diy solar

diy solar

Doubt about lifepo4 and float .

vallesj said:
I don't think the growatt has option to see current going or coming from battery... And the battery monitor it has current monitoring included, not shunt but a Hall effect sensor. But I think the topic or concerning is not about the SOC, but the voltage setting for bulk. Anyways, my panels produce max of 1200w, meaning the max current my battery could get is 20A (1200w/58.4v), very low of the normal 25A recommended by maker, or the 50A indicated as max charging current. Probably as @Suijkerbuijk said, the growatt is acting based on float which I set as 54v.
View attachment 223428
This is the graph from yesterday, no loads, just set to charge with Solar (saving battery in case is needed with current storm warnings in south Texas). It behaves similar to the power generated by the panels. I would expect the voltage remains at 54, but it drops relatively fast back to the ~53.4v mark.
View attachment 223431 So I am thinking that it is the limit the ecoworthy batteries BMS have for considering fully charged. By the way, I started with just one 48v 50ah battery back in May, and a week ago I installed the second one, so behavior is similar.
Click to expand...
I am not sure you understand what I was saying . The bms is programmed to cut off charging either at high voltage to protect battery pack , or if one or more cells in it gets too high. Without knowing if he battery is taking in current or not , it would be hard to know what the bms is doing. Zero current going into battery means that the charging has been cut off for whatever reason. Voltage can't really tell you much
 
BarracudaBob said:
I have no complaints but if you asked me if I would do it again it would depend. The Eco-Worthy 12V 100aH were purchased for electronics on boat, camping, and ham radio. I even have one of the 30ah for a DIY stereo for back yard. Zero issues. I took one with a harbor freight 2k inverter and wife used it on a 120Vac pole saw. So for portable 12V applications they worked great for the price.

Then in entered the world of EG4 Rack mount batteries. I incorporated the 4 EW 12V100A into those batteries and had one of their monitors to watch the EW 48V SOC. Again Zero issues playing nice-nice with EG4 LiFePower4.

Now moving to the future I added 2 more rack batteries to the cabinet. I have the EW batteries roller not being used. I don't like the exposed terminals and looking for a box to take the cells out and put under one BMS. Unfortunately they will never talk to the EG4 via Solar Assistant.

I like the 48v metal box and reviews of the DCHouse BUT no Bluetooth or info coming out of the box. Only 50lbs vs over 100 lb of a EG4. You can't beet the price of the DCHouse & Eco-Worthy. I want more out of my system so I would rather a more advance battery. After 1-1/2 years I have had Zero issues or complaints. They all charged up to 56.4V and always worked.

I have had more issues with the EG4 than the ECO-Worthy.

(old picture of me testing things, kind of messy)
View attachment 223528
Click to expand...
Thank you so much for the photos and what you wrote. Considering the price of the dchouse I would like to at least try with one. I currently use my glorious 110 amp AGM batteries, which as you know I use at 50-60% of their capacity. Normally, I have a constant consumption of 80 watts x 24H and even in winter I managed to manage them. During the day in the summer period, having 1.5 kwp of panels and a 3000/6000 pure inverter, I keep the refrigerator turned on, 5 cameras, a mini PC and fans, TV etc. In the evening at the cut off I find myself with a voltage on the batteries of just under 51 v, and thanks to the homeassistant programming I turn off the fridge until the battery threshold reaches 49.20 v and then arrive in the morning with 48, 30v or sometimes as low as 47.40v. I think that if I were to buy the Lifepo4, compared to the AGM they take the maximum charge even up to 100%, which unfortunately the AGM does not do for the last 30% of charge!
 
