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Luyuan battery case

As we have seen numerous times past....
B/Bulk 280AH cells test out as anywhere from 275-280AH for the GROSS AH meaning from 3.650 down to 2.500 and their usual NET AH were often coming in around 270AH. This improved a little over time but not terribly much.

A-Grade cells usually tested out above the "nameplate rating" but most often only by a few percent, so it was not unusual to see 290AH+/- from the GROSS side and usually hovered around 280AH from the working range.

Now things have yet improved a bit more and now an A-Typical A-Grade (proper) 280AH will test out around 300AH GROSS which will consistently deliver the 280AH from the Working Voltage Range. This applies to the Major Makers across the board.

IF one builds their own Battery Packs or buys commercial assembled units from a company like say SOK and operate the battery packs within the WORKING VOLTAGE RANGE of 3.000-3.400 (2.900-3.475 in practical universe with Low Volt Cutoff no lower than 2.800Vpc) any noticeable deterioration will take YEARS to Notice. A QUALIFIER !!! This also assumes that the battery packs are kept within Nominal Temps (10C-40C / 50F-104F) and NOT ABUSED by being frozen or overheated and such.

Things that can stress cells but in ESS rarely do....
- Pushing the Charge & Discharge C-Rates to the limits.
- Charging & Discharging cells outside of nominal temps.
- Pushing / Using the cells beyond the Practical Working Voltage Range ! (there is no practical gain doing so).
- ESS systems are intended to be Right Sized so as to never stress them while having the real capacities that you really need.

Case in Point using my own system as the example.
Take 6x 280AH Packs in Parallel: Can discharge @ 1,200A collectively and take 600A charge collectively. Obviously I will never pull 1200A / 30,700W from that and while I can "PUSH" 305A Charge (SCC's, Inverter & external charger) I don't do that either (but have tested it in my Thrash Tests which was pushing all gear to performance edge). My SCC's provide 165A which is awfully "gentle" and easy on the packs as it is divided between them.

The BIG Q - Why so big with small solar (2080W & 2370W)... I use between 3.5-4.0 kWh per day (year-round) but in Winter I can easily see 10 days without any significant solar, so my reserve reflects that. Even if I have to use a Genset for 8 hours to charge my bank, 8 hours genset = just under 5 days battery runtime.

These Days (summer 2024) the Availability & Quality of cells has improved for several reasons which is a WIN for everyone ! There is no reason to not buy proper A-Grade Cells now that they are available at reasonable prices (cheaper than last years B Grades) and people CAN SHOP AROUND for the deals too while sticking to KNOWN GOOD VENDORS that have at least 3 years track record.

THE GOTCHA THAT GETS MANY !
Why Match & Batch ! Cells with a Lower IR will take charge & discharge faster that those with a higher IR. They will be runners within a pack and in fact the worst place for them is to be on Position 1, 8/16 (Batt Leads) as that WILL limit & handicap the packs. Matching & Batching ensures that cells collectively have the same IR whether at 3.000 or 3.200 or 3.400 regardless if Charging or Discharging.

SADLY most vendors only IR Match cells at the storage voltage as they received them.
Some Vendors use a 3rd party to Test & Validate cells (They usually charge extra for that)
Some other Vendors use the Manufacturer to complete the cycles (beyond just cell validation tests) & provide the manufacturers test reports.

TOP 10 LFP Makers as of MARCH:2024
BYD
: https://www.byd.com/pc/
Ufine Battery (Guangdong Ufine New Energy Co., Ltd.): https://www.ufinebattery.com/
Contemporary Amperex Technology Co. Limited (CATL): https://www.catl.com/
LG Chem Ltd.: https://www.lgchem.com/main/index
Panasonic Corporation: https://na.panasonic.com/us/
Samsung SDI Co. Ltd.: https://www.samsungsdi.com/
CALB (China Aviation Lithium Battery Co. Ltd.): http://www.calb.cn/
Lishen Battery: https://www.lishen.com.cn/
Farasis Energy (Ganzhou) Co. Ltd.: https://www.farasis.com/
EVE Energy Co. Ltd.: https://www.evebattery.com/

-! Bold/Italics = Most common cells available from Vendors/Resellers selling to DIY & Others.
NON-Bolded = Generally unavailable to "Public" and therefore not easy to get.
 
I'm having some fun building (slowly) my custom metal box but I'm still jelly of that.
 
@ArthurEld you are killing me!
First you let us know that Amy can ship by air, which has taken every bit of (pathetically weak) willpower I have not order something. Now you show that you got your stuff in a week!
Now I know my next glass of scotch is going to cost me several hundred dollars! Somehow I now feel that I need LCDs for my 12V batteries and some "extra" BMSs just in case. Which will then lead me to need some extra cells for those BMSs. Which will then make me need.....
Down the rabbit hole we go!
 
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@Steve_S , l noticed you mentioned using the resistance/voltage tester that Amy sells (YR1035). I have a Klein multimeter (CL800). Will the Klein do everything I need or does the YR1035 do something the Klein doesn't or not as well?
 
@Steve_S , l noticed you mentioned using the resistance/voltage tester that Amy sells (YR1035). I have a Klein multimeter (CL800). Will the Klein do everything I need or does the YR1035 do something the Klein doesn't or not as well?
I had Amy put one in my order that just shipped, I screenshot the description.

DABE90C0-6200-40B5-9990-E47B1F39C1CB.png
A5958362-CEF5-466E-93EA-8C4938D92C89.png
766D0892-E773-41A6-B34B-409AC4C1843A.png
 
@ArthurEld you are killing me!
First you let us know that Amy can ship by air, which has taken every of (pathetically weak) willpower I have not order something. Now you show that you got your stuff in a week!
Now I know my next glass of scotch is going to cost me several hundred dollars! Somehow I now feel that I need LCDs for my 12V batteries and some "extra" BMSs just in case. Which will then lead me to need some extra cells for those BMSs. Which will then make me need.....
Down the rabbit hole we go!
lol, only small items like BMSs come air mail. The biggest item I ordered airmail from China was a MPP Solar inverter. They come through Hong Kong for some reason.
 
