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    BMS showing different Voltage than Shunt

    Here is the amazon link to my charger. I did notice that the amount of amps it outputs decreases by quite a bit when the battery is nearing full so I don't know if that means the charger is able to regulate its charging voltage to something else than 14.6V all the time. As for the smart shunt...
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    BMS showing different Voltage than Shunt

    My charger is set to 14.6v by default and can't be adjusted. Could I just keep an eye on it and unplug the charger when I see a 14.0 reading from the BMS?
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    BMS showing different Voltage than Shunt

    So do I stop charging when the battery reaches a non-nominal 14V or is 14V the nominal voltage that it's supposed to settle to sometime after being fully charged?
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    BMS showing different Voltage than Shunt

    I think you're right! I turned the charging button back to on and now the voltages are consistent! I just thought I should keep the charging button to off when I'm not charging. Have I done any damage by using the battery with the charge button on off? I can hear a humming noise perhaps coil...
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    BMS showing different Voltage than Shunt

    Here are couple pictures I managed to take, but I don't think you can tell anything from the clutter. I did loosen the nuts on the bus bars in these pics so that's not what it's like when fully connected. I'll report back with voltage measurements when I get some time this week.
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    BMS showing different Voltage than Shunt

    The charge button was automatically switched to off after the battery voltage hit 14.6v during charging. The screenshot was taken shortly after a full charge. The highest temperature I've seen was 32c which is well below the over temperature release and it never been below freezing.
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    BMS showing different Voltage than Shunt

    Sorry I forgot to point out that the fuse is before the main switch so it's the closest component to the battery positive.
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    BMS showing different Voltage than Shunt

    Room temp is about the same. This is a plastic ammo box. Could it heat up even when there's no load because of this voltage difference?
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    BMS showing different Voltage than Shunt

    I will do that when I get some time this week. The max load I use is 80W which I think should be ok for the time being. So the extra resistance could be from loose wiring?
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    BMS showing different Voltage than Shunt

    This is a portable system I put together in an ammo box so I basically will need to disconnect a lot of the wirings in order to take a picture and it will be hard to get the details in the picture because there are a lot of wires in a very compact space. Are you trying to spot a loose...
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    BMS showing different Voltage than Shunt

    Here is my post of the wiring diagram. The only difference is that instead of the 3x 8AWG wires connecting the BMS, it's 2x 6AWG wires. The shunt has a positive lead connected to the positive terminal of the battery.
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    BMS showing different Voltage than Shunt

    My BMS is showing a different voltage than my victron smart shunt. What could be the cause?
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    Does a LiFePo4's charge rating lower as capacity degrades over time?

    I see that most LiFepo4 cells have a charge rating of 0.5C which means for a 100ah cell, you can charge it at a max of 100ah * 0.5C = 50 amps. Since after a certain amount of cycles, the battery cells will degrade to only 80% of its original capacity, does the max allowable charging amps(50a in...
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    Are there any downsides to charging LiFePo4 fast?

    It's not a SCC, but an A/C adapter that plugs into a normal wall outlet(link). I plan to charge it about 2 times a week. Though my cells are not grade A cells and are probably at 80% the original capacity; would this lower the 0.5C charge rating?
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    Are there any downsides to charging LiFePo4 fast?

    I have a 12V 100ah LifePo4 battery connected in 4s. On Amazon, I see a 14.6V 40A charger and a 20A version. I'm tempted to get the 40A charger, but am not sure if charging that fast will degrade the battery more and cause any heat issues. I'm using 2 AWG wires with a 120A fuse so I'm not too...
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    Is it a good idea to have a disconnect/kill switch for a 12v system?

    That's a very good point. Though it is a 12v battery/system so wouldn't that be pretty safe to handle even without any sort of disconnect since the voltage is low to begin with?
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    Is it a good idea to have a disconnect/kill switch for a 12v system?

    I'm using a BMS with a battery in a 12v 4s configuration and the BMS has a bluetooth function that lets me toggle battery discharge on or off from my phone. I was wondering if it is still a good idea to have a physical disconnect/kill switch or would it be pointless?
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    Is there anything wrong with my wiring diagram?

    Thanks for the input. I guess I'll size up the 100A fuse. I only plan to use one outlet at a time so I think I can get away with a 120A fuse instead.
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    Does power supply output current drop as LiFePo4 cell becomes more charged?

    So when the battery cell is at full capacity, does the output current reading from the converter drop to 0A? Also if I leave it connected to the battery cell after reaching full capacity, is there any danger of over charging?
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    Is there anything wrong with my wiring diagram?

    I'm building a portable LiFePo4 power bank for the firs time and was wondering if anyone could give an opinion/advise and possibly point out flaws if there are any. I plan to charge it through the PowerPole connection.
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    Does power supply output current drop as LiFePo4 cell becomes more charged?

    I'm charging up a 3.2V LiFePo4 cell with an adjustable converter. I have the voltage set to 3.65V and when I initially started charging, the output current was at 11Wh, but as it charges over time, the power output of the converter steadily becomes lower. Right now it's charging the cell at...
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    Thanks for your help, I learned quite a bit. I will just return the 0.9V one.
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    Is full resting voltage at 3.4 volts ok? I'm just wondering if it's worth trying to return given the $100 per cell price. At the moment, I plan to return the 0.9V cell.
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    Here's the listing(https://www.ebay.com/itm/115016791435). I guess it doesn't say "New", but the price I think is on the cheaper end($100 per cell) so if that's worth it for a cell with 3.4V still then I'm ok with it. So why would a 3.4V cell be bad quality? This is my first time buying a...
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    Yes, they are advertised as new grade A cells. My DC power supply is rated for 10A max and each cell is rated for 100Ah. 1) so you think that the 0.9V cell is still salvageable by charging it alone? Will it's capacity be reduced having sat at such a low voltage? 2) If I do charge the 0.9V cell...
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    No cells are bloated and I do not smell anything. The measurement for each cell were: 3.4V, 3.4V, 3.3V, 0.9V.
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    New LiFePo4 cell arrived with low voltage. Is it bad?

    I just got my shipment of 4 "new" prismatic LiFePo4 cells rated at 3.2V each. However, one of them is only at 0.9V when I measured them. Is that cell permanently damaged or can I try to top balance it with the other cells and it'll be ok?
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    Overkill Solar 4S 12V 120A BMS M6 threaded Terminal wiring question

    Yes, thanks for clarifying! I will go with 2x 6 awg.
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    Overkill Solar 4S 12V 120A BMS M6 threaded Terminal wiring question

    Thanks for the "simple" answer! And yes, I'm interested in hearing about what you mean by appropriately sized wire. If it's what I'm guessing--I plan to have a max load of 110A on my 12V battery and according to this chart(https://conduit.site/tables/table-310.15-b-16.php) I should go with 2 #6...
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    Overkill Solar 4S 12V 120A BMS M6 threaded Terminal wiring question

    I notice that the 12V BMS from Overkill Solar has the option to include 3 soldered wires on each side of the BMS or an option to have 2 M6 threaded terminals on each side where the "C-" and "B-" wire holes are left empty. So if I pick the M6 threaded terminal option, will I need to solder a...
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