Lardino said:
I am not sure you understand what I was saying . The bms is programmed to cut off charging either at high voltage to protect battery pack , or if one or more cells in it gets too high. Without knowing if he battery is taking in current or not , it would be hard to know what the bms is doing. Zero current going into battery means that the charging has been cut off for whatever reason. Voltage can't really tell you much
Click to expand...
That is exactly why I like to remote monitor everything and prefer a more advance battery. Here is an example of the BMS showing that one battery disconnected. It has a lower INTERNAL voltage than the rest. Caused by one cell over voltage shutting down the BMS. Without the internal reading the only way would be to measure the current going into each battery. (same thing you said)
1718979167407.png
 
BarracudaBob said:
I have no complaints but if you asked me if I would do it again it would depend. The Eco-Worthy 12V 100aH were purchased for electronics on boat, camping, and ham radio. I even have one of the 30ah for a DIY stereo for back yard. Zero issues. I took one with a harbor freight 2k inverter and wife used it on a 120Vac pole saw. So for portable 12V applications they worked great for the price.

Then in entered the world of EG4 Rack mount batteries. I incorporated the 4 EW 12V100A into those batteries and had one of their monitors to watch the EW 48V SOC. Again Zero issues playing nice-nice with EG4 LiFePower4.

Now moving to the future I added 2 more rack batteries to the cabinet. I have the EW batteries not being used. I don't like the exposed terminals and looking for a box to take the cells out and put under one BMS. Unfortunately they will never talk to the EG4 via Solar Assistant.

I like the 48v metal box and reviews of the DCHouse BUT no Bluetooth or info coming out of the box. Only 50lbs vs over 100 lb of a EG4. You can't beet the price of the DCHouse & Eco-Worthy. I want more out of my system so I would rather a more advance battery. After 1-1/2 years I have had Zero issues or complaints. They all charged up to 56.4V and always worked.

I have had more issues with the EG4 than the ECO-Worthy.

(old picture of me testing things, kind of messy)
View attachment 223537
Click to expand...
Excellent, your storage sounds good so 48v 100 amps. I had thought about 100 amp redodo batteries in series, but everyone advises against purchasing them due to possible BMS and balancing problems. I see that your racks are set up to work at least I believe in master and slave.
 
frankz66 said:
Thank you so much for the photos and what you wrote. Considering the price of the dchouse I would like to at least try with one. I currently use my glorious 110 amp AGM batteries, which as you know I use at 50-60% of their capacity. Normally, I have a constant consumption of 80 watts x 24H and even in winter I managed to manage them. During the day in the summer period, having 1.5 kwp of panels and a 3000/6000 pure inverter, I keep the refrigerator turned on, 5 cameras, a mini PC and fans, TV etc. In the evening at the cut off I find myself with a voltage on the batteries of just under 51 v, and thanks to the homeassistant programming I turn off the fridge until the battery threshold reaches 49.20 v and then arrive in the morning with 48, 30v or sometimes as low as 47.40v. I think that if I were to buy the Lifepo4, compared to the AGM they take the maximum charge even up to 100%, which unfortunately the AGM does not do for the last 30% of charge!
Click to expand...
I have found that you need to USE these batteries. Take them down to 20% and up to 56.4 or as they say 58V (OMG) to get them to balance out. They want to be used and have a little TLC. Worst case you can open them up an charge each cell to 3.650 (absolute max) and bring them back to life. The fact you can take the cover off you can add BMS, Meters, and play with it. My plastic sealed ones don't allow me to do that.
 
frankz66 said:
Thank you so much for the photos and what you wrote. Considering the price of the dchouse I would like to at least try with one. I currently use my glorious 110 amp AGM batteries, which as you know I use at 50-60% of their capacity. Normally, I have a constant consumption of 80 watts x 24H and even in winter I managed to manage them. During the day in the summer period, having 1.5 kwp of panels and a 3000/6000 pure inverter, I keep the refrigerator turned on, 5 cameras, a mini PC and fans, TV etc. In the evening at the cut off I find myself with a voltage on the batteries of just under 51 v, and thanks to the homeassistant programming I turn off the fridge until the battery threshold reaches 49.20 v and then arrive in the morning with 48, 30v or sometimes as low as 47.40v. I think that if I were to buy the Lifepo4, compared to the AGM they take the maximum charge even up to 100%, which unfortunately the AGM does not do for the last 30% of charge!
Click to expand...
Here is the "Yard Box", we have run vacuum pumps for HVAC, pole saws, and pellet grill's of this bad boy. AMZ box with a SOC/Volt meter attached.
1718980082964.jpeg
 
