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Sixtysix 280ah Cells from Deligreen

ArthurEld said:
I will check the internal resistance and capacity to see if I get any clues. It will take a long time just to check capacity.
We'll see how far I get with that.
Click to expand...
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How to Measure the Internal Resistance of a Battery?

How to Measure the Internal Resistance of a Battery?: * The schematic is taken from other source. Wondering how well your battery can perform? Don't know how much current you can pull from your battery? Well you can get know to your battery more with a simple experiment. You only need few...
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Steve_S said:
TIP on BusBars...
With that layout you will have busbars of different lengths, generally that is of little issue "provided" you have enough material to compensate for resistance etc...

With the 280AH cells, you will need busbars of 4.250" length for (A) & 3.750" length to go between the cells (B) the 1/2" difference isn't much but it can just a little extra resistance, so you are aware of this. I used C110 Copper 0.250" x 0.750" which 6mm thickness and perfect.
The cell terminals are also only 15mm wide so these will fully contact the terminal face.

Ohh and a friendly reminder: Be certain to clean the cell terminal & bus bars and wipe them down with alcohol, often there is oil/waxes for protection. Ensure that the busbars have no burrs or high spots, chamfering the holes is the best solution


View attachment 25674
Click to expand...
Steve, your replies are always packed with good information.
Sorry for the melting busbar question. For some reason my mind pictures melting busbars and burnt off studs. lol
I bet that would be hard on the aluminum and plastic cells.
Anyway, back to busbar thickness. I looked up the amp rating for copper busbars and .125 thick is good for over 200 amps.
I see a lot of people using braided busbars that look less than .125 thick. I didn't look up how many amps that is good for but it has to be less than 200. I think flattened copper pipe is less than .125 thick also.
My battery set up plan is different than yours. SmoothJoey and I worked it out together. I will have 4 batteries. They will handle 500A charge or discharge. My thinking is that if 2 batteries go down something very wrong has happened but I want to be able to operate with 2 batteries. If 3 go down I don't need to continue. The fuse will blow on the last battery if it gets more than 125A. That last battery will probably be able to continue because my system probably won't even charge or discharge over 125A. But if the fuse blows that is fine because my batteries need attention. If someday I decide to pump more 125 amps through each battery, I will need to make a lot of changes. I don't expect that day to come.
All that being said, I think my system will be fine with .125 thick busbars. Anything thicker would be a lot of unnecessary expense and hassle.
I am still working on busbar thickness in my mind ?. I won't make my final decision until the day I order the material.
 
You know... I'm gonna just be blunt about it. Undersizing is very easy to do. Being "cheap" and bodging thing (squeezing copper pipe, seriously ?) is certainly NOT the way to buy a solid & reliable system. Cheap is NOT Equal to Frugal !
Wanna build a 1000HP Corvette and put Brakes from a 1976 Chevette on it with Bicycle tires ?
Oversizing a little over is generally a good idea because Things Happen, often unexpectedly and then sometimes just evolution because needs / wants change.

I always told people that if you figure everything out and decide that a 4Kw Inverter (excl, surge) would be OK I would suggest get the Next Size up but guess what, I'd get CRapped on for it. Then a year later Mr Smarty is upgrading their Inverter.... I don't tell folks anymore cause I don't need to be crapped on for common sense.

I first built to run with 3KW Inverter with Big Lead Battery Bank, 12 months later I was upgrading to 4KW Inverter... Replaced ALL my 2/0 with 4/0 ($$$ ouch ) new breakers, fuses (more $$$ ouch) then to incorporate Lithium (LFP) another year afterwards... more $$$
BOS = Lots of cash and if you built to one spec at first, the odds are you will be upgrading something later. BTW, just about everyone who goes solar does upgrade some things within 12-36 months to increased need or just under planned at the start.

As the 500A Charge / Discharge.... the 280AH cells are C1 (280A) max output rate (for the commodity cells) and they are recommended to not exceed .5C

I read that long thread between you and Smoothjoey... made my brain hurt.... be careful about getting caught up in minutia.

