diy solar

diy solar

Help!! BYD 24v battery scc voltage setup

gpower07

New Member
Joined
Apr 25, 2020
Messages
155
I want to charge the battery up to 90%. What is the voltage setting?? And also float, boost setting. Thank you
 
Is this a BYD used pack? There are many threads on this... the jist is, figure at best you are getting 26V in them... they will not charge to 100%, you will just waste watts trying.
 
Is this a BYD used pack? There are many threads on this... the jist is, figure at best you are getting 26V in them... they will not charge to 100%, you will just waste watts trying.
Yes..used. 26 max and what is the disconnect?
 
2.5v per cell, so, 20V some are setting it to 3/cell or, 24 to eeek a bit more cycles out of them
 
Yes..used. 26 max and what is the disconnect?
In my experience, and that of many others the BYD batteries settle at approx. 26.4 after charging. Bulk charge set can be anywhere from 27.2 to 28.8, depending on how hard you want to push them. I go with a conservative profile, due to their used condition and unknown longevity. I also float at 26.6, as I have significant loads throughout the day. Here's a good thread for an expanded discussion on these batteries:
 
The thread above is in great part about the pre-assembled units with BMS from BigBattery and TechDirect. If you are using the raw BYD battery many additional threads are on the forum - search for BYD battery - your selection of BMS and charging specs/usage will be a big factor in your satisfaction with the BYDs.
 
26 is not high enough - did you mean 28? That is my selected max charge V. It settles back to 26.4v like others under light load, but it spends a very long time at 26.2 to 26.4.
 
I changed it to 28. Look like water damage?
 

Attachments

  • Screenshot_20200524_000621_com.android.gallery3d.jpg
    Screenshot_20200524_000621_com.android.gallery3d.jpg
    44 KB · Views: 48
I changed it to 28. Look like water damage?

Might be an overheating problem from the previous commercial installation.

I have one pack that has melted insulation on the neg bus bar. Several have discoloration similar to yours. They still work nominally though.
 
I have a bunch of these byd's, all have the discoloration on the negative buss bar. My Byd's are playing nice with each other at 27.2v absorbtion for 5 min and constant float at 26.9v all day on solar. I have no bms, they are staying 20-60mv between cells.
 
I have a bunch of these byd's, all have the discoloration on the negative buss bar. My Byd's are playing nice with each other at 27.2v absorbtion for 5 min and constant float at 26.9v all day on solar. I have no bms, they are staying 20-60mv between cells.
Glad I ran across this post. I have 4 of them and I had been wondering how closely I should be trying to get these cells balanced. So far 43mv is the worst I have seen and one battery is at 7mv. Still working on getting them all more closely balanced to each other before I put them into service.
 
Glad I ran across this post. I have 4 of them and I had been wondering how closely I should be trying to get these cells balanced. So far 43mv is the worst I have seen and one battery is at 7mv. Still working on getting them all more closely balanced to each other before I put them into service.

That's a good idea.

The cells will go progressively farther and farther out of balance as they reach overcharge and undercharge states to the point where single cell damage can occur.
 
That's a good idea.

The cells will go progressively farther and farther out of balance as they reach overcharge and undercharge states to the point where single cell damage can occur.

I let my Chargery work on them for three days and got it down to the worst one being 17mv out of balance and the other 3 were all down to 7mv or less. May have improved more with more time but I had to move them into the bay of my bus where they will be put into service. I got my ISDT T8 Battgo and an ISDT parallel adapter today. I will be able to charge charge all four at once and then shifts have it switch to a 2amp balance charge when it reaches the voltage I set for the batteries.. I will rig a power source for it and let it charge and balance them while I finish up the install of my new 24v 4,000w inverter, the solar charge controllers and all that jazz. Hopefully they will be all balanced and I will have them in parallel for a bit to let them all even out even more and then I will put them into service.
 
I would think it will be fine. I would watch the delta (voltage difference) between it and the other cells to see if it is out of whack at the high or low voltage ends of the pack.
 
Back
Top