Billwilson
New Member
16 304 ah received ordered 11/01 last week very pricey but perfect so far qr has manufacture date 1 month before order. howard@eelbattery.com
Received first set of cells.
- Thread starter Billwilson
- Start date
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
New Cells need to be Top Balanced/Charged PRIOR to assembly.
Basic Battery assembly guide & related info... I wrote this a couple of years back.
Luyuan Tech Basic Lifepo4 Guide V1.0A
Basic Battery assembly guide & related info... I wrote this a couple of years back.
Luyuan Tech Basic Lifepo4 Guide V1.0A
Billwilson
New Member
I payed a higher price than most, but my request for perfectly matched cells and my meter says they are. Total to my door 1,937.97 us
$121/cell delivered, not bad but now you can order these cells from US based distributors for same cost.
Billwilson
New Member
The cells were suppose to be pre balanced and are resting at 3.3 volts thanks for the pdf my first build.
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
They are NOT and never are shipped fully charged (not allowed). Testing IR (internal resistance) at storage Voltage doesn't count for much. They do have to be Top Charged & Balanced prior to assembly.
Properly Matched & Batched cells are tested through the Working Voltage Range so that the IR is identical when the cells are at 3.0, 3.1, 3.2, 3.3 & 3.4 Volts. Additionally, they would be shipped with a Test Report indicating such. At minimum a Factory Test report indicating the test cycles.
Far too many people have been sold a Bill of Goods with companies who do not properly test, match & batch... Sadly 90%+ of vendors only test IR @ Storage Voltage (nominal being 3.200 Vpc) and call that Matched - IT IS NOT !
Properly Matched & Batched cells are tested through the Working Voltage Range so that the IR is identical when the cells are at 3.0, 3.1, 3.2, 3.3 & 3.4 Volts. Additionally, they would be shipped with a Test Report indicating such. At minimum a Factory Test report indicating the test cycles.
Far too many people have been sold a Bill of Goods with companies who do not properly test, match & batch... Sadly 90%+ of vendors only test IR @ Storage Voltage (nominal being 3.200 Vpc) and call that Matched - IT IS NOT !
Billwilson
New Member
I am currently leaning towards putting them together and see what the heltec active balancer teaches me about them. This will be a emergency setup on a hand truck. I have medical equipment that I need to keep running the massive increase in EVs charging is killing our power grid, plus a massive surge in the wealthy running here from the big cities is to much for a per 1960's power grid.
Billwilson
New Member
Glad I was in no rush to put this pack together, you have me some great links here. I am still looking for a company that sells air gap cell separators since this pack will around long after I am in no need of power and in my will.
Internal resistance via 1000 hertz AC pulse (the only way to test) is the same regardless of state of charge
DC tests will get some other result which can be compared against other DC methods, no idea on their state of charge but I doubt that matters either.
do you know what the mean by “aging testing”?
Yea if you have active balancing it shouldn't matter, even if one's at 10% charge and other cell is at 90% should eventually be balanced, even if it takes a month. I still balance them to have the full capacity "immediately" though
featherlite
Solar Enthusiast
I am grateful that I top balanced my cells before placing in service. For one thing, doing so forced me to focus on the theory behind top balancing, which was a great learning process for me.
Knowing what I now know, I would never skip top balancing.
Knowing what I now know, I would never skip top balancing.
Billwilson
New Member
Impedance matching was a concern for me in my radar days. I will using a sep
https://avt.inl.gov/sites/default/files/pdf/battery/usabc_manual_rev2.pdf. I am just building a hobby pack for a larger UPS and I am sure I will apply many things from youth to this build just to see how my old rotoverter works with this. And the cases of capacitors from my old TV repair shop may now have a chance at being used.
Thank you, ( https://www.large.net/news/6hu43qz.html ) it would be wonderful if this level of knowledge was given to every single car owner.
https://avt.inl.gov/sites/default/files/pdf/battery/usabc_manual_rev2.pdf. I am just building a hobby pack for a larger UPS and I am sure I will apply many things from youth to this build just to see how my old rotoverter works with this. And the cases of capacitors from my old TV repair shop may now have a chance at being used.
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Billwilson
New Member
You just help me decide about the size of battery bank. Ordered another set. I fell like a retired school teacher buying the fastest corvette produced this year knowing I will never need that much power at one time.
- 20 × Battero Tech BT280 3.2V 280Ah LiFePO4 Cells
- Welded Screws: Single M6 Pole
- Busbars and Bolts: Included
- Grade: ESS
- QR Intact: Intact
- Matched IR: Yes
- Matched Voltage: Yes
- US$1,100.00
Sub-Total : US$1,100.00
Seafreight (Cells Only) (Shipping to US): US$307.68
Payment Fee (4.4%): US$61.94
Grand Total : US$1,469.62
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Why the different cells?