Please do yourself a favour, remember these are Commodity Cells and not fully matched & batched Premium cells. Ensure your expectations match what you bought.

Just a tidbit of personal info. I was an Core IT System Engineer (Military & Gov) and involved in fault tolerance & failover systems, which encompassed literally every aspect and potential scenarios... Triple Redundancy = Critical life ! Hence where I gained my "hard wired programming" of "Do it right the 1st Time." There is not much room for "just good enough". As I am Offgrid, Rural & Remote and can be subjected to "extreme" weather (1 foot + snowfalls) to twisters in summer ++ I have to depend on my system because I could be property bound for periods... dependability, reliability & safe are essential and approached as such.
 
I was saying that my 4 fuses can handle 500A total. That's 125A each battery.
I expect my setup will charge/discharge each battery at 25A. I might try 50A some day but probably not.
 
I charged one cell with the Riden 12A power supply to 3.61V today. I was afraid to go to 3.65.
The absorb phase took less time than I expected. It settled to 3.59 so far after about 30 minutes.
The Riden worked flawlessly as far as I could tell.
I used 12 awg wire and a 14A fuse. I also used my new coulomb meter without the shunt.
Since the meter is only rated for 10A without the shunt I set the Riden to 9.9A.
The coulomb meter read 3.61 when the Riden stopped charging.
I checked the wires while it was charging and nothing even felt warm.
I'm going to do a capacity test on the cell now to see what I get. Then I'll take it out of the fixture to see if it swelled much.
Will says to charge to 3.625 for individual cell capacity testing. I'll try that if everything seems ok.
 
Good to know. Thanks and will be looking forward to the capacity test and swelling. All of my cells arrived swelled a bit.
 
Gazoo said:
Good to know. Thanks and will be looking forward to the capacity test and swelling. All of my cells arrived swelled a bit.
Click to expand...
That could be one draw-back to having the vendor do capacity testing prior to shipping .... are they going to clamp them while doing that?
 
Bob B said:
That could be one draw-back to having the vendor do capacity testing prior to shipping .... are they going to clamp them while doing that?
Click to expand...
I have no idea. But even if they did isn't it possible the cell would expand after being removed from the clamp? I also wonder what happens when the cells are discharged after expanding. Do they contract?
 
I guess they do contract a little when they are discharged. That might have been the reason mine seemed to swell a little.
When I took the pack apart the cells were charged more. I wonder if it's better to leave them in the fixture when they are fully charged?
 
Well that's the thing. I will not have mine in a fixture when I parallel top balance. So I will see if they expand more. I think, as you discovered they will expand anyways when removed from the fixture.

When I put them is series I will have them in a fixture made of .5 plywood and threaded rods without too much compression and discharge them until the BMS cuts off. I suspect they will still be expanded but might be easier to compress as Steve suggested in the other thread. I think it will be "get the feel of it" type of thing. If anyone has better ideas I am all ears.

By the way, were your cells flat when you received them? I don't recall if you mentioned anything about that.
 
Mine were pretty flat when I received them and they still are pretty flat. I just noticed I could see a little more space near the corners.
I left my threaded rod a little long so I can cut it in half and make two rods for my smaller battery configuration.

edit- I'm charging 1 cell but it's compressed with 15 other cells in one row with no busbars.
 
Last edited:
I purchased a pre-assembled battery pack last year (The ShunBin Disaster). When I pulled the cells out of the casing they were very well bound with fibre strapping (like that used on binding pallets of boxes together). When I cut that strapping to release the cells, the cells expanded a little (fortunately, while being Used Cells they had obviously not been abused. Once I squeezed them gently to re-strap them into their new configuration hey were fine.

The ShunBin Pack sold on Amazon as New 24/400AH actually had 16X Used 175AH Cells... Hence the "ShunBin Disaster".
 
