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diy solar

diy solar

My build thread

They will, but I don't know how far off they will be at the beginning of balancing.
This is why I was running the test, for as long as possible.
 
Well, things never go as planned.
I have to do a service call today. So I will have to delay the charging.
Because I want to be here to monitor the balancing.
No big deal. I'll still get it done. But I was hoping for a relaxing day off.
It's always something. lol
 
Balancing is just beginning (3.45v).
Largest delta is currently 122 mv. (Oldest battery)
I'm sure it's will expand, as it starts climbing the knee. But so far, I can't complain.
 
That delta isn't a runner, it's a stragler.
Average cell voltage in the battery is 3.519v and the stragler is at 3.348v
My current batch of cells came in, and this time I ordered a group of 20 cells: 16 for the next pack-build, and 4 spares to allow swapping out any outliers from a couple packs. I put a post-it note on any pack that shows an odd-ball cell at high or low SOC and note which cell it is, the delta etc. Now with some spare cells I will try swapping around and then see how it does. Later the four crappiest cells can be made into a portable 4s pack for the MPP 1012 mobile set up.
 
My current batch of cells came in, and this time I ordered a group of 20 cells: 16 for the next pack-build, and 4 spares to allow swapping out any outliers from a couple packs. I put a post-it note on any pack that shows an odd-ball cell at high or low SOC and note which cell it is, the delta etc. Now with some spare cells I will try swapping around and then see how it does. Later the four crappiest cells can be made into a portable 4s pack for the MPP 1012 mobile set up.
That stragler already has a post-it note on it. lol
I noticed that it was struggling before.
 
That delta is at 235mv now.
It won't get any worse, as bulk charging is complete (57v).
Now, I'll just see how long it takes to balance.
The rest of the batteries are doing great.
 
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That is the point, for what it costs for meter charges, it might be cheaper to unhook from grid.

The Kwh used can be expensive. In November, we used 18 Kwh from grid and in December even with 3 weeks of fog, we used 404 Kwh from grid and that is mainly due to laundry when in grid bypass. That might be all the grid power we need until next November/December.

Correction, I see tonight we only used 134 Kwh from grid in December, the 404 Kwh was in the column to the left in SA and is Battery Discharge for the month.

Using the example from that post, generator cost for fuel is $0.23/Kwh. Right now, I'm paying $0.17755/Kwh with a $25.08/month meter charge or basically $300/year.

422 Kwh would cost me $74.92 for the Kwh plus $300=$374.93 for the year. That comes to almost $0.89/Kwh. For the 422 Kwh/year, it would cost $97.06 for fuel using the generator. Can one purchase a generator and maintain it for $278/year is the question.
With the correct grid usage for the year of 152 Kwh, the cost would be $300/year for meter charge and $27 for the Kwh used comes to $327 per year. That makes the cost of grid power $2.15/Kwh.

Those are high priced Kwh.
 

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