be good.  

The battery's  seem the Minor part of these setups. I can see why there is so much said of BMS can controls for these types of cells.
 
Bryan1

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our sonnenshein 600ah batteries only lasted 9 years and I replaced it a free new 24 volt 600ah forklift battery, this battery is still going today and in full summer we can go weeks with needing to throw on the genset to charge it.

Likewise with my 24 volt 735ah forklift battery in my shed only about 750 watts of PV and my old 100 series F&P NOT re-wired just wired in delta and using the same cap bank that guy from down south came to see then ripped off my idea.

When this battery finally goes we will be going 48 volts only if our SA32 inverter gives up the ghost but sofar it has run for 18 years nonstop with no problems (touching wood here)

Cheers Bryan
 
Davo99
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  Bryan1 said   this battery is still going today and in full summer we can go weeks with needing to throw on the genset to charge it.


My idea with a battery/Controller where possible and I see no problems, would be to over panel the heck out of it like I do my GTI's so for the most part, the battery's were effectively " Ballast" and the majority  of the power came direct from the panels during daylight hours.

If I took my winter heating loads off electricity, I could easily run all year round with no power other than solar. Used panels are very cheap now especially the older sub 200W Types and basic charge controllers that could do the bulk charging and "direct" power supply aren't exy either. No reason in fact a voltage monitoring relay couldn't be used to hook an array Direct for bulk charging into a bank and then just disconnect it at a set voltage and let a proper controller do the " Fine" charging and maintence work.



  Quote   and my old 100 series F&P NOT re-wired just wired in delta and using the same cap bank that guy from down south came to see then ripped off my idea.


I'd like to read more about that. Do you have anything about it here?
 
Haxby

Senior Member

Joined: 07/07/2008
Location: Australia
Posts: 188
Posted: 08:35pm 24 Nov 2020
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If I was to go off grid, I'd buy a full Nissan leaf pack from a company in South Australia here:

24kw lithium battery


And a CAN bus controller here:

Leaf Batt Controller



The CAN bus controller talks directly to the Nissan leaf pack BMS inside the battery enclosure, so you don't have to disassemble it. It's a 96 cell pack in series, so 360V nominal. The controller has relay outputs to start/stop charging, and reads out all cell voltages on the LCD.

The batt pack also has relays and precharge resistors that the can bus controller can control, as well as over current, so that makes battery management easy.


So with the Nissan leaf full pack, a CAN bus controller, a warpverter, and a standard AC coupled grid connect solar inverter system, you can build up an inexpensive off grid battery solution for a minimal cost. In the US, those leaf packs go for under $1000.

The CAN bus controller can control 2 Nissan leaf packs if you need double the storage.


Dual Battery support


The big question is "how reliable is the solution" and will it burn your house down or cause a bushfire!
 
Davo99
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Joined: 03/06/2019
Location: Australia
Posts: 727
Posted: 10:18pm 24 Nov 2020
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  Haxby said  If I was to go off grid, I'd buy a full Nissan leaf pack from a company in South Australia here:

24kw lithium battery


And a CAN bus controller here:

Leaf Batt Controller


What would be your motivation for going that way over say a LA forklift pack?  Obviously the leaf pack would be more compact and lighter ( although a lot heavier than I thought) But would seem that the LA pack offers a lot more capacity for the $$.

What are the advantages of the leaf pack to you that would make that the better choice for your needs?
Edited 2020-11-25 08:18 by Davo99
 
Haxby

Senior Member

Joined: 07/07/2008
Location: Australia
Posts: 188
Posted: 12:29am 25 Nov 2020
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No specific reason really. Lead acid is starting to seem archaic these days with so many Powerwall manufacturers choosing lithium. Each chemistry has its own benefits and drawbacks.
 
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