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  1. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    If the voltage doesn't drop below your float voltage then there is a small current going to your cells. Whatever you are using to measure the current might not be able to measure that small a current.
  2. Gazoo

    How to tell the difference between Grade A and Grade B cells.

    I am a little late here but just curious. Out of the 530 orders how many were for batteries....if you don't mind my asking.
  3. Gazoo

    How to tell the difference between Grade A and Grade B cells.

    I have had a few good experiences with Aliexpress and zero bad experiences. But none of the items I ordered were batteries and I would never order batteries from them. So many on this forum have posted bad experiences ranging from bloated cells to capacity less than advertised to fake QR codes...
  4. Gazoo

    Can LiFePO4 Batteries Combust in Thermal Runaway Event?

    I don't think it is. We have been through this many times before and I believe it's leakage current at least with the EVE cells. But I also think there are certain scenarios that could cause problems and it's good to put insulation between the cells especially in a mobile environment. In the...
  5. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    Sad this thread turned into something complicated when actually maintaining LFE is so simple. Anyways I had to tear down my pack because I moved and haven't set it back up yet. Before I moved I tested the capacity of my pack which had been floating at 3.4 volts per cell for 8 months. I use the...
  6. Gazoo

    EVE-280 cells should these be clamped tight or spaced for expansion?

    I know there was a photo posted somewhere of the hydraulic fixture they use for testing. It does apply the same force no matter the SOC. and this came from another source. I don't know what they mean by fixture. I think the best information we have from EVE came from the conversation...
  7. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    Curious if you have you studied any of the manufacturers spec sheets? Typically, cells are rated for at least 2000 cycles at full C rates. EVE makes high cycle claims depending on C rates. If I only got 1000 cycles out of a LFE cell I would be severely disappointed. Granted the cells don't...
  8. Gazoo

    EVE-280 cells should these be clamped tight or spaced for expansion?

    That may be true of some Chinese companies. But I am quite certain battery manufacturers like EVE, CATL, Lishen and the other big ones including Samsung and LG stick by whatever they document in their spec sheets. There have been people post on this forum who have good functioning cells after 10...
  9. Gazoo

    EVE-280 cells should these be clamped tight or spaced for expansion?

    As far as I can recall that document was supplied to Amy Wan by another forum member as a favor to her. It's a basic guide and compression is tricky unless using springs. It's good to keep in mind too much compression is worse than no compression. EVE has made recommendations for compression...
  10. Gazoo

    Pack / Cell compression Optimized By Using Springs.

    I have the older 280ah cells and they are kinda like what was explained here. I did slight compression with a full SOC. I have not tried to flatten them out and I have not installed my braided busbars yet. Having said that I have noticed the cells expand while charging and contract when...
  11. Gazoo

    Pack / Cell compression Optimized By Using Springs.

    That's very true and another reason it's recommended to put a spacer between the cells even if using springs. If using in a stationary environment like I do one doesn't need to be too picky although since watching my cells expand and contract, I have always recommended using braided bus bars no...
  12. Gazoo

    Pack / Cell compression Optimized By Using Springs.

    The compression PSI recommended by EVE is to be maintained across all states of charge. That's the reason springs seem to be the best choice, but I think foam would be a good second choice. EVE uses a hydraulic jig to compress the cell when they do their analysis to ensure perfect compression...
  13. Gazoo

    NEW Bluetti Sodium Ion Battery Power Units

    I posted an update in the thread I started here concerning Sodium Ion cells.
  14. Gazoo

    CATL Sodium Ion Cells

    I sort of lost track of the progress of Sodium Ion cells. I looked into it some more today due to the discussion in the Bluetti thread. I was surprised to find CATL has been manufacturing these cells since July of 2021 just like they said they would. And we can expect to see major improvements...
  15. Gazoo

    Our NEW GO-TO LiFePO4 vendor...09.20.21

    Hi, I don't have a photo but what I did was mount it to the threaded rods on the sides using zip ties. I used a bottle cap for a spacer to keep the BMS separated from the cells.
  16. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    Sorry. I meant to add that and forgot :oops: 70 to 73 F since I received the cells on 10/16/2020.
  17. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    Test completed. DISCHARGING: Discharge C rate is very low....apx .06C. DROK meter displayed 265ah's with full battery and 11.5ah's with an empty battery. I don't fully trust it because it uses a Hall Effect sensor. BMS displayed zero amps remaining and still discharging because it's not...
  18. Gazoo

    Our NEW GO-TO LiFePO4 vendor...09.20.21

    I have a photo but I haven't finished it yet. I used 1/4 plywood and threaded rods. I probably should have used 1/2 " plywood but it works. Many have used this method. HRTKD posted a link to one of the many threads on this topic. Although that thread is quite extensive and long it's interesting.
  19. Gazoo

    Best LifePo4 charge controller settings known to man for Maximum Service life and Minimum battery stress!!! 5,000-10,000+ cycles?

