My 12v lithium battery was fully charged and showed 100% SOC when I connected loads. No chargers was connected in a 14 hour period. This morning soc was 77% with about 25 amps consumed. I connected my 240w solar panel this morning. (Using a 12v 30amp Victron mppt)It is overcast and changing at a net positive current of 2amp (27w) Within minutes of connecting the solar panel the soc shows 100%. This should not be? Can someone advise.
Check all negatives are on the correct side of the shunt, loads on the load side and just the battery(s) on the battery side.
Check you system configurations on the shunt for absorption voltage, tail current and charge connection time. They should be something like this...
Litium batteries all use a BMS that monitor the cells inside your battery.
The SOC (State Of Charge) is calculated from measuring the power flowing in or out of the battery and comparing that to the stated battery capacity.
If you have one or more cells that in not well balanced to the rest it will jump up in voltage very fast. The BMS will pick this up, stop charging and declare that your battery is full - which it is as you cannot add any more power to the battery. The difference between the expected energy that can be stored and what can actually be stored would indicate the health of your battery (sometimes calls State Of Health SOH).
To fix that you need to balance your battery's cells. Your BMS should have balancers build in to do this, but in most instances they work with small currents while you charge your battery with much higher currents. To give them more time to do their job, set your system to Keep Batteries Charged, reduce the charge current and lower your charge voltage. Give it a week or two depending on your battery capacity and it should be balanced again.
I recommend you limit the charge current to 200mA-500mA per the amount of cells in your battery and reducing the charge voltage by 1V and then adding 0.1V each day until you get back to the original values. Check the DVCC settings on how to set these limits.
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Configuration is your issue... Take a look at the Victron tech tab videos. They will help you understand your equipment.
https://www.youtube.com/results?search_query=victron+energy
Specifically this video or this one
Your charge voltage is too low. As soon as the voltage reaches 13.2v, current is around 2A for 3 minutes the system will sync the SOC and say it is full. As you are on solar, the current can be very low, and thus you get an early synchronisation.
You need to increase your charge voltage to something more like 14.2v.
This is the settings and battery specs. What do i do for it to reflect the correct soc?
The install is correct. Louis, never had any problems with the battery charging from victron dc and victron ac chargers. I suspect some of my settings is incorrect. Does the charged voltage in settings remain the same for all the different victron chargers, ie dc, ac and mppt?
It is normal for cells to get our of sync/balance over time. If you use the battery hard that can happen sooner. So you just need to do some maintenance time to get it fixed.
The charged voltage of 13.2V is too low for this battery. That is 3.3V per cell and the internal balancers normally only start when a cell go higher than that. This battery want to charge at 14.4V and then float at 13.8V which is 3.6V and 3.45V per cell.
I would suggest you change your charge voltage to 13.6V and keep it there for 3-5 days. Then you can increase that each day by 0.1V until you get to 14.4V. The slower you go the better. Once you reached 14.4V you can reduce that again, but don't go lower than 13.6V so that the balancers can work each cycle.
This is also a plug in replacement so we have no idea what the cell balancing is. This map not be a call issue.
It showed 77% SOC having had 25A removed. So looks like charging is OK, battery is performing correctly, but the SOC synch is happening too early.
