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Alibaba LiFePo4 batteries

Note:
I don't know if you have followed the posts about damaging the threads in the cells..... but be very careful about putting screws or posts in and out as you switch back-and-forth between serial and parallel. Ideally, the first thing you do with new cells is put studs in with red locktite and never take them out again.
 
should I disconnect it and charge them up and than go back to top balance or should I just leave it alone and let do its job?
That is a personal choice. Either way works. Just be careful of the threads on your terminals if you are changing things around.
 
That is a personal choice. Either way works. Just be careful of the threads on your terminals if you are changing things around.
I'm not touching them right now just the lead wires going to the cells.
 

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It took about 20 Hours for my battery, charging at around 15A.
 
That is not as much change as I expected...... but that just confirms the SOC of the cells is still pretty low.

BTW: 50% SOC is pretty typical for how cells are shipped.
Well I cant wait till it's done, they should give me alot of storage.
 
3.65 is fine but not necessary. Just keep an eye on it and make sure the voltage at the battery terminals does not exceed that. Don't rely on the meter that's on the power supply...
Ok another question, my charger is reading 3.61 but my batteries are reading all different numbers like 3.52, 3.35. Could that mean I could have a bad cell?
 
Ok another question, my charger is reading 3.61 but my batteries are reading all different numbers like 3.52, 3.35. Could that mean I could have a bad cell?
That is kinda normal. It tells me you have a voltage drop on the power supply leads. You also have voltage drops between cells.

You can leave it alone and the voltages will all ballance out as the cells charge and the current goes to zero.

However, the voltage drops are indication of resistance and power loss. The only problem with this is that it means it will take longer to reach full charge. My advice is to leave it alone and be patient. However, if you want to do something here are two things to do:

1) Build better power supply leads (Particularly if you have alligator clips).
2) make sure the positive power supply lead is on one end of the parallel bank of cells and the negative power supply lead is on the opposite end.
 
That is kinda normal. It tells me you have a voltage drop on the power supply leads. You also have voltage drops between cells.

You can leave it alone and the voltages will all ballance out as the cells charge and the current goes to zero.

However, the voltage drops are indication of resistance and power loss. The only problem with this is that it means it will take longer to reach full charge. My advice is to leave it alone and be patient. However, if you want to do something here are two things to do:

1) Build better power supply leads (Particularly if you have alligator clips).
2) make sure the positive power supply lead is on one end of the parallel bank of cells and the negative power supply lead is on the opposite end.
Ok this is how I have it setup, both have a bronze ring on them and I have 100 amp fuse on the positive lead. I can for the next battery to have the negative on the other end or buy a bigger charger.
 

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Ok this is how I have it setup, both have a bronze ring on them and I have 100 amp fuse on the positive lead. I can for the next battery to have the negative on the other end or buy a bigger charger.
Also the wires are 2 gauge
 
That looks good.... you can leave it like that and everything will work.

Here are two things I would do differently...but are not required for a successful Top Ballance:
1) Get rid of those extra bus-bars and hook the leads directly to the Cell terminals. Those extra bus bars do nothing but add resistance.
2) Move the negative connection to the cells to the opposite end of the bank of cells.
 
That looks good.... you can leave it like that and everything will work.

Here are two things I would do differently...but are not required for a successful Top Ballance:
1) Get rid of those extra bus-bars and hook the leads directly to the Cell terminals. Those extra bus bars do nothing but add resistance.
2) Move the negative connection to the cells to the opposite end of the bank of cells.
Heard that and thank you! I'll do that for my next battery after this one is done. Shouldn't be much longer almost done.
 
That looks good.... you can leave it like that and everything will work.

Here are two things I would do differently...but are not required for a successful Top Ballance:
1) Get rid of those extra bus-bars and hook the leads directly to the Cell terminals. Those extra bus bars do nothing but add resistance.
2) Move the negative connection to the cells to the opposite end of the bank of cells.
Can you also help me on where I can buy 6mm 1 inch studs for my cells?
 
Do a search of "6mm x 25mm stainless grub screws" (25mm is approx 1")

This is one of many results that came up when I just did the search

Note, be sure to get Flat Point or Cup point. (Don't get ones with a point on them)
 
Do a search of "6mm x 25mm stainless grub screws" (25mm is approx 1")

This is one of many results that came up when I just did the search

Note, be sure to get Flat Point or Cup point. (Don't get ones with a point on them)
So I'm going to buy new wires for my batteries and wondering getting them from a hardware store or audio store are different? I'm planning on buying 2 awg wire.
 

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