    I am using my 8 EVE 280ah cells with a UPS and according to my notes have not cycled them since June 25th. of last year. I have balanced them using the BMS several times because I have one cell that tends to drift down very slowly. We have had a few power outages that did not last long and as...
  20. Gazoo

    Top Balancing "How to"

    No. Those are Litokala QR codes you see in the image and they do not manufacture cells. It looks like they have covered other labels with their own labels. Also all of the cells I have seen have the QR code etched into the aluminum on top of the cell and it is visible. If you don't end up...
  21. Gazoo

    Top Balancing "How to"

    If the cells are capacity matched, they should be within a few amps of each other and the BMS can be used to balance them. It shouldn't take long even with a low amperage balancing current. By keeping an eye on the BMS you will be able to see if anything is out of wack. Personally I would not...
  22. Gazoo

    Our NEW GO-TO LiFePO4 vendor...09.20.21

    It's nice to know under ideal conditions cells will last a long time :p
  23. Gazoo

    Our NEW GO-TO LiFePO4 vendor...09.20.21

    There are several references to CATL's 12000 cycle life cells if one does a google :) I would really love to see a spec sheet for these cells as well as the price. As far as I can tell CATL made the announcement in 2019. It might be Evlithium can get them. I personally have no interest in...
  24. Gazoo

    NEW Bluetti Sodium Ion Battery Power Units

    I started a thread about Sodium Ion cells and CATL is the inventor/manufacturer. Glad to see something coming of this and hopefully we can learn more.
  25. Gazoo

    Laser welded studs of screw in?

    If the studs are properly welded it should not be a problem other than the surface area if loads exceed 150 amps. It was determined 4nm of torque (35 inch pounds) is equivalent to 700 pounds of axial force. Provided the contact area is clean that should be enough torque and was the maximum...
  26. Gazoo

    Laser welded studs of screw in?

    I have attached a photo. The stud is stainless steel and the mount is aluminum. So aluminum is welded to aluminum.
  27. Gazoo

    Compression question for EVE LF280K

    Swelling is normal and even with low C rates it's going to happen. My biggest concern is terminal stress due to lack of any compression. I think the best way around this is to use braided bus bars. Personally I am not concerned with compressing to extend cycle life. My cells are stationary...
  28. Gazoo

    Laser welded studs of screw in?

    If drawing around 150 amps or less I would go with laser welded studs. This was tested by someone with good results. Screw in is very easy to strip but there are ways to minimize the risk. If drawing more than 150 amps then I would probably go with screw in studs because the terminal surface...
  29. Gazoo

    Top balancing, a more practical method?

    I believe cells could have the same IR and voltage and still not be capacity matched. I have learned a lot about having non capacity matched cells and if I ever buy cells again I will make sure they are capacity matched. If the cells come capacity matched meaning the capacity of the cells are...
  30. Gazoo

    CATL 271Ah cell issues.

    I am very surprised Michael wants the damaged cells back. He should arrange for transporting the cells to him at his expense especially if they are a hazmat issue (leaking). On the upside at least you don't have to worry about disposing them.
  31. Gazoo

    CATL 271Ah cell issues.

    Thanks to both of you for confirming. As much as I don't like this mess I also think it's a good idea to nip rumors in the bud....so to speak. I had previously posted I could not understand why Michael would want the cells returned to him. And as I recall, people who filed PayPal disputes...
  32. Gazoo

    CATL 271Ah cell issues.

    In all fairness I believe PayPal is asking for the return of the cells and not Michael and it's an auto generated response. Did you or anyone else clear this up with PayPal?
  33. Gazoo

    Beware @Michael B Caro

    I also had a very positive experience with Michael. I am not defending him and there is plenty I don't like about what's happened including some of Michael's words posted on this forum. However, I do not believe he intended to rip anyone off. And I do believe he is sick about what happened. I...
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