Lardino said:
I am not sure you understand what I was saying . The bms is programmed to cut off charging either at high voltage to protect battery pack , or if one or more cells in it gets too high. Without knowing if he battery is taking in current or not , it would be hard to know what the bms is doing. Zero current going into battery means that the charging has been cut off for whatever reason. Voltage can't really tell you much
Click to expand...
If the bms shutdown you still can use Multimeter to see what volt are there. (My do)
If i set discharge and charge of manuel by the Bluetooth option from the bms
I still can test the volts of the battery.
But if i set a light bult on it it will not go on.
And nothing will charge by the charger
 
frankz66 said:
Can you explain it to me better?
Click to expand...
There are 16 cells in a 48V battery. If one of them get to high and others get to low in voltage the "Pac" becomes unbalanced. When you charge them up one cell will go into over voltage and the BMS will disconnect the PAC from the outside terminals until the BMS bleads down the top cell. The bottom ones never reach the upper voltage you are are stuck in an unbalanced situation. The internal battery PAC voltage never goes up to where it is supposed to and you don't get a full charge SOC=100%. By taking them down and back up a couple of times this usually will balance them out. I found for my self that Float of 54.4 (54.0 to 54.4 range) and a Bulk/Absorb of (56.2-56.4) keeps my PAC's happy. There are graphs and charts and better explanations than that but that is my short answer.
 
BarracudaBob said:
There are 16 cells in a 48V battery. If one of them get to high and others get to low in voltage the "Pac" becomes unbalanced. When you charge them up one cell will go into over voltage and the BMS will disconnect the PAC from the outside terminals until the BMS bleads down the top cell. The bottom ones never reach the upper voltage you are are stuck in an unbalanced situation. The internal battery PAC voltage never goes up to where it is supposed to and you don't get a full charge SOC=100%. By taking them down and back up a couple of times this usually will balance them out. I found for my self that Float of 54.4 (54.0 to 54.4 range) and a Bulk/Absorb of (56.2-56.4) keeps my PAC's happy. There are graphs and charts and better explanations than that but that is my short answer.
Click to expand...
I finally understood. So what you personally experienced is explained by a fairly well-known YouTuber on float and bulk and their relative balance to some tensions. If you wish, look at the link, although in Italian but it illustrates the imbalance
 
frankz66 said:
I finally understood. So what you personally experienced is explained by a fairly well-known YouTuber on float and bulk and their relative balance to some tensions. If you wish, look at the link, although in Italian but it illustrates the imbalance
Click to expand...
Check out https://www.youtube.com/@WillProwse and https://www.youtube.com/@OffGridGarageAustralia
They will convince you to spend a lot of money trying all these cool things! So many toys and so little time (and money)
Enjoy!
 
BarracudaBob said:
Check out https://www.youtube.com/@WillProwse and https://www.youtube.com/@OffGridGarageAustralia
They will convince you to spend a lot of money trying all these cool things! So many toys and so little time (and money)
Enjoy!
Click to expand...
Thanks Bob, I follow Will on YouTube and I find the content of what he publishes very interesting and competent, at least as far as I can truly experience. What matters to me... is the English language! I should go to school to learn and take a good English course...
 
Oh man! This is getting me a headache. It should be simpler and cheaper if there are not so many restrictions on grid tie systems with electric companies. My setup was working fine when on SUB, no batteries needed or minimal for short momentarily blackouts, until I got the visit from the utility guy about a non authorized feedback. I had to invest more to make my system works so I bought the best priced batteries that currently nobody can beat: the Ecoworthy $400 per 48V@50ah. This none linear behavior on these chemistry related to voltage created some uncertainty if those are working as supposed or they are just garbage. But well, my main purpose to save money with solar optimizing costs is making me scratching my head: so many different recommendations about charging voltages, floating, etc... I guess I would settle this to SOL (only when sun is available and enough battery) 55.2 bulk, 53.6 floating.. low dc cut off at 43.2v.. voltage point back to utility source as 48v and voltage point back to battery/PV to 53.6, same as floating. Based on offgrid youtube videos, probably those will be the optimal balance on enough charging and life of the batteries. The main point is to have electricity to reduce my bill, with the least possible investment, or best ROI. I don't need fancy information from batteries, BMS... I want something simpler, reliable, not expensive, just a system that I set and forget.. probably periodically connect to the app and see how much money I saved that day... I don't need to be an expert on making battery systems for that.
 
