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Top Balance Charger?

Devin82m

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Dec 15, 2020
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Hello, I was wondering if anyone suggested a charger for top balancing my Fortune 100 Ah cells? I have a nice 4/15 Amp Victron for 12V and a bench power supply for electronics projects, I tried the Victron and realized it won't go below 12V. I tried the bench psu and set it for 4 Amps, it never seems to get the cells higher than 3.1V. Needless to say I'm not sure what to buy on Amazon that will allow me to top balance these cells with some good amperage and with protections for LiFePo4 cells. Any suggestions are welcome.
 
 
I followed Will's video, the only issue I saw is that after 24 hours the amperage never rose above 1.4 Amps even thought I set it to 4 Amps. Also the voltage only increased .1V. This was using my bench power supply set at 3.65V.
 
I followed Will's video, the only issue I saw is that after 24 hours the amperage never rose above 1.4 Amps even thought I set it to 4 Amps. Also the voltage only increased .1V. This was using my bench power supply set at 3.65V.

Did you adjust the voltage before you connected it to the battery ..... then leave it alone?
 
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You may have undersized leads from your power supply that are causing a voltage drop. It will work, but may take several days.

A lot of us run 10 AWG leads with ring terminals to minimize voltage drop.
Ah. I wondered if it's the leads, I have bigger ones I can use. So is it important to get them all to 3.65? Or will 3.31 work?
 
I followed Will's video, the only issue I saw is that after 24 hours the amperage never rose above 1.4 Amps even thought I set it to 4 Amps. Also the voltage only increased .1V. This was using my bench power supply set at 3.65V.

The guide is much more thorough, and it should be what you follow.

You may have undersized leads from your power supply that are causing a voltage drop. It will work, but may take several days.

A lot of us run 10 AWG leads with ring terminals to minimize voltage drop.

Yep. Classic crap connections.

@Devin82m,

PLUS, you need to charge AT LEAST 50Ah/cell, so at 1.4A, 50/1.4 = 35.7 hours PER CELL. If your cells are at 3.1V, then you may need to charge much closer to 100Ah.

Voltage movement will be so slow you will think something is wrong, but as I mentioned above, 35.7 hours per cell and possibly nearly double that.

If you have 4 cells, you may be looking at 215 hours of charging at 1.4A.
 
I followed Will's video, the only issue I saw is that after 24 hours the amperage never rose above 1.4 Amps even thought I set it to 4 Amps. Also the voltage only increased .1V. This was using my bench power supply set at 3.65V.
It's not an "issue" so much as you are seeing the VERY flat lithium charge profile. Better cables and connectors would probably help the amperage. Snoobler gave you a link that has pretty much the answer to all of your questions, I'd recommend reading it.
 
Thanks everyone, I whipped up some new cables with some 12 AWG I had a spool of and some ring connectors, that bumped up the amperage to 5 A and the batteries are now past 3.1. I was going to use some 1 AWG cables I had, but the the ring connectors were too big and made contact with each other on my bechn psu.
 
Thanks everyone, I whipped up some new cables with some 12 AWG I had a spool of and some ring connectors, that bumped up the amperage to 5 A and the batteries are now past 3.1. I was going to use some 1 AWG cables I had, but the the ring connectors were too big and made contact with each other on my bechn psu.
I'm glad that helped.
A lot of people seem to ignore the advice about better cables, and are puzzled why their supply is not putting out the amps it should, and turn the voltage up to get more amps.

I recommend the 10 gauge wire and 1/4 inch ring terminals because they are easy to find (either Amazon, Home Depot or Lowe's).
The 10 gauge crimp ring terminals are about the largest "common" size and the 1/4 inch size works great for the common M6 sized connectors people are needing. It really does make a difference, and usually reasonably priced.

Up to 3.4v it will seem like it's broken, once up above that it will take off like a rocket, so be sure your power supply is set to 3.65v while NOT CONNECTED. You don't want to be surprised with puffy cells. The good news is that with proper cables, up to 3.4v it should be able to supply max amps, over that it will taper the closer you get to 3.65v. Most power supplies will also accept 1/4 ring terminals if you unscrew the banana jack outer insulation, put on the ring terminal, then put the cover back on and screw it down to get a good connection. Some don't unscrew all the way (looking at you Riden) and thus you have to use spade terminals.
 
I'm glad that helped.
A lot of people seem to ignore the advice about better cables, and are puzzled why their supply is not putting out the amps it should, and turn the voltage up to get more amps.

I recommend the 10 gauge wire and 1/4 inch ring terminals because they are easy to find (either Amazon, Home Depot or Lowe's).
The 10 gauge crimp ring terminals are about the largest "common" size and the 1/4 inch size works great for the common M6 sized connectors people are needing. It really does make a difference, and usually reasonably priced.

Up to 3.4v it will seem like it's broken, once up above that it will take off like a rocket, so be sure your power supply is set to 3.65v while NOT CONNECTED. You don't want to be surprised with puffy cells. The good news is that with proper cables, up to 3.4v it should be able to supply max amps, over that it will taper the closer you get to 3.65v. Most power supplies will also accept 1/4 ring terminals if you unscrew the banana jack outer insulation, put on the ring terminal, then put the cover back on and screw it down to get a good connection. Some don't unscrew all the way (looking at you Riden) and thus you have to use spade terminals.
Yeah, and I knew better too. I was at HomeDepot earlier today and didn't think to buy some 10 gauge while there, I had some but gave it to someone that needed it. I may have something else, I need to look. Actually, I think I have some wire for house wiring that I could use too. Yeah, I unscrewed the terminal nuts and got my rings on and they are rated for 12-10 gague, so properly sized. Thanks for the tip about changing the voltage before connecting, I thankfully did that, but I go in there and check in about once an hour. I'm paranoid about starting a fire. Of course right now we are having heat waves and I moved my roll around air conditioner to my daughters room from my office so my office was pretty toasty, I may take a break from it until it cools down or Monday when I move the AC back for work, heh.
 
Yeah, and I knew better too. I was at HomeDepot earlier today and didn't think to buy some 10 gauge while there, I had some but gave it to someone that needed it. I may have something else, I need to look. Actually, I think I have some wire for house wiring that I could use too. Yeah, I unscrewed the terminal nuts and got my rings on and they are rated for 12-10 gague, so properly sized. Thanks for the tip about changing the voltage before connecting, I thankfully did that, but I go in there and check in about once an hour. I'm paranoid about starting a fire. Of course right now we are having heat waves and I moved my roll around air conditioner to my daughters room from my office so my office was pretty toasty, I may take a break from it until it cools down or Monday when I move the AC back for work, heh.
12 gauge is good enough, I wouldn't bother since you said that is what you are using. If you are going to snag some ring terminals and spot a good deal on fine stranded 10 gauge, then yeah.

Most cheap power supplies have cheap alligator clips and banana jacks that just have too much resistance. The ring terminals on each end and a better wire make a difference.
 
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