Steve_S said:
I purchased a pre-assembled battery pack last year (The ShunBin Disaster). When I pulled the cells out of the casing they were very well bound with fibre strapping (like that used on binding pallets of boxes together). When I cut that strapping to release the cells, the cells expanded a little (fortunately, while being Used Cells they had obviously not been abused. Once I squeezed them gently to re-strap them into their new configuration hey were fine.

The ShunBin Pack sold on Amazon as New 24/400AH actually had 16X Used 175AH Cells... Hence the "ShunBin Disaster".
Click to expand...
Didn't Amazon help you get your money back?
 
I wrote it all up, it's on here.
Amazon didn't help, shipped direct from vendor. I did eventually get a part refund for the AH discrepency which covered the cost of the first rebuild which included replacing the BMS that came with it, bus bars and wiring. Actually, changing that crappy BMS is what started the whole Chargery BMS thing here as that is when I started the threads after getting my Chargery and then started working with Jason to add Cold Temp support + other updates, including the development of the DCC's and now working with him in regards to the new BMS' with Active Balancing and more... due at end of year or early 2021.

Here is the painfully long thread, if youre totally bored
diysolarforum.com

ShunBin Battery Packs: 12V/24V 100AH and up ! A Complete RIP-OFF ! AVOID

EDIT OCTOBER 2020 ! WARNING !!! ShunBin IS A RIP OFF ! The sell "Advertise 24V/400AH" What they sent was 24V/350AH with USED / ABUSED 175AH cells. I did not update this previously on Page 1, because I thought people would look through the thread. Now I learned some are not. PLEASE...
diysolarforum.com diysolarforum.com
 
I'm doing a capacity test on one cell. It looks like it will take about 10 hours to finish the test on one cell.

This is the tester I am using but they aren't available anymore - https://www.aliexpress.com/item/32822564230.html
They must have updated them. I see some have bluetooth now.
I have another one on the way from China. I have 66 cells to test. It's twice as fast with two testers.

The tester draws 24A. I used 12 awg wire and a 30A fuse. The wires are getting warm.

I noticed the resistance value seems more in line with what others have reported. When I started the test the display showed .12 resistance. When I got to about 75Ah the value changed to .11. I don't even know if that resistance has anything to do with internal resistance. I still don't have the internal resistance tester I ordered.

I will record the info on my spreadsheet to see if I notice anything useful.
 
Gazoo said:
I have no idea. But even if they did isn't it possible the cell would expand after being removed from the clamp? I also wonder what happens when the cells are discharged after expanding. Do they contract?
Click to expand...
The ones I’ve had swell do not shrink. They can generate very high internal pressure from gas. One swelled so much I decided to experiment on it and put a small hole in since it didn’t vent. Based on the smell I think the gas is ethylene and the likely source decomposing ethylene carbonate electrolyte - a one way process. I’m still cycling it in a 1v pack as an experiment, and so far the cell continues to maintain voltage and charge.
 
Dhopewell said:
The ones I’ve had swell do not shrink. They can generate very high internal pressure from gas. One swelled so much I decided to experiment on it and put a small hole in since it didn’t vent. Based on the smell I think the gas is ethylene and the likely source decomposing ethylene carbonate electrolyte - a one way process. I’m still cycling it in a 1v pack as an experiment, and so far the cell continues to maintain voltage and charge.
Click to expand...
That's what I thought. EVE says 2mm expansion is normal. I am pretty sure one of my cell is a little more than that and they were delivered that way. I was able to arrange them so I could make a square pack with 8 cells. The ends where I will mount the plywood are fairly even so I think I will be ok.
 
There was a hurricane getting kind of close to us so I decided to charge up more of my cells.

I bought a 3000W 12V inverter from Harbor Freight. I've got battery backup!

I think my cells could keep us going for a week in the state of charge I got them from China. I need to charge them for top balance anyway.

It's been downgraded to a tropical storm. We're at 65 feet elevation, my house is cinder block and I have hurricane windows and doors.