vallesj said:
Oh man! This is getting me a headache. It should be simpler and cheaper if there are not so many restrictions on grid tie systems with electric companies. My setup was working fine when on SUB, no batteries needed or minimal for short momentarily blackouts, until I got the visit from the utility guy about a non authorized feedback. I had to invest more to make my system works so I bought the best priced batteries that currently nobody can beat: the Ecoworthy $400 per 48V@50ah. This none linear behavior on these chemistry related to voltage created some uncertainty if those are working as supposed or they are just garbage. But well, my main purpose to save money with solar optimizing costs is making me scratching my head: so many different recommendations about charging voltages, floating, etc... I guess I would settle this to SOL (only when sun is available and enough battery) 55.2 bulk, 53.6 floating.. low dc cut off at 43.2v.. voltage point back to utility source as 48v and voltage point back to battery/PV to 53.6, same as floating. Based on offgrid youtube videos, probably those will be the optimal balance on enough charging and life of the batteries. The main point is to have electricity to reduce my bill, with the least possible investment, or best ROI. I don't need fancy information from batteries, BMS... I want something simpler, reliable, not expensive, just a system that I set and forget.. probably periodically connect to the app and see how much money I saved that day... I don't need to be an expert on making battery systems for that.
Click to expand...


I think the Hysolis is probably the closest 'set and forget' appliance...IIRC it even self-charges once the sun comes back up.
 
vallesj said:
Oh man! This is getting me a headache. It should be simpler and cheaper if there are not so many restrictions on grid tie systems with electric companies. My setup was working fine when on SUB, no batteries needed or minimal for short momentarily blackouts, until I got the visit from the utility guy about a non authorized feedback. I had to invest more to make my system works so I bought the best priced batteries that currently nobody can beat: the Ecoworthy $400 per 48V@50ah. This none linear behavior on these chemistry related to voltage created some uncertainty if those are working as supposed or they are just garbage. But well, my main purpose to save money with solar optimizing costs is making me scratching my head: so many different recommendations about charging voltages, floating, etc... I guess I would settle this to SOL (only when sun is available and enough battery) 55.2 bulk, 53.6 floating.. low dc cut off at 43.2v.. voltage point back to utility source as 48v and voltage point back to battery/PV to 53.6, same as floating. Based on offgrid youtube videos, probably those will be the optimal balance on enough charging and life of the batteries. The main point is to have electricity to reduce my bill, with the least possible investment, or best ROI. I don't need fancy information from batteries, BMS... I want something simpler, reliable, not expensive, just a system that I set and forget.. probably periodically connect to the app and see how much money I saved that day... I don't need to be an expert on making battery systems for that.
Click to expand...
Realize you have all of knowledge and experience here to overload your brain. We thrive on complexity.

Here is some very conservatives voltages for you: https://off-grid-garage.com/my-settings/
 
cs1234 said:
Are they not the exact same thing with a different name on them? I can't even tell.
Click to expand...

I've been researching them, and info is sparse...Eco-Worthy panels I scored recently (200W bifacial) shipped from SoCal, but say Made in Canada (Canadian Solar?) so there is a link between Canadian Solar and Eco-Worthy. Several YT vids show Eco-Worthy has it's name and website directly on the included literature in the DC House battery's boxes, showing a direct link between Eco-Worthy and DC House. DC Guy has teardowns of Eco-Worthy dating back a few years, and DC House for about a year, and even says 'Fogstar' has nearly identical build.
 
