chrisski
Solar Boondocker
- Joined
- Aug 14, 2020
- Messages
- 5,189
I must have missed that thread. In this one I see a Lithium batteries, which I agree you can mix and match because of low internal resistance, but not lead batteries.
Extending a part worn battery bank
- Thread starter Willbiker
- Start date
Dude, if I can just "read it anywhere", then you should have no problem posting something that says that, especially since it's supposedly everywhere.
Old wives tale.
Nobody is leading anything. Just post links or data. Then it would be "leading a horse to water". But nobody can actually post anything because it doesn't exist.
I don't need Google to tell me my data is correct. If you feel it's wrong, then the burden is on you to show contradictory data. An engineering degree is more my friend than Google.
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Complete Guide On How To Charge A Lead Acid Battery - Power Sonic
Power Sonic's guide on how to charge a lead acid battery includes charging methods, characteristics & how to charge in series and parallel
www.power-sonic.com
"Connecting batteries of different amp hour capacities in parallel"
By the way, I'm not just a "redneck engineer". I'm an ACTUAL engineer.Attachments
boondox
Chief Engineer, RedNeckTech Industries
- Joined
- Mar 1, 2020
- Messages
- 788
Yer killing me.
What you link is information about charging batteries. It is very basic information for charging SLA's. It makes no reference to charging batteries of different ages. It does mention parallel charging of batteries of unequal capacity. This is not what we are talking about. It is hardly any sort of proof that mixing batteries of different ages will have no effect on the new batteries.
You have yet to produce your oft quoted "research". You make claims and don't back them up. What you say disagrees with what the lead battery industry believes. Remarkable claims require remarkable proof. So let's see it. If you have it, I am willing to learn. But simply making claims is not going to get it done.
Neither is posting a picture of what may or may not be your degree. I have known many with degrees that knew nothing. And many without a degree who were incredibly knowledgeable. Certainly swaggering your degree means nothing to me. Nor does your dig at "redneck engineering". Both of these things only lower the likelihood that you have anything to offer.
What you link is information about charging batteries. It is very basic information for charging SLA's. It makes no reference to charging batteries of different ages. It does mention parallel charging of batteries of unequal capacity. This is not what we are talking about. It is hardly any sort of proof that mixing batteries of different ages will have no effect on the new batteries.
You have yet to produce your oft quoted "research". You make claims and don't back them up. What you say disagrees with what the lead battery industry believes. Remarkable claims require remarkable proof. So let's see it. If you have it, I am willing to learn. But simply making claims is not going to get it done.
Neither is posting a picture of what may or may not be your degree. I have known many with degrees that knew nothing. And many without a degree who were incredibly knowledgeable. Certainly swaggering your degree means nothing to me. Nor does your dig at "redneck engineering". Both of these things only lower the likelihood that you have anything to offer.
Yer killing me. You need to read it. It talks about parallel lead acid.
My research wasn't part of an academic institution and isn't "published". It's something I did just for myself.
YOU haven't posted anything that backs up your claim, which you should be able to do since supposedly it has been known for 100's of years. So now that we know my work hasn't been published, how about you post what you say is common knowledge.
And it figures that you'd have a problem with me posting my DRIVER'S LICENSE with the degree and have the nerve to say "may not be your degree". Now I understand the type of person I'm dealing with and have no desire to waste my time. You do you. I don't care what you do or don't do with your batteries. It won't change my life. I was just trying educate you. Stay ignorant if you want.
boondox
Chief Engineer, RedNeckTech Industries
- Joined
- Mar 1, 2020
- Messages
- 788
Oh, I am open to learning. I made that clear. But you aren't providing any sort of proof. I never claimed to have done research with proper controls, but you did. Even if you didn't publish papers, giving us the details on your experiments could give you credibility. But we'd have to hear the details.
The link above has exactly two paragraphs on parallel charging. It in no way references batteries of different ages. I couldn't care less if that is your degree or not. It is hilarious you think I have "the nerve" to question your degree. This is the internet my friend. Anyone can claim anything. I made a spaceship and went to the moon!
Even if it is your degree, a degree is no proof of knowing what you are talking about. And in this case, you are wrong. Many, many people have seen first hand the effects on mixing new lead batteries with old. Call Crown and Surrette and see what they say. I'm sure you know more than they do.
The link above has exactly two paragraphs on parallel charging. It in no way references batteries of different ages. I couldn't care less if that is your degree or not. It is hilarious you think I have "the nerve" to question your degree. This is the internet my friend. Anyone can claim anything. I made a spaceship and went to the moon!
