Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Neeeeeeey

Options
«1

Comments

  • Registered Users Posts: 433 ✭✭jasgrif11


    What are your settings for the following?

    Cell(S) 16

    StartVol(V) ?

    MaxBalCur(A) 4.000

    SleepVol(V) ?

    EqualizationVol(V) ?

    BatCap(Ah) ?

    BatType ?

    Buzzermode ?



  • Registered Users Posts: 3,384 ✭✭✭randombar


    I'm using defaults so hopefully someone else can fill that in.



  • Registered Users Posts: 3,197 ✭✭✭irishchris


    Cell(S) 16

    StartVol(V) 0.005

    MaxBalCur(A) 4.000

    SleepVol(V) 3.4

    EqualizationVol(V) 3.475

    BatCap(Ah) 200

    BatType LFP

    Buzzermode Shut


    Using the above myself



  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    When I got my battery balanced, I start balancing at 3.51 and sleep at 3.5.

    And turned off all balancing on the bms.



  • Registered Users Posts: 3,197 ✭✭✭irishchris


    Cheers, might up mine to similar so.

    Different question here though, Have mine set to max voltage of 3.65 per cell in BMS. Just wondering what is the max others here let their battery charge to?



  • Advertisement
  • Registered Users Posts: 3,384 ✭✭✭randombar


    Good call on turning off the Seplos balancing!



  • Registered Users Posts: 433 ✭✭jasgrif11




  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    There is barely 1% SOC difference between 3.4V and 3.65V and only another fraction of one percent between 3.65V and 4.2V (the max of LiFePO4)

    When I have a very out of balance pack and want to top balance it as aggressively as possibly, I set the max in the BMS to 4V temporarily



  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    @graememk - good call on the switching off passive balancing in your BMS (like Seplos) as it just wastes electricity by burning top cells. The complete opposite of active balancing where higher cells are drained into capacitors and the capacitors are then used to charge the lower cells



  • Registered Users Posts: 433 ✭✭jasgrif11


    All,

    Does this look correct? The Neey has been plugged in for 5 days. The screen captures are from this morning when the battery is at 20% and on standby




  • Advertisement
  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    Looks fine to me,

    The neey only top balances so looking to see balance at 20% isn't that relevent. It's when cells are at 99% full is when it's important.

    It won't balance until a cell gets above 3.475.

    There is a low cell there vs all the rest but until you see the top end charge voltages you'll not know if that is the "weakest" cell or just imbalance.



  • Registered Users Posts: 3,197 ✭✭✭irishchris


    Mine seems to have kicked on after being plugged in for last few weeks. Sits at 2-3mv when at 100%. Even at high end of charge of 3.6v there is only about 10-15mv difference before settling.

    The cells were well balance but still used to have about 80-100mv difference in them when settled before the neey



  • Registered Users Posts: 433 ✭✭jasgrif11


    Here are the readings a few hours later when the battery is at 99.9%. Should I lower the sleepvol?




  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    You need to see the voltages when it is still being charged.

    You can only really determine if a battery is fully charged is when all cells are at least above 3.4, although I'd prefer 3.5



  • Registered Users Posts: 433 ✭✭jasgrif11


    ok so I'll check when the battery is in charging mode and report back. Thanks



  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    No, just check when the battery is fully charged and taking no more charge. Then post up the cell voltages here



  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    Yes but if the bms thinks the battery is full, it will tell the inverter to stop charging.. even though it might not actually be full.



  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    Indeed. But it would be a good indication of how balanced the cells are when the first cell hits the maximum. Obviously if the BMS had already decided the battery was full because of some ill-judged SOC calculation, there's nothing much we can do about that 😁 Except of course to tell it to mind its own business and just do its job (protect the battery / cells) rather than attempt to do things above its paygrade 😂



  • Registered Users Posts: 433 ✭✭jasgrif11


    So the battery is fully charged according to the BMS (interesting that it's 99% and not 100%). Should the cell voltages be higher or is this their natural resting state?

    Essentially I'm looking to know if this all looks normal :)




  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    No, it's not fully charged. BMS got it wrong. They get it wrong most of the time. 3.34V is about 85-90% charged. It's pretty well balanced though so I wouldn't worry about it. Except for the BMS stopping you using your full battery.



  • Advertisement
  • Registered Users Posts: 433 ✭✭jasgrif11


    The rated Capacity in the BMS is 190.00Ah, should I manually set this to 200.00Ah in the BMS

    What is the best way to get the extra 10/15%?



  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    I don't know how you can do it in the seplos, but can you make the SoC lower, allowing the battery charge more.



  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    Heres yesterdays full charge, Sits at 3.3x v for a long time and the last few % the voltage rapidly rises to 3.6 in the last % or 2.

    The only time you can tell a state of charge from LFP batteries is when they are at 3.5-3.6 then they are more or less at 100%

    BMS's once they have a reliable 100% can then count the power in and out of the battery to guess the SOC.

    Other things that can influence the charge voltage (and discharge) is how much power you are pulling from the batteries. So a true 100% is 3.6V and a low charge rate.

    when mine hits 100% you can see the inverter stopping and the voltage immediately dropping off.



  • Registered Users Posts: 65,272 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    @graememk - not so much the 3.3x V you mention but from your graph it looks more like very high 3.3x V (which by all means is 99% charged). A low 3.3x is only 70% or so.



  • Registered Users Posts: 3,384 ✭✭✭randombar


    Just to help those putting it in, listing the colour cable config with the seplos + Neey


    Seplos - Neey

    Black - Black

    White - White

    Yellow - Blue

    Orange - Green

    Red - Yellow

    White - White

    Yellow - Blue

    Orange - Green

    Red - Yellow

    Black -

    White - White

    Yellow - Blue

    Orange - Green

    Red - Yellow

    White - White

    Yellow - Blue

    Orange - Green

    Red - Yellow + Red



  • Registered Users Posts: 3,384 ✭✭✭randombar


    Hey Graeme, just wondering if you had any clips to mount the neey nicely? What do people use?



  • Moderators, Home & Garden Moderators Posts: 6,012 Mod ✭✭✭✭graememk


    I don't.. double side tape?

    Could draw one up from a rough sketch.



  • Registered Users Posts: 3,384 ✭✭✭randombar




  • Registered Users Posts: 5,115 ✭✭✭John mac


    Andy on off grid garage used velcro strips . looks sturdy enough



  • Advertisement
  • Registered Users Posts: 3,384 ✭✭✭randombar


    Balancing nicely now. Happy days.

    https://capture.dropbox.com/JtSdUKKVDLtguA6w



Advertisement