diy solar

diy solar

This guy claims lead acid is superior to Lithium Iron Phosphate in solar applications

Sorry, off topic, but the "build" itself is also important as it provides deep energy conservation which over the long term provides a far better return on investment. 45.9° N here.
HaHa! Is this something like mission creep? First you get a solar yard light and think its pretty neat. Then you get a plugin car and think, "man it would be cool to run this thing on solar". Next, you realize that you could run the whole house on solar. But its cold in winter, so pretty soon you're tearing the house apart and trying to make it meet passive house standards. :)

That would have to be a new forum topic all together. I don't think one exists for passive solar. Probably not where Will anticipated this going.
 
HaHa! Is this something like mission creep? First you get a solar yard light and think its pretty neat. Then you get a plugin car and think, "man it would be cool to run this thing on solar". Next, you realize that you could run the whole house on solar. But its cold in winter, so pretty soon you're tearing the house apart and trying to make it meet passive house standards. :)

That would have to be a new forum topic all together. I don't think one exists for passive solar. Probably not where Will anticipated this going.
Hahaha, that has happened to many here indeed. My own tomfoolery is by design from the ground up literally. Searched hi & lo to find the right land, cleared parts of the forest, designed & built for purpose. Even before building, I watched a full year (4 seasons) on the land to see where the winds favoured and how things "laid" before deciding on building placement etc. Much easier to work with Nature than combat it.
 
Other post was starting to get long but - The topic of recycling. The video thumbnails show PALLETS of batteries that are toast. How easy do you think it is to recycle a battery this big?

We are located in CALIFORNIA, A state that literally lives for recycling. I damn near have to PAY TO RECYCLE these batteries, the lead recyclers don't even want to mess with them because they are so large. These piles of batteries have been sitting out back for the last 2 years or so by now...It's sad to see $6400 sitting there rotting in the sun and rain, with nowhere to go. Sad day.

SO DON'T DO THIS AT HOME - I AM WHAT THEY CALL A TRAINED PROFESSIONAL ... :)

SOOOOO the guys from MOPAC (Missouri Pacific Railroad) asked us if they could store a few of their larger batteries at our HAZMAT site and our FNG engineer said sure - he probably should have asked some more questions though ...

SOOO after this 18 wheeler left after dumping this 52 foot container off full of batteries -- our FNG Engineer said that he had learned some cool tricks in Power School and wondered if we would mind him playing with these ... now understand - there are just normal lead acid batteries - like in your car - but 10X larger ....

so he popped the caps off all the batteries (they were maintenance free) and using a large trough he turned the battery upside down and all this acid and crap - lotta crap came out ...

he mixed up a solution of 1/2 distilled water and 1/2 distilled Epsom salt and poured it into the empty batteries ... and filled up each cavity. Then he took a 50A charger and connected it to the battery and turned it on and let it run until all the cells were bubbling ... he unplugged it -- put a turkey baster in a cell one at a time and squished around the solution in each cell really good -- basically flushing it -- and then poured out the Epson salt and even more crap... then he filtered all the solids out all the liquids (acid and water/salt) that was in the large plastic trough and refilled the battery -- capped it -- hit it again with a 50A charger for like 3 minutes -- then put a regular charger on these until they stopped charging .... holy cow -- he did like 15 of these that way and today they are still holding a charge at like 13.8 ... apparently there are lots of ways to get dead batteries back to life -- i just had never seen it done ...

But all day Thanksgiving I was watching these YouTube videos of ppl bringing batteries back to life - pretty cool

apparently the Epsom salt and the electricity causes the bad stuff to break up and fall off the copper cells ....

AGAIN - DON'T TRY THIS AT HOME -- I ACTUALLY DON'T GET IN TROUBLE FOR CATCHING THINGS ON FIRE -- YOU MIGHT...
 
So, His point Lithium batteries on calendar life vs cycle life certainly is interesting, we are off-grid so I wonder how many years our battery bank will last.

20 minutes is as far in as I made it. I can't last through the hour long video :(
 
SO DON'T DO THIS AT HOME - I AM WHAT THEY CALL A TRAINED PROFESSIONAL ... :)

SOOOOO the guys from MOPAC (Missouri Pacific Railroad) asked us if they could store a few of their larger batteries at our HAZMAT site and our FNG engineer said sure - he probably should have asked some more questions though ...

