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Top Balancing LiFePo4 Cells using a low cost benchtop power supply.

Top Balancing LiFePo4 Cells using a low cost benchtop power supply. 2023-09-03

Thanks
You have put together a lot of valuable resources for this community! Thank you!
Legendary!
Thanks for putting this together!
This is very useful for my cells once I receive my power supply
Spectacular resource. As I am in the process of upgrading my battery bank to LiFePO4 I feel like this is better than gold. Well, as it should be. It’s information I really urgently need! The most valuable commodity in the world! Right?
Nice, good job
Thank you, very well explained.
Please place greater emphasis on the actual need for fabricating improved leads, how crappy the factory ones are, and that they may cause an already long process to be 2-3X as long. Include wording to indicate the following: 1) "Cells may ship as low as 30% charged. If you have 4X 280Ah cells, that's 0.7 * 4 * 280Ah / 10A = 78.4 hours of charging at 10A."; 2) at these low charge currents, cell voltages may barely budge for days at a time. Don't be surprised if you don't see voltage increase for very long periods of time. If you're still showing current on the power supply, and there is no heat or swelling, it's still charging."
Wow thanks for all the information in one place !
i found these errors in page 2:
"then you are more likely to get BMS High Voltage cut-offs with a 150V delta. However, if the charge voltage is going to run at a conservitve~3.5V/cell"
must be 150mV not 150V
and conservative not conservitve
FilterGuy
FilterGuy
Thanks!!
Definitely helpful
very help dude, thanks for going to all that effort for all of us. budding lipo builders
Very nice! Only one appreciation, maybe is my fault, but when precharging the cells (wired in series) the first cell with the positive connected to the source is getting 3,65 pretty before the others (the others are at 3,40), when the power source is of, all the cells are at 3,40. I'm doing something wrong?!
FilterGuy
FilterGuy
No..... You are not doing anything wrong. We know the cells are not ballance and one will hit 'full' first. It just means that cell is further out of balance than the others. It also means that once you put them in parallel, it will take longer for them to get up to 3.65 because the other cells are not as well pre-charged.

Some folks will say that .25 volt difference is too great to put them in parallel.
Personally, I would not worry about it. However, if you are concerned, start top balancing the other cells till they get up to 3.5 or so and then add the last cell in.
Thank you for taking the time to teach us yet again! This makes sense to me!
Thanks for the tips ;)
OUtstanding!
Great information! I will be using this tutorial when top balancing my batteries.
Thanks
Well done, very thorough, this has helped me tremendously, many thanks
... THANKS .... :)
HOLY CRAP!!! This is AWESOME! I could not have found this at a better time as I am looking for help on doing exactly what you describe here. I am now going to order my variable DC power supply right now. I'll look at the power supply you recommend and compare it to what I am considering.

By the way, I like the Alfred E. Neuman avatar.
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