BarracudaBob said:
Realize you have all of knowledge and experience here to overload your brain. We thrive on complexity.

Here is some very conservatives voltages for you: https://off-grid-garage.com/my-settings/
Click to expand...
There is where I got the numbers I set... what is missing is when is recommended to normally switch back to Utility, at 40?, at 48? or when to switch back to battery? at bulk? at floating? I mean, if the 20-80% rule of thumb used with lithum does not work with LFP for longevity, then what?
 
vallesj said:
There is where I got the numbers I set... what is missing is when is recommended to normally switch back to Utility, at 40?, at 48? or when to switch back to battery? at bulk? at floating? I mean, if the 20-80% rule of thumb used with lithum does not work with LFP for longevity, then what?
Click to expand...
Down the worm hole we go! I had to find what works best for my set of batteries. I monitor everything and been testing these settings. So far I am very happy with them. Will will tell you to go to 57, Andy will tell you to go to 55.2-55.8, manufacture says 58V

You can't go wrong in this area. I am sure others can tweak it a little..

Shutdown battery voltage: 42.2 V (you are dead here)
To grid battery voltage: 46 V (Get off the battery you don't want to go below 20%)
Back to battery voltage: 52.8 V (you are around 50% ish...)
Battery float charge voltage: 54.0 V (53.6 to 54.4)
Battery absorption charge voltage: 56.2 V (good place to watch it balance, Others say 55.2V to 57V)
 
fuzzmunky415 said:
I've been researching them, and info is sparse...Eco-Worthy panels I scored recently (200W bifacial) shipped from SoCal, but say Made in Canada (Canadian Solar?) so there is a link between Canadian Solar and Eco-Worthy. Several YT vids show Eco-Worthy has it's name and website directly on the included literature in the DC House battery's boxes, showing a direct link between Eco-Worthy and DC House. DC Guy has teardowns of Eco-Worthy dating back a few years, and DC House for about a year, and even says 'Fogstar' has nearly identical build.
Click to expand...


Digging even further yields the BMS as being JBD, and Tobi's vid gave up a precious QR Code, which leads to HiThium cells, possibly (more confirmation is always a good thing). I seem to recall reading here or on YT comments, the speculation that they ARE the same company, releasing to different parts of the continent (eg. Eco to Canada, DC House to USA, etc.) but that appears to remain speculation. I wonder if they're simply hedging their bets in a volatile political climate?
 
Guys, I really think it would be advisable to buy and try all the appropriate assumptions. So much the experience is done alone and with the wallet in hand. The only thing is to try to leave as much as possible more informed, the rest is future ...
 
BarracudaBob said:
Down the worm hole we go! I had to find what works best for my set of batteries. I monitor everything and been testing these settings. So far I am very happy with them. Will will tell you to go to 57, Andy will tell you to go to 55.2-55.8, manufacture says 58V

You can't go wrong in this area. I am sure others can tweak it a little..

Shutdown battery voltage: 42.2 V (you are dead here)
To grid battery voltage: 46 V (Get off the battery you don't want to go below 20%)
Back to battery voltage: 52.8 V (you are around 50% ish...)
Battery float charge voltage: 54.0 V (53.6 to 54.4)
Battery absorption charge voltage: 56.2 V (good place to watch it balance, Others say 55.2V to 57V)
Click to expand...
Why return back to battery voltage at about half capacity? why not around 90 or 100%? What is your reasoning for that?
 
You must log in or register to reply here.

Similar threads

L
Flooded battery float and equalization
Replies
5
Views
215
sunshine_eggo
sunshine_eggo
X
Float, Absorption and Equalization V for Lithium Battery ESM-48100B1
Replies
14
Views
390
xuhaibkhan
X
N
How would you set the charging parameters for LiFePO4 DC-DC charger?
Replies
7
Views
464
NBs
N
E
100% SOC, absorption/float for constant loads
Replies
1
Views
295
mikefitz
mikefitz
frankz66
Boost , bulk and float ( 13,80 )
Replies
8
Views
598
pollenface
pollenface

diy solar

diy solar
Back
Top