SOOO after this 18 wheeler left after dumping this 52 foot container off full of batteries -- our FNG Engineer said that he had learned some cool tricks in Power School and wondered if we would mind him playing with these ... now understand - there are just normal lead acid batteries - like in your car - but 10X larger ....

so he popped the caps off all the batteries (they were maintenance free) and using a large trough he turned the battery upside down and all this acid and crap - lotta crap came out ...

he mixed up a solution of 1/2 distilled water and 1/2 distilled Epsom salt and poured it into the empty batteries ... and filled up each cavity. Then he took a 50A charger and connected it to the battery and turned it on and let it run until all the cells were bubbling ... he unplugged it -- put a turkey baster in a cell one at a time and squished around the solution in each cell really good -- basically flushing it -- and then poured out the Epson salt and even more crap... then he filtered all the solids out all the liquids (acid and water/salt) that was in the large plastic trough and refilled the battery -- capped it -- hit it again with a 50A charger for like 3 minutes -- then put a regular charger on these until they stopped charging .... holy cow -- he did like 15 of these that way and today they are still holding a charge at like 13.8 ... apparently there are lots of ways to get dead batteries back to life -- i just had never seen it done ...

But all day Thanksgiving I was watching these YouTube videos of ppl bringing batteries back to life - pretty cool

apparently the Epsom salt and the electricity causes the bad stuff to break up and fall off the copper cells ....

AGAIN - DON'T TRY THIS AT HOME -- I ACTUALLY DON'T GET IN TROUBLE FOR CATCHING THINGS ON FIRE -- YOU MIGHT...

Really? You're going with this? I thought you were data driven as an engineer. :)

Was any testing done to confirm that these batteries are actually any good or meet anything close to rated capacity? You can have a crapton of yuck in the bottom of the battery, and as long as it doesn't short out the plates, it hardly matters if it's there or not.

Holding voltage doesn't equate to "good battery." A 1000Ah battery that has degraded to 1Ah of usable capacity will hold voltage as well as a 10000Ah battery provided all the cells are at 100% SoC.

Also, the resulting solution from Epsom salt treatment results in a higher voltage.

I have NEVER seen anyone do any testing besides a voltmeter, and "Yup! Car starts!". Conduct some sort of meaningful testing and impress us.

:) :) :) <- to try and soften the tone... :)
 
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Really? You're going with this? I thought you were data driven as an engineer. :)

Was any testing done to confirm that these batteries are actually any good or meet anything close to rated capacity? You can have a crapton of yuck in the bottom of the battery, and as long as it doesn't short out the plates, it hardly matters if it's there or not.

Holding volt doesn't equate to "good battery." A 1000Ah battery that has degraded to 1Ah of usable capacity will hold voltage as well as a 10000Ah battery provided all the cells are at 100% SoC.

Also, the resulting solution from Epsom salt treatment results in a higher voltage.

I have NEVER seen anyone do any testing besides a voltmeter, and "Yup! Car starts!". Conduct some sort of meaningful testing and impress us.

I'm going to put you down in the "Skeptic" column on this.
thud.gif
 
SO DON'T DO THIS AT HOME - I AM WHAT THEY CALL A TRAINED PROFESSIONAL ... :)
he turned the battery upside down and all this acid and crap - lotta crap came out ...
This "crap" contains actually a lot of highly environmentally hazardous lead and not less nocive sulphuric acid.
Lead Acid batteries MUST be recycled by professionals, and excepted the doing of a few idiots, they are one of the best recycled stuff ever.
 
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So, I watched the entire second video. Near the beginning, he does acknowledge that lead acid batteries require careful operation and regular maintenance if one is going to get the maximum rated life from them. Then he also acknowledges that lithium batteries can endure much longer spans without attention if operated within their limits. He must have gotten hammered in the comments.

But then, by the end of the video, he seems to have forgotten all the stuff he said about lead acid when he starts talking about how the BMS in a lithium battery will inevitably fail and kill the battery. Sure, that can and does happen, but I'm not convinced that a BMS failure is more likely than a human failure to properly maintain lead acid.

He makes a decent point about the lack of data on calendar life with LiFePO4. In my comparisons, I've never assumed longer than a 10 year calendar life because I've seen the degradation curve charts he included in his video. Once the claimed cycle life stretched out past 10 years of calendar time, the extra cycles don't matter, so to me it makes no sense spend additional money so that you can baby your LiFePO4 batteries with the hope of getting 5000 cycles instead of 3500.