There are Two Voltage Ranges and so Two Capacities.
Allowable Voltage Rage = 2.500 to 3.650: This range is where no harm is being done to cells and also if measured, the Gross Capacity rating as well.
The working Voltage Range = 3.000-3.400: This is the Voltage range that delivers the Rated AH Capacity, the NET AH.

If you Capacity test cells from 3.650 down to 2.50 that is the GROSS Capacity of that cell. This should always be reasonably above the NET AH Capacity which is delivered from the Working Voltage Range 3.000-3.400 with NBominal Voltage being 3.200 / 50% SOC.


Yes, a Ferule is required for the wire, most especially the Ultra-Fine Siliconized wire.
View attachment 217912
Thanks Sir
 
My test report did exceed 280ah. All cells were above 313.5ah but I never checked them.
They are the nicest cells I have ever seen and they stay perfectly balanced.
I assume that the capacity of the cells will fall below 280ah. That is what I have read.
Thanks
 
There are Two Voltage Ranges and so Two Capacities.
Allowable Voltage Rage = 2.500 to 3.650: This range is where no harm is being done to cells and also if measured, the Gross Capacity rating as well.
The working Voltage Range = 3.000-3.400: This is the Voltage range that delivers the Rated AH Capacity, the NET AH.

If you Capacity test cells from 3.650 down to 2.50 that is the GROSS Capacity of that cell. This should always be reasonably above the NET AH Capacity which is delivered from the Working Voltage Range 3.000-3.400 with NBominal Voltage being 3.200 / 50% SOC.


Yes, a Ferule is required for the wire, most especially the Ultra-Fine Siliconized wire.
View attachment 217912
Timely response with thanks
 
Well getting closer to getting cabinets made for these battery packs, two weeks of back and forth and I got my first quote.

If I can get a decent price I am going to get three cabinets made two battery and one inverter cabinet to go between. These are IP55 but can have higher weather protection.

I am using the 8s cases but I am having them built for the 16s cases extra depth and weight.

I am also going to get them to design and quote a four battery cabinet as well.

2DCFC2B0-8359-46EC-8934-69ADFC88D2FD.png
 
With that much KWHr what’s your reasoning for sticking with 24v?

IMO it seems if storage exceeds 30-40kwr or peak load >5kw, 48v makes more sense.
 
Well getting closer to getting cabinets made for these battery packs, two weeks of back and forth and I got my first quote.

If I can get a decent price I am going to get three cabinets made two battery and one inverter cabinet to go between. These are IP55 but can have higher weather protection.

I am using the 8s cases but I am having them built for the 16s cases extra depth and weight.

I am also going to get them to design and quote a four battery cabinet as well.

View attachment 218892
How does that EPS sandwich board perform when exposed to flame?
 
With that much KWHr what’s your reasoning for sticking with 24v?

IMO it seems if storage exceeds 30-40kwr or peak load >5kw, 48v makes more sense.
Because this will be movable and a 200lb battery is a lot easier to move than 275lb.
 
How does that EPS sandwich board perform when exposed to flame?
No idea, this is the low cost option, the other is an interior steel panel. I might still go that route. So far they are about $1200.00 before shipping.
 
That’s some storage for a motor home!!
I know. Go big or go home, right!?
A co-worker pointed out that is almost what his Nissan Leaf has.

The reason is that we like disbursed "camping" in the middle of no where. When you are out there, the sound of a generator really kills the vibe.
I want enough power to be able to go at least overnight, including with one of the A/C units.
 
With that much KWHr what’s your reasoning for sticking with 24v?

IMO it seems if storage exceeds 30-40kwr or peak load >5kw, 48v makes more sense.
In my RV there is a lot of existing 12V. It is a lot easier to go from 24V to 12V and vice versa than from 48V to 12V (using Victron DC to DC chargers & converters).

Plus, like @S Davis replied, the weight of a 48V cell becomes an issue. It will be hard enough trying to work a 100+ pound 24V battery into the basement of my RV. I don't even want to attempt that with 200+ pound batteries that are also almost twice as big.

Edit: If I did this size system for my house it would definitely be 48V.
 
I seriously considered moving to 48v with my recent update. Pricing on the Inverter Charger and BMS are essentially the same and battery case prices are close to each other so price wasn't a big consideration.

However if I were to build a 16s 280 AH DIY battery I would likely assemble it in place or get one of the lifts others are talking about. Picking up my 24v case is a chore to put it mildly. On the other hand if I were to use the 100 AH cells which are common in server rack batteries then this not be as big an issue.

Space can also be a consideration. In my configuration it will be easier to place 2 8s batteries on the left and right of my build. For others this might not be a concern.
 
My test report did exceed 280ah. All cells were above 313.5ah but I never checked them.
They are the nicest cells I have ever seen and they stay perfectly balanced.
I assume that the capacity of the cells will fall below 280ah. That is what I have read.
I ordered 280Ah, but the test report claims 313+Ah, that seems weird?
 
Well a little more progress on the custom battery cabinets, starting to get some lower pricing and better design.

B1B2C90A-F445-413E-B767-23E7FA5A04A6.png
 
Order placed on 5/15 for one 24v case and 8 280 cells, added 4 more cells on 5/18.

Just got UPS tracking numbers for 8 packages just went live with no info.

Does that mean they’ve landed state side or they just left China?
 

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