Lishen 272AH thread?

[michael d]

Okay - thanks. That's not a lot of threads to work with... I will plan accordingly. Also provides further confirmation that using studs (grub screw backed off 1/2 turn) instead of bolts may give me the best chance to use all available threads rather than trying to find the perfect length bolt/washer/terminal stack height.

-uberpixel

the studs work better in my opinion. the studs allow you to safely place the busbars or cables on when assembling the battery, then put on the flare nuts. you will want 20mm long studs (grub screws). I have assembled 4 16cell 24-volt batteries. I tried the bolts but removed all of them and replaced them with studs on the second batch of 32 cells. ?

 

[hilndr44]

fwiw, regarding the fire, I had a solar charger detonate on me 2 years ago. My PV voltage was under the limit (even with temp coeff included), but I heard a large pop while working in the garage, and flames started coming out of the unit. Inside the unit, it looked like one of the wires might have had a defect in the insulation, and it was enough to cause a fire. The company gave me excellent support though, and shipped me a new controller within 2 days. I was lucky, and there was no further damage.

 

[stobbie]

In the back you see the four cells that have survived the fire. I've done a few capacity tests, and they are around 270Ah, so it seems the fire did not damage them. Vents have melted, and black top is also a bit melted. Now I have connected a few new 272 Lishen with a BMS. I haven't top balanced them, I have only paralleled them for two weeks. They did 275Ah in the first capacity test. They are within one millivolt of each other, should I still top balance them? At this moment I am doing a capacity test on my four year old 200ah Winstons, to see how much is left in those..
This new 30 amps Victron charger is running quite hot at 55 degrees celcius .... The Chinese coulomb counter seems quite accurate..

 

[Luthj]

In the middle range 1mv could be 5-8% SOC difference, so I suggest top balancing.

 

[stobbie]

It is at the top, but I will do a top balance to be sure. The WInstons did very very well.. 227Ah from 3.4 tot 3.1volts from 200Ah cells

 

[stobbie]

Almost ready again, 3d printed brackets for compression and an enclosure for the BMS.

 

[Luthj]

Do you think heat dissipation will be an issue in that BMS enclosure?

 

[Just John]

Almost ready again, 3d printed brackets for compression and an enclosure for the BMS.View attachment 37637

I suggest something like Anderson connectors to plug in a charger this time. Much better than alligator clips.

 

[wholybee]

Late to the thread. Re: the fire. Likely impossible at this point to know the cause. However, if you have a 2p4s configuration, and one cell fails and shorts internally, the cell paralleled to it is now directly short circuited. Like putting a wrench across the terminals. I imagine that would cause a fire like you experienced.

Anyway, for the most robust install, if you do a 2p4s bank, you should fuse between the paralleled cells. Then, if a cell fails, the fuse will blow, and leave you with a still functioning and not on fire bank, just at reduced capacity. A 2p4s bank would require 4 fuses.

 

[stobbie]

Do you think heat dissipation will be an issue in that BMS enclosure?

At the back the enclosure is open, and at the front there is the grille. But I will have to monitor it for a while. But with max Amps of 50 my BMS has never even got warm while carging or discharging. So I think it will be OK.

 

[DJSmiley]

Late to the thread. Re: the fire. Likely impossible at this point to know the cause. However, if you have a 2p4s configuration, and one cell fails and shorts internally, the cell paralleled to it is now directly short circuited. Like putting a wrench across the terminals. I imagine that would cause a fire like you experienced.

Anyway, for the most robust install, if you do a 2p4s bank, you should fuse between the paralleled cells. Then, if a cell fails, the fuse will blow, and leave you with a still functioning and not on fire bank, just at reduced capacity. A 2p4s bank would require 4 fuses.

If you would do it that way, i'd suggest 8 fuses.

2 fuses in series between the cells, and add the wire to serie-connect them between the both fuses so it would be

cell - fuse - wire to next pack - fuse - second cell.