The other thing that surprised me is that he selected the lead acid battery with the lower life as the better choice (it is cheaper also, though). So I looked up the battery manual for the NSB100 Blue+ battery. This battery does make some sense for solar in that it is a thin plate battery with relatively low internal resistance and good charge rates. It can produce its rated capacity at a C8 discharge rate. It still suffers from 50% capacity loss at low temperatures and the need to maintain 50% charge at low temperatures to prevent freezing, so 25% usable capacity

He says he is biasing his comparison in favor of lithium by virtue of the operational requirements of his proposed system. However, he makes the same mistakes in this video as he did in the last. He doesn't use the lithium batteries to 90% of discharge, even though that use pattern still allows for a 10 year life span. He also gives the NSB100 Blue+ battery its full life span, which requires temperature controlled operation, and optimal discharge-charge patterns. Below are the relevant quotes from the manual:

For example, if the temperature rises from the
recommended operating temperature of +25°C, to
+45°C, the expected life of the monobloc will decrease
from 10 to 2 years
So both chemistries like to operate at 25°C (77° F). The difference is that the manual says cooling has to be provided for the NSB100 Blue+ if you charge them at high rates. The LiFePO4 batteries generate much less heat during the charge cycle.

Blue+ batteries are designed to be able to operate in
highly cyclic applications as well as PSOC applications.
During optimal PSOC charging regime, NSB Blue+
batteries can be expected to achieve cycle life according
to image.VVXZU0.pngthe chart below.
This chart to me was the killer, because you have to achieve "Optimal" charge conditions to get the 50% depth of discharge 2000 cycle life he is using in his comparison. If that is the most commonly achieved regimen, why is the other one called "Standard". Standard cuts the cycle life to 1000, which is just under three years. This is probably the life that most people are likely to achieve. Near as I could discern from the manual, Optimal requires specific charge rates depending upon depth of discharge and a 16 hour equalization phase every two weeks. I just don't think that is realistic for most residential solar applications. (I tried looking for the warranty, or the warranty disclaimers because they often spell out the limits of the battery better than the instructions, but I couldn't locate either on the manufacturer website)

Anyway, once again, I'm not saying that no one should use lead acid. What I am saying is that this video doesn't do a good job of representing outcomes under real world conditions. People should pick what works for their budget and system based on data representative of their operating conditions.

Anyway, enough on this from me. Cheers!
 
SO DON'T DO THIS AT HOME - I AM WHAT THEY CALL A TRAINED PROFESSIONAL ... :)

This "crap" contains actually a lot of highly environmentally hazardous lead and not less nocive sulphuric acid.
Lead Acid batteries MUST be recycled by professionals, and excepted the doing of a few idiots, they are one of the best recycled stuff ever.
Pfffff.... Apparently you have not seen where I work ... we use nocive sulphuric acid to wash our hands before breakfast ... and then spray it on our wrists to smell pretty ...
 
Really? You're going with this? I thought you were data driven as an engineer. :)

Was any testing done to confirm that these batteries are actually any good or meet anything close to rated capacity? You can have a crapton of yuck in the bottom of the battery, and as long as it doesn't short out the plates, it hardly matters if it's there or not.

Holding voltage doesn't equate to "good battery." A 1000Ah battery that has degraded to 1Ah of usable capacity will hold voltage as well as a 10000Ah battery provided all the cells are at 100% SoC.

Also, the resulting solution from Epsom salt treatment results in a higher voltage.

I have NEVER seen anyone do any testing besides a voltmeter, and "Yup! Car starts!". Conduct some sort of meaningful testing and impress us.

:) :) :) <- to try and soften the tone... :)

Look - pretend your out n the middle of Texas -- the only entertainment you have is NETFLIX and YouTube -- there are NO FM stations and the only AM station you can pick up is a Mexican religious station ... we do have XM radio so I guess thats not too bad ... but unless there is a fire - our someone gets drunk and steals a fuel truck -- the boredom level is pretty damn high .... so when a FNG engineer shows up and says "hey I can do this or that" we normally get a 12 pack of beer and our lawnchairs - and a huge ABC Fire extinguisher - and tell him "Let the entertainment begin" ...

So YES technically if I am wearing my EE hat YES he could have had 13.8 volts and literally 0.01A ... but these weren't my batteries ... and I had never seen anyone do that trick of bringing batteries back to life like that -- and in the morning after shift i will drop a load on one of them and see what kind of aH I get ... but more importantly --did I mention the complete boredom ...
 
lead acid ... It still suffers from 50% capacity loss at low temperatures and the need to maintain 50% charge at low temperatures to prevent freezing, so 25% usable capacity

Is that correct?

Or if I have a 100Ah battery, I shouldn't discharge more than 50Ah from it in cold climate because it could freeze. But if cold when I discharge it, 50 Ah is all I'm going to get anyway before voltage drops too low? So 50% usable?

And does it really stop delivering electrons after 50 Ah? Or does it just do so at lower voltage?


