And Now I wait

coil1002

Solar Wizard
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Nov 10, 2019
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61
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Wa State
20210720_231720.jpg
And Now I wait for this to finish top balancing. These cells where matched but in two groups of four. It took a day of charging with a small charger to get them in range of each other
 

MisterSandals

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Nov 5, 2019
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Those cells are at the top of there charge curve, the cells resistance would be more the current limiting factor I would think.
Yea, see now you were near the end at 3.5V, now 3.6V. It won't be long until you get there.
What is your stopping point? <1A?
 

MisterSandals

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While you're waiting you should label your cells. I recommend using letters (A, B, C...) because the cell positions in the battery are numbers.
Also, put some red tape or big +/- on your cells. Its super easy to assume the black terminal is the negative on the cells when you aren't vigilant.
 

Northernchateau

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Apr 14, 2021
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Worth, NY
I think top balancing batteries is like watching paint dry.
It's one of those things you need to do but you need to set your charger and walk away.
 

ken morgan

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May 11, 2021
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589
I think top balancing batteries is like watching paint dry.
It's one of those things you need to do but you need to set your charger and walk away.
You are entirely correct... that being said

Admit it you were freaking out the entire time your first pack was top balancing and went back and forth repeatedly for fear of damaging your investment... :)

I know I sure as heck did. and I had to drive 90 miles one way each time. ha ha ha I was so worried i drove back three times in one 10 day period before I finally said screw it and just closed my eyes and hoped/wished/prayed that nothing would blow :) midway through the second week they finished and I came back to find the charger in standby and the cells had topped and then dropped back to 3.51 or so. (20Kw 48 volt bank).
 

Northernchateau

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Worth, NY
You are entirely correct... that being said

Admit it you were freaking out the entire time your first pack was top balancing and went back and forth repeatedly for fear of damaging your investment... :)

I know I sure as heck did. and I had to drive 90 miles one way each time. ha ha ha I was so worried i drove back three times in one 10 day period before I finally said screw it and just closed my eyes and hoped/wished/prayed that nothing would blow :) midway through the second week they finished and I came back to find the charger in standby and the cells had topped and then dropped back to 3.51 or so. (20Kw 48 volt bank).
I protected my investment by setting my charger to 3.55 volts when I was not there.
Once I was there to monitor it with a separate volt meter I re-set my charger to 3.65v
 

ken morgan

Solar Addict
Joined
May 11, 2021
Messages
589
I protected my investment by setting my charger to 3.55 volts when I was not there.
Once I was there to monitor it with a separate volt meter I re-set my charger to 3.65v
I started with a non adjustable 3.65 lifepo4 specific charger, and being that I had no clue as to its actual, quality I am as freaking out during the first week. :)
 

coil1002

Solar Wizard
Joined
Nov 10, 2019
Messages
61
Location
Wa State
While you're waiting you should label your cells. I recommend using letters (A, B, C...) because the cell positions in the battery are numbers.
Also, put some red tape or big +/- on your cells. Its super easy to assume the black terminal is the negative on the cells when you aren't vigilant.
Good idea. I had already Marked positive and negative its hard adjusting to block positive after a lifetime of it being the opposite. There where too many close calls no sparks but enough confusion that I marked them.
 

coil1002

Solar Wizard
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Nov 10, 2019
Messages
61
Location
Wa State
The results are in 117 AH I am actually pretty pleased considering I discharged at around .5c I just hooked it to the solar inverters and ran the house until it got to low voltage cut off of 21 v. So all and all not bad at all I think. I got these off a vendor on ebay with shipping to my door they where $85.50 per cell and I had to bargain to get that price. But they where US stock and got here in a week. So I am ok with that.
 
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