Any fuse will cause a voltage drop. If you only use 1 fuse for each 2p, 1 cell will have a lower voltage and they won't have an identical SOC. Although this is minimal, its still there.

but actually, I never have seen anyone complaining about a cell failing and internally shorting. All fire-related issues I've seen with LFP are always NOT the cells, but caused by external causes.

 

[wholybee]

cell - fuse - wire to next pack - fuse - second cell.

All that would do is double the voltage drop. Probably better to add the second fuse on the negative link between cells.

You would also want to arrange the links such that for a pair of paralleled cells, the positive link to the next pair came off of one cell, and the negative link to the previous cell came off the other. That is a mouthful, I hope you can visualize it. It actually happens naturally in most configurations so probably don't need to worry about it.

Cell failure is probably rare outside of physical damage, but that doesn't mean you shouldn't design a system able to deal with it. I personally think that cell failure is a more likely cause of this fire than anything else, even if it was a failed charger/BMS that damaged the cell to start with. I don't think anything other than a direct short of a cell would have caused the heat required to burn up the bank. A charger probably could not have created enough current for that, the charger would fail and stop working far before a fire. And that the fire self-extinguished supports that. It only burned while high current flowed. Once the cell burned open and current stopped, the fire went out- IE no thermal runaway.

This is of importance to me, as I am designing a system for my boat. If that fire had happened 1000 miles from land, I would be dead. $100 in fuses is cheap insurance.

 

[shorawitz]

Whoohooo! FedEx just alerted me my shipment was tendered to FedEx. Bar any acts of God, I should have batteries on Tue 02/23/21. 64 pieces (I'm kicking myself I didn't order extras.)

 

[Tuscumbia]

Hello Everybody,
I ordered 16 Lishen 272 cells at Basen at the end of December 2020. They arrived on February, 18th. Here is what a figured out in the last two days:

1. They were packed in 4 boxes a 4 cells verry well with big foma all around. I guess you can drop the box from at least 3 feed and nothing will happen. Good!

2. They came with busbars, studs and nuts. Good!

3. In one box was a note that they had to wrap them at Basen with theyr own staff. They came from the factory without PVC shrink because they were in a hurry? That sounds strange and I cant believe it. Not good!

4. 15 cells look the same with a clear valve window, one looks different with a blueish window. I guess they mixed cells from different manufacturers or production lines. Not good!

5. One cell has the terminal rethread. It was drilled out of the center. Not good!

6. I did a capacity test with the first cell (with the faulty thread). First I charged it up (single cell) to 3.65 volts and a cut off current of 1 Amp. Than I let it sit for 1 hour and did a voltage drop test (3.553 volts) and tested the inner resistance (0.14 mOhm). Both values are within the specs from the datasheed (voltage drop one hour after charge >= 3.35 volts) inner resistance 0.12 mOhm +/- 0.05 mOhm). Than I discharged it with 20 Amps to 2.5 volts. That took 14 hours and 37 minutes. Capacity was 292.30 Ah. Good!

After discharging I charge up every cell with 100 Ah and stop charging. (The manufacturer recoments storage SOC within 20 - 40 %).

It will take a longer time to test every single cell by itself but I take my time and let you know.

My tester is logging the whole discharge process in a .csv file. If somebody is interested in, I can provide that file.

Gruss aus Deutschland, Michael

 

[Tuscumbia]

Update: The second cell from Basen (with the blueish cap) has 290.8 Ah with IR 0,14 mOhm also. So the first two I tested are much higher than the ratet 272 Ah but I will test all 16 in the next 2-3 weeks. I also ordered a bigger battery tester that can charge and discharge 40 Amps. The one I use at the moment is verry good and I like it but it only can charge with 5A and discharge with 20 Amps. Till the new one arrives I charge the cells with my Riden 6018 that can charge up to 18 Amps. I keep you up to date.

For now I can`t see any difference in the Lishen cells with clear or blue valve window. IR and capacity are about the same.