Near as I could discern from the manual, Optimal requires specific charge rates depending upon depth of discharge and a 16 hour equalization phase every two weeks. I just don't think that is realistic for most residential solar applications. (I tried looking for the warranty, or the warranty disclaimers because they often spell out the limits of the battery better than the instructions, but I couldn't locate either on the manufacturer website)

What's wrong with that? I can program my inverter/charger to equalize on any schedule and for any duration I wish. Can't you?
As for rate, I can set one rate. It will get that all day long.
 
Is that correct?

Or if I have a 100Ah battery, I shouldn't discharge more than 50Ah from it in cold climate because it could freeze. But if cold when I discharge it, 50 Ah is all I'm going to get anyway before voltage drops too low? So 50% usable?

And does it really stop delivering electrons after 50 Ah? Or does it just do so at lower voltage?
Valid question. My interpretation was based on the two things being stated separately in the manual. (it should be noted that the 50% loss of capacity wasn't until -40° C. At -20° C the loss was only 25%.) The state of charge was to be determined by voltage. Maybe I'm interpreting this wrong. Its probably irrelevant anyway because if you are optimizing performance, you never go below 50% state of charge even when the temperatures are warm.
What's wrong with that? I can program my inverter/charger to equalize on any schedule and for any duration I wish. Can't you?
As for rate, I can set one rate. It will get that all day long.
My comments are particularly directed to off grid operation. If you have grid connection and they are just backup batteries, you can get the optimal advertised life because you can properly care for them. In off grid applications, most people are energy poor part of the year and have to really stress their storage system. That's why this omission from the evaluation in the video was relevant.
 
Valid question. My interpretation was based on the two things being stated separately in the manual. (it should be noted that the 50% loss of capacity wasn't until -40° C. At -20° C the loss was only 25%.) The state of charge was to be determined by voltage. Maybe I'm interpreting this wrong. Its probably irrelevant anyway because if you are optimizing performance, you never go below 50% state of charge even when the temperatures are warm.
The "loss of capacity" is only temporary. It just means, that at low temperatures the chemical processes are slower. You just cannot push and pull as much energy as you could with a warmer battery. As soon as the battery regains temperature, the energy stored will be available again.
(By comparison and with the same criteria, a LiFePo has a 100% loss of capacity under 0°C, you should not charge it at all!)
Under real operation at latitudes > 50°, you should design your off grid system to be able to operate long time without energy income anyhow. That means design it for discharge rates far lower than C/100. Unless you live at high altitudes or in polar regions your thermically insulated battery will not drip under critical temperatures. Currently, I just do not know any chemistry that it's better able to deal with low temperatures than lead-acid.
 
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What's wrong with that? I can program my inverter/charger to equalize on any schedule and for any duration I wish. Can't you?
As for rate, I can set one rate. It will get that all day long.
Off-grid, during wintertime you mainly cannot. You can feel lucky if you get a sunny day to try to regain some charge level, and if you really get the perfect week of 7 consecutive sunny days, hope to be able to equalize for a couple of hours.
 
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The "loss of capacity" is only temporary. It just means, that at low temperatures the chemical processes are slower. You just cannot push and pull as much energy as you could with a warmer battery. As soon as the battery regains temperature, the energy stored will be available again.
(By comparison and with the same criteria, a LiFePo has a 100% loss of capacity under 0°C, you should not load it at all!)
Certainly understood that the loss of capacity is temporary. Lead acid is more likely to sustain damage at high temperatures, not low temperatures.

However, the statement about LiFePO4 is not correct. You can discharge it below freezing, but unless specially designed you cannot charge it below freezing. For other people doing battery comparisons, I clipped the discharge table from the EVE 280 ah datasheet. I don't think most people realize how severely the discharge rate on LiFePO4 is limited at low states of charge and low temperatures.
1606636233088.png
 
I also ran across this guy's videos on trying to recover damaged lead acid batteries. Its kind of instructive on what can be done with a bad lead acid battery but also shows how much time and energy it can take.

 
However, the statement about LiFePO4 is not correct. You can discharge it below freezing, but unless specially designed you cannot charge it below freezing. For other people doing battery comparisons, I clipped the discharge table from the EVE 280 ah datasheet. I don't think most people realize how severely the discharge rate on LiFePO4 is limited at low states of charge and low temperatures.
yes, I corrected my statement, obviously I meant you should not charge it at all.
And thank you very much for the table, I just wanted to upload a similar table as well.
That is really a deal changer for all those LiFePo advocates trying to promote their "ideal" chemistry for low temperatures. :p
If you compare the temperature impact at low temperatures, lead-acid wins thumbs up.

And regarding the "special design" of LiFePo capable of charging as low as -20°C, have you taken a closer look at it?
They just have added a circuit to dissipate the input energy to heat up the battery before enabling the loading process: don't come and tell me about the efficiency!
:eek:
 
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