My build thread with LF280K from 18650batterystore and Sun Fun Kits sfk v4 Heated Kit

[EastFalcon]

Hello,
I would like to share with you my battery build, after seeing videos on Nate's DIY youtube I decided to do the same:

I chose cells from 18650batterystore the LF280K grade A, and the standard heated kit V4 with heating.

The total cost for cells was $644 delivered to Virginia and $373 for the kit. My total spent: $1,017 for all. I think this is going to be a good battery that is heated, has low temperature protection, heating, and Bluetooth connection.

 

[EastFalcon]

One of the cells on has some liquid under the blue cover, I called 18650batterystore and James tells me its nothing to worry about I also read a few people on the forums have this as well and it is ok.

The Sun Fun Kits is most assembled, I chose the option to get my pads soldered for easier connection, I also selected the sidewall as they say it is easier to install this way.

 

[EastFalcon]

So the standard version you can pay to have the wires crimped, but I already have a hydraulic crimper so I will make my own wires, but everything is included actually there is more wire then needed. Its nice silicone 6 awg wire, it is also sfk's own brand.

 

[EastFalcon]

So I started by installing the cells using the 1.00 3d printer walls. They went in fairly easily, its a very nice fit with the foam and the bracket.

 

[EastFalcon]

So this is how far I have gotten to, I install the cells, SFK told me that for the dual terminals you will need 16 m8 bolts and they sent it to me at no charge. They said not use to use the threaded rod included with the package form 18650 as it can not be tighten properly. However, I will show you what I'm stuck on.

 

[EastFalcon]

So here is where I'm stuck at at, they have this part that increases the height but one of its "branches" is hitting the bolt. I sent this to SFK and they said they are shipping a replacement riser to me and it should be arriving today.

So this is where I am at till now, its been pretty good so far except for the cell incompatibility.

 

[Alkaline]

Hi,

Welcome to the forums, nice build thread, let us know how the branch thing turns out.

 

[EastFalcon]

Thanks, I'm checking UPS tracking and it supposed to arrive by 7:00 Pm today

 

[Sam Cho TX]

Hey there,

Nice to see more people building SFK kits, I was going to post my build thread too, but you beat me too it . I went with the v4 standard without heating for 2 of them I also have a v3.5 kit with LF280K non heating as well. Love them.

 

[DIYrich]

M8 bolts? I thought they were M6 holes.

 

[EastFalcon]

I think you are right they are m6 sorry, I not good with metric its about 1/4" thread. But good news I got this new adapter and it fits. Transferred over the electronic board to the new one and now I put on the BMS board. Its pretty nice and thick about 1/8" and is machined fiberglass.

 

[EastFalcon]

Ok so I'll finish up the rest tomorrow, but almost done, I have the wires attached to the top of the case and the heating pad connected to the switch.

Pretty smooth so far. Making the cables and crimping the colored connectors took the longest out of everything.

 

[EastFalcon]

All done! I'm going to charge it and run a capacity test when I get home.

 

[EastFalcon]

Ok I think I have everything set! I'm using this heater and a 1500 watt inverter along with the BMS capacity benchmark. Its running now.
Overall the kit was easy to build I think anyone can do it, the only hard parts are the making the cables and crimps.

 

[EastFalcon]

Test completed last night, I got 278AH.
Is this normal for grade A cells? I was under the impression these usually test much higher because they are grade A.

 

[Sam Cho TX]

Where are your test results post the link.

 

[EastFalcon]

Screenshot? That is what the app said it said 278.38 AH.

 

[Sam Cho TX]

In the app, scroll down you'll see your result, click on the cloud button and it will upload your results then copy the link to the results and post them.

 

[EastFalcon]

I see, very cool thanks Sam!

Sun Fun Kits DIY LifePo4 Lithium Battery Kits & Ready Made AGM / Lead Acid Replacement Batteries for RV, Golf Carts, Solar Storage, Back Up Power, Hurricane Outage . Made in Baton Rouge, LA, USA Ready to Ship out no overseas delay! Sunfunkits.com

Sun Fun Kits DIY LifePo4 Lithium Battery Kits & Ready Made AGM / Lead Acid Replacement Batteries for RV, Golf Carts, Solar Storage, Back Up Power, Hurricane Outage . Made in Baton Rouge, LA, USA Ready to Ship out no overseas delay! Sunfunkits.com

www.sunfunkits.com

 

[Alkaline]

278 AH is very common for LF280K grade A. This is all you can expect. EVE is making a version 3 that is supposed to increase capacity a bit more. I would say your capacity is good.

 

[timselectric]

278ah isn't bad for the first test.
After a few cycles it could improve.
Depending on if the balance improves.

 

[EastFalcon]

On the 18650batterystore website they show these cells are supposed to be 295 or so range:

https://cdn.shopify.com/s/files/1/0481/9678/0183/files/Capture_6e06f765-4b22-4773-b6c1-0b6f1f8655d2.jpg?v=1663390796

But I got only 278.38? Should I run the test again? Or is it bad to full cycle cells.

 

[Alkaline]

This 280K nonsense EVE has done is going to cost them in the long run. You can run the test again you may gain half an AH but you are not going to break 280AH most likely.

Do you have a scanner app what date are your cells?

Nevermind I found from one of your pictures, Date Code CB = 2022, October New cell but behaves same as as last year. My thread:

What is going on here? Just got ZKE-40

Recently, I am thinking relying on AH is not enough to determine cell quality, so I finally ponied up the cash and bought a ZKE-40 tester and tested 1 of my Luyuan 280K cells, matched & batched genuine. As you can see it falls a bit short on the AH, but at the same time exceed the WH of the...

diysolarforum.com

Grade A 280K, 278 is all I got as well, your cell is probably stronger because I was testing directly on the Cell, vs you have a BMS that is probably consuming some AH.

 

[Sam Cho TX]

I also got 278, but with SFK 280K cells: https://www.sunfunkits.com/app/ViewBenchmarkDetails?id=6bc89774f0f4 This is how they test, many people are testing this way.

But the grade B 280K are very low 240-260 range.

 

[timselectric]

I got 287 on mine. (LF280K from 18650batterystore)
Two different batches.
Picking up another 48 cells in a couple of weeks.
I would run the test again. How well were they balanced?