Michael

 

[Tuscumbia]

Hello again, I did the 3rd cell and also scanned all the QR-Codes from all the cells to find any differences. Here ist the list with the QR-codes:

cell # QR code # remarks capacity
________________________________________________________________________________
1 08BCBPB 11 9 C 01 19 C4 A 120980
2 08BCBPB 11 9 A 03 19 AM A 120345
3 08BCBPB 11 9 A 03 19 AG A 221355
4 08BCBPB 11 9 A 03 19 AM A 120682
5 08BCBPB 11 9 A 03 19 AK A 123011
6 08BCBPB 22 9 6 05 19 7G A 210052
7 08BCBPB 11 9 A 03 19 AG A 221409
8 08BCBPB 11 9 A 03 19 AG A 220870
9 08BCBPB 11 9 A 03 19 AM A 120555
10 08BCBPB 22 9 6 05 19 7G A 210018
11 08BCBPB 11 9 A 03 19 AG A 220456
12 08BCBPB 11 9 A 05 19 AM A 221006
13 08BCBPB 11 9 A 03 19 AK A 121208
14 08BCBPB 11 9 A 05 19 AM A 220641 293,0 Ah
15 08BCBPB 11 9 A 03 19 AG A 220471 with a bad terminal 292,3 Ah
16 08BCBPB 11 9 C 07 19 C0 A 121171 with blueish cap 290,8 Ah

What is the QR code saying?

08BCBPB 11 9 C 07 19 C0 A 121171
[Lishen 272 prismatic cell?] [?] [?] [?] [month?] [year?] [??] [?] [serial#?]

That just came from my mind, I really don´t know. Has anybody information?

The thing with the month and the year is because numbers 1 - 15 have the clear cap and are all within 01-05 (january - may). The one with the blueish cap has a 7 (for july). Maybe they had delivered blueish caps around june. And all are produced in 2019 and old stock / that´s why they are so cheap?

Capacity is very high and close together till now (tested 3 of 16).

If anybody has information about decoding the QR-code please let us know. I have realy no idea and the above is just one posibility.

Michael

 

[Just John]

Lishen has published nothing that we know of about how to decode the QR data. If you find anything published, please let us know. In the meantime, your theory or guess is as good as any other.

In the meantime, all 3 of the 272AH cells you have tested have more capacity than any of my Eve 280AH cells.

 

[shorawitz]

Just received my cells today. Opened up all of the boxes and did an initial voltage test. Labels are all the same: 272Ah, Voltage: 3.29 (all cells tested ~3.297 +/- .002,) and IR: 0.12 mOhm. I don't have a tester that discharges individual cells - only charges up to 30V/10A. I'll have to build a 24v pack to test as my smallest inverter is a 24V 1200W.

I did receive 5 of the blue ringed caps like Tuscumbia reported. I'll report back when I have something interesting (maybe I won't have to post as everything will be normal.)

 

[Bud Martin]

Just received my cells today. Opened up all of the boxed and did an initial voltage test. Labels are all the same: 272Ah, Voltage: 3.29 (all cells tested ~3.297 +/- .002,) and IR: 0.12 mOhm. I don't have a tester that discharges individual cells - only charges up to 30V/10A. I'll have to build a 24v pack to test as my smallest inverter is a 24V 1200W.

I did receive 5 of the blue ringed caps like Tuscumbia reported. I'll report back when I have something interesting (maybe I won't have to post as everything will be normal.)

I also received LISHEN replacement battery with blue ring vent, the capacity test also came out good.

SHENZEN BASEN 280Ah, I received my first order

You go in your order detail and there is a refund button. My post seems weird here, I add it cause out of 17 cells i received 16 of a kind and one different. Just to add to the idea that they send what they got, it's not very... professional. (My feeling). Thanks. I am curious, did they ship...

diysolarforum.com

 

[Tuscumbia]

Can anybody check with theyr cells if the datecode makes sense?