Even if it is your degree, a degree is no proof of knowing what you are talking about. And in this case, you are wrong. Many, many people have seen first hand the effects on mixing new lead batteries with old. Call Crown and Surrette and see what they say. I'm sure you know more than they do.
Yeah, it's the Internet. That's why I posted my driver's license which matches the name on the degree and even matches my username.
No, many people HAVE NOT seen the effects first hand of mixing PARALLEL CELLS new and old and have a rapid adverse outcome. Batteries get old. It's going to happen whether parallel cells or not. But when you DO parallel cells and they eventually get old and die, it wasn't the paralleling that did it. Simply cycling them is what did it, parallel or not. People no doubt have tried using new and old cells in series and had problems very quickly show up. But I'm strictly speaking of parallel cells only.
So am I.
What does that even mean? Do you have anything intelligent to add? Better yet, post a link to a manufacturer's document or ANYTHING that even remotely suggests what you think your understanding is. You won't find it since it doesn't exist. This is the problem when someone challenges a LONG HELD belief that people have just blindly accepted as gospel without really understanding it for themselves.
Back in engineering school I debunked that old wives tale that says you can tell how far away lighting was by counting how many seconds pass until you hear the thunder (supposedly 1 second per mile distance). I proved it was wrong and that the lightning was actually CLOSER by a large margin. Other academics furiously resisted my results and refused to believe it. THAT one I actually did publish and everyone had to accept it that it was scientifically accurate.
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boondox
Chief Engineer, RedNeckTech Industries
- Joined
- Mar 1, 2020
- Messages
- 788
Well, of course in at least one sense almost all batteries are in series, except for 1.5 volt cells. What I have seen cause issues however is 6 volt batteries in series/parallel to form large 12 volt banks. In general when one 6V battery goes bad the other in series will quickly follow. I have replaced one (really quick problems) and both in the string. In either case, in short order the battery will not charge above what the others in the array are, as measured with a hydrometer. Removing the batteries from the bank and charging them separately they still would not charge fully. Even an EQ charge won't remedy it. So they had been degraded by being in parallel with the other batteries. Remember, this happened when both batteries in series were replaced. I have seen the same thing when 12V batteries were used to form the bank.
I very much agree that inserting a new battery in series with old ones is a quick recipe for trouble. But parallel use will too, just not as drastically as series. I have seen this on multiple occasions back in the day when we all ran large banks of 6V FLAs to form large banks of 12V. Back then 12V inverters were all that was available and the banks were very large parallel arrays. I admit the data is fuzzy because there are other factors at play. Asymmetrical connections, unequal cable lengths, some connections not as good as others are all influencing pack aging. Nonetheless, I have seen batteries sink to the lowest common denominator within a couple of months and be unable to charge fully. Even within a couple of weeks they will read the same as the rest of the bank but will still fully charge if taken out of the bank. I have been living on FLAs for over 20 years and have helped many people with their off grid systems and have worked with many battery banks.
And really, do call Crown or Surrette. I guarantee they will tell you it is not a good idea. None of the reputable solar installers I know recommend replacing weak cells with new ones. Personally my rule of thumb is put a load test on the used but good batteries and if they test above 80% it is worth it to put a new battery in it. If not, just lower the cut out voltage if needed and keep beating on the bank until it is dead, then replace the entire thing.
I very much agree that inserting a new battery in series with old ones is a quick recipe for trouble. But parallel use will too, just not as drastically as series. I have seen this on multiple occasions back in the day when we all ran large banks of 6V FLAs to form large banks of 12V. Back then 12V inverters were all that was available and the banks were very large parallel arrays. I admit the data is fuzzy because there are other factors at play. Asymmetrical connections, unequal cable lengths, some connections not as good as others are all influencing pack aging. Nonetheless, I have seen batteries sink to the lowest common denominator within a couple of months and be unable to charge fully. Even within a couple of weeks they will read the same as the rest of the bank but will still fully charge if taken out of the bank. I have been living on FLAs for over 20 years and have helped many people with their off grid systems and have worked with many battery banks.
And really, do call Crown or Surrette. I guarantee they will tell you it is not a good idea. None of the reputable solar installers I know recommend replacing weak cells with new ones. Personally my rule of thumb is put a load test on the used but good batteries and if they test above 80% it is worth it to put a new battery in it. If not, just lower the cut out voltage if needed and keep beating on the bank until it is dead, then replace the entire thing.
So I'm here to set everyone on a body of water? I guess you don't have anything intelligent to add. That answers that question.
