Juanjo Madrid's cell replacement thread

[Juanjo Madrid]

I use 9.85 Diagbox, my dude is if I need wait until full discharge (0 bars) or only when start blinking (2 bars) when say "Wait for the charge warning lamp on the instrument panel to switch off then move on to step 2" previous middle year 2011 cars need three step, I need two because is 2012, the bigger difference is 3v83 to 3v91. I waiting to "electric station(LCD draw) or plug symbol lamps( red lamp) go off, and never happen, maybe need wait until not bars? only electric station lamp go to blink , if validate when blinked the error appears, afther say "disconnect from electric Network, put to off ventilation handler and the other knobs to off"

 

[MickeyS70]

I use 9.85 Diagbox, my dude is if I need wait until full discharge (0 bars) or only when start blinking (2 bars) when say "Wait for the charge warning lamp on the instrument panel to switch off then move on to step 2" previous middle year 2011 cars need three step, I need two because is 2012, the bigger difference is 3v83 to 3v91. I waiting to "electric station(LCD draw) or plug symbol lamps( red lamp) go off, and never happen, maybe need wait until not bars? only electric station lamp go to blink , if validate when blinked the error appears, afther say "disconnect from electric Network, put to off ventilation handler and the other knobs to off"

In order to deep discharge the battery you need to put the heater on max, turn on AC and set the fan to boost.

This will take a long time if you start with cell voltages around 3.9V…

 

[Juanjo Madrid]

Para descargar profundamente la batería, debes poner la calefacción al máximo, encender el aire acondicionado y configurar el ventilador al máximo.

Esto tomará mucho tiempo si comienzas con voltajes de celda alrededor de 3,9 V…

I will try next time with only one bar (LCD lamp blinking), Today need use the car and finally charge without do it, show 88 Km in the RR when full, I feedback when do it

 

[MickeyS70]

show 88 Km in the RR when full, I feedback when do it

That seems pretty good for a 2012 I-MIEV, looks like the cells you replaced weren't the ones with the lowest capacity, they just couldn't handle high currents?

You may therefore not see a significant improvement of the remaining capacity after a battery calibration.

 

[Juanjo Madrid]

That seems pretty good for a 2012 I-MIEV, looks like the cells you replaced weren't the ones with the lowest capacity, they just couldn't handle high currents?

You may therefore not see a significant improvement of the remaining capacity after a battery calibration.
.

Something strange happens after my maintenance attempt, today morning the charger stopped with 78% SOC, not all the bars appear on the dashboard and I tried several times to fill it but it was not possible, today in the morning it shows 62 km RR and when I see the voltage before starting, many cells are at 4.1V, some at 4.089 and the two LEV50N at 4.03 and 4.04V but the 78% SOC is in the OBDZero application. Now charging in my job the SOC is 81,3% and 0,18A /100W (look like is finalizing soon)

I will probably try to do the procedure again tomorrow, something is now telling the vehicle that the capacity and the bars do not match when I made the failed attempt of maintenance.

Yesterday, I tested the faulty LEV50 cell with a RC Lithium charger/discharger (long time at 2A max) and the measured capacity is similar to the second LEV50 cell I replaced (this one was fine but I took it out so I can compare between the bad one and the others that are still useful using this sample one), so I had to use the two LEV50N I bought, I think it is necessary to test them with a 2000W 12V inverter with high current request, will 100A be a good test?

Driving this morning I see the turtle with high demand again (spend more time to see the turtle, it's on my daily route), I see three other cells now with similar voltage, 2V8 to 2V86V

I have two CATL 93Ah plus the LEV50 that I replaced without being damaged, so next time I open the package I think I need to evaluate with the inverter test or a 5000W UPS that works with 36V, maybe it would be better to test 8 complete cells without disassembling all, adding externally the 2 CATLs that I have in the series of 8.

 

[MickeyS70]

Something strange happens after my maintenance attempt, today morning the charger stopped with 78% SOC, not all the bars appear on the dashboard and I tried several times to fill it but it was not possible, today in the morning it shows 62 km RR and when I see the voltage before starting, many cells are at 4.1V, some at 4.089 and the two LEV50N at 4.03 and 4.04V but the 78% SOC is in the OBDZero application. Now charging in my job the SOC is 81,3% and 0,18A /100W (look like is finalizing soon)

I will probably try to do the procedure again tomorrow, something is now telling the vehicle that the capacity and the bars do not match when I made the failed attempt of maintenance.

Charging stops once a cell reaches 4.1V, but this will only result in 100% SoC if the energy measured going into the HV battery equals the capacity value set in the BMU.
The only way to correct the discrepancy quickly is to to calibration.

Yesterday, I tested the faulty LEV50 cell with a RC Lithium charger/discharger (long time at 2A max) and the measured capacity is similar to the second LEV50 cell I replaced (this one was fine but I took it out so I can compare between the bad one and the others that are still useful using this sample one), so I had to use the two LEV50N I bought, I think it is necessary to test them with a 2000W 12V inverter with high current request, will 100A be a good test?

Max current (foot to the floor) is around 150A therefore a 2A discharge test is pointless, > 100A is certainly the way to go.

Driving this morning I see the turtle with high demand again (spend more time to see the turtle, it's on my daily route), I see three other cells now with similar voltage, 2V8 to 2V86V

Unfortunately that’s what happens if you replace the worst performing cells, others will take their place..

I have two CATL 93Ah plus the LEV50 that I replaced without being damaged, so next time I open the package I think I need to evaluate with the inverter test or a 5000W UPS that works with 36V, maybe it would be better to test 8 complete cells without disassembling all, adding externally the 2 CATLs that I have in the series of 8.

Use the CATL cells, don’t bother putting the LEV50 back, testing the cells externally is a good idea, you could even read out the cell voltages via CAN using the CMUs if you have an Arduino or similar..

 

[Juanjo Madrid]

La carga se detiene una vez que una celda alcanza los 4,1 V, pero esto solo dará como resultado un SoC del 100 % si la energía medida que ingresa a la batería HV es igual al valor de capacidad establecido en la BMU.
La única forma de corregir la discrepancia rápidamente es mediante la calibración.


La corriente máxima (del pie al suelo) es de alrededor de 150 A, por lo tanto, una prueba de descarga de 2 A no tiene sentido, > 100 A es ciertamente el camino a seguir.

lamentablemente, eso es lo que sucede si reemplazas las celdas con peor rendimiento; otras ocuparán su lugar.

Utilice las celdas CATL, no se moleste en volver a colocar el LEV50, probar las celdas externamente es