I can return the inverter. But I will research and buy a different one. It's good to have portable power.
 
We survived the storm without incident. So, I will return the unused inverter.

Since I started charging more cells, I will top balance another 16 and assemble a 48V battery.
Then I'll discharge the battery to check the capacity. Then I'll charge it to see how the cells stay together.
I will use my BMS and battery meter to see what I can find out. I won't use balancing.

I've been using my Mean Well 3.3V 120A power supply for charging cells parallel. There is only one adjustment screw on the Mean Well.
I back the screw out so it won't start charging when I turn on the power. There's no power switch on the Mean Well so I use a power strip.
I connect a clamp meter and voltmeter and adjust the screw until I'm charging at 50A. I watch the volts but I know it is lower than my target.
If I set the volts to my target, it will charge at 120A. I am not in that much of a hurry.
I keep adjusting the voltage to stay between 40A and 50A. But I watch the voltage on the output screws as I am adjusting and when I get to 3.61V I stop adjusting the screw. Since I am in CV mode the amps are dropping as I approach the target. The volts are also rising quickly because there's hardly any amp hours left to use. I keep checking the battery until it reads 3.6V then I turn off the power supply. Since I am so close to 3.61V the power supply is only putting out 2A when I turn it off.
 
Steve_S said:
You know... I'm gonna just be blunt about it. Undersizing is very easy to do. Being "cheap" and bodging thing (squeezing copper pipe, seriously ?) is certainly NOT the way to buy a solid & reliable system. Cheap is NOT Equal to Frugal !
Wanna build a 1000HP Corvette and put Brakes from a 1976 Chevette on it with Bicycle tires ?
Oversizing a little over is generally a good idea because Things Happen, often unexpectedly and then sometimes just evolution because needs / wants change.

I always told people that if you figure everything out and decide that a 4Kw Inverter (excl, surge) would be OK I would suggest get the Next Size up but guess what, I'd get CRapped on for it. Then a year later Mr Smarty is upgrading their Inverter.... I don't tell folks anymore cause I don't need to be crapped on for common sense.

I first built to run with 3KW Inverter with Big Lead Battery Bank, 12 months later I was upgrading to 4KW Inverter... Replaced ALL my 2/0 with 4/0 ($$$ ouch ) new breakers, fuses (more $$$ ouch) then to incorporate Lithium (LFP) another year afterwards... more $$$
BOS = Lots of cash and if you built to one spec at first, the odds are you will be upgrading something later. BTW, just about everyone who goes solar does upgrade some things within 12-36 months to increased need or just under planned at the start.

As the 500A Charge / Discharge.... the 280AH cells are C1 (280A) max output rate (for the commodity cells) and they are recommended to not exceed .5C

I read that long thread between you and Smoothjoey... made my brain hurt.... be careful about getting caught up in minutia.

Please do yourself a favour, remember these are Commodity Cells and not fully matched & batched Premium cells. Ensure your expectations match what you bought.

Just a tidbit of personal info. I was an Core IT System Engineer (Military & Gov) and involved in fault tolerance & failover systems, which encompassed literally every aspect and potential scenarios... Triple Redundancy = Critical life ! Hence where I gained my "hard wired programming" of "Do it right the 1st Time." There is not much room for "just good enough". As I am Offgrid, Rural & Remote and can be subjected to "extreme" weather (1 foot + snowfalls) to twisters in summer ++ I have to depend on my system because I could be property bound for periods... dependability, reliability & safe are essential and approached as such.
Click to expand...
yes, I am working toward the redundant system. I had a power outage 1x for 3 days and used a kerosene heater to keep from freezing. the kerosene heater backfired in the middle of the night when we were all under blankets trying to stay somewhat warm. it blacked everything in the house with soot and essentially all of the clothes were ruined even by going to the dry clearers with the specialty cleanup crew. $10000 dollars damage. had insurance but I prefer to not be without power and learn from my dumb mistakes of 30 years past.:rolleyes:
 
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