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From what I remember, there are three temp sensors on the BMS (two are internal) and the temp displayed on the main page is that of the highest reading sensor. By dipping the battery temp sense in ice, the temp displayed will be that of one of the internal sensors.

Andy from off grid garage on YT has done a lot of testing of LiFePo4 cells and his videos provide a lot of insight as to characterists of the cells. There is a lot of useful info there regarding charging.

Battery tail current is a user defined parameter but I think you are referIng to the battery charge current as the battery nears full charge? Either way, the charge current is not “determined”, it is measured by the shunt and the value sent to the charge controller. If that value is less than...

Personally, I think that is the beauty of the VE.smart connection system. It is all done via Bluetooth and a more complex system using VE direct and a cerbo GX or similar is not required.

Agreed.

Sorry if I have this wrong but you seem to have missed the point. Terminate charge using a tail current strategy in a in service system is only feasible if the charger can monitor the actual current going into the battery. This is where a smart charger and smart shunt can work really well. Via...

Thanks, I was looking at the wrong charger. Correction, I was looking at the right charger (Blue smart IP22) but the manual makes no mention of ve.smart networking. However, it is mentioned in the features list.

Well, I have a 600Ah battery and I’ve set the tail current parameter to 1A (the max value you can set is 10A) and the absorb time is 15 mins. The charge current will drop below the 1A tail current setting before the 15 min absorb time has expired. I’m sure this strategy would work perfectly well...

If you don’t use the tail current feature, when does the charger go to float? I agree the feature is more useful for lead acid batteries as using a fixed or even adaptive absorb time is just a guess as to what the battery actually needs but terminating the absorb period on a LifePo4 battery...

Sorry but I’m still not clear on one thing. Does your mains smart 12/30 support VE.smart networking and goes it have the tail current parameter?

SOK have to push the charging parameters to the absolute max for the cells to achieve the claimed Ah capacity. Higher capacity claims sell more batteries.

Agreed. I also think it’s wrong to claim this charger is suitable for LiFePo4 chemistry when there appears to be no provision for low temp charge cut off protection.

The “tail current“ along with “Charged voltage“ and “Charge detection time” are parameters used by the smart shunt to determine when the battery is considered fully charged. When all the conditions are met, the SoC will be reset back to 100%. (Synchronized). The condition to be met for...

Not sure I would agree here. In photo 5 the cells are discharged and at rest. If there were a poor bus bar connection between the cell pairs 2 and 3, the cell voltage would have recovered with no load. Since the voltage has not recovered, I doubt it’s the bus bar.

Since the difference between the two is 0.3%, I’d say they are both equally accurate. The solar charge controller charges the battery to the same state of charge each time. If the BMS or smart shunt were inaccurate, the SoC would drift either up or down.

I’ve seen this before. It explains the difficulties in tracking the actual capacity of the battery. The OP had a discrepancy between the %SoC and consumed Ah’s. SoC is calculated using various parameters. By setting charge efficiency and Peukert to unity, it might help identify the problem.

The BMS says the SoC is 90%.

1.00 and 100% works for me

Well, after 30 days charging to 90% with no syncing, my smart shunt reads 90.3%.

I’ve seen it but not had any reason to change it.

Where can I find this information? I looked on CATL website but it was all corporate stuff

RJ-lithium got back to me and said the Gobelpower web site is not to be trusted. Having pinged Gobelpower a few times, their responses have not given me much confidence in their QR code decoder and I’m more inclined to believe RJ-lithium who have suggested that I capacity test the cells myself.

Does anyone know if this Gobelpower decoder is accurate?

How reliable is this decoder? I ask because yesterday I put in a QR code and today I put in the same QR code and got a different result

I wish I’d seen this thread earlier. I’ve just received 16 302Ah cells from RJ-lithium but the QR codes reveal they are 280Ah cells. I’ve contacted RJ-lithium and am waiting for a response.

I’ve just received 16 302Ah cells from RJ-lithium but decoding the QR codes, they reveal the cells are in fact CATL 280Ah unit manufactured in July/August last year. I’ve pinged RJ-lithium about this and we’ll see what they come back with.

I’ve made 2 home made trackers. Each tracker carries 2kW of panels. The frames are home made from steel tubing and they are both single axis trackers. 36v linear actuators normally used for large satellite dishes were used to manipulate the array. I designed and built the electronics. The first...

You can use the smart feature of your MPPT and BMV so that the MPPT uses the current reading from the BMV shunt so MPPT can see the actual current going into the battery. If you've a Victron smart charger, can it not do the same?

Do you have a screen shot of your BMS when the pack voltage is at 14.3V? At 13.3V, cell imbalance is not going to be very obvious.

Have you a cell imbalance? What is the cell cut off voltage set to? You mentioned earlier a voltage discrepancy between the Tracer and the battery monitor. At a charge current of 14A, you’re getting a 0.2V difference. Have you confirmed the voltage differences with a DVM? Perhaps your cables...

If the cells are all at the same voltage when the SCC drops back to float then yes, there will be no balancing. It is when there is an imbalance and one cell is higher when the SCC drops back to float that the balancing occurs. I’ve arrived at the setting I have by observation and experiment and...

I’m off grid and my system is in use 24/7. My batteries normally reach absorb voltage by mid day, 30 minute later the SCC goes to float. If I set the balance threshold to say 3.50v per cell and the absorb voltage is 3.55v per cell the balance time is only about 45mins (30mins absorb and 15mins...

Personally I’d like to see top balancing start at the float voltage.

This is nonsense. He says if you get a high voltage disconnect at say 14v due to cell imbalance you should charge to 14.2-14.4v to balance them. How do you get to 14.4v if you get a BMS disconnect at 14v?

Hi James, If the link Bud has posted is indeed your SCC, it seems to be protected against just about every eventuality. Into a 12V battery, a 260W solar panel could easily deliver over 20A but the controller will limit the current to it's max rating of 20A. The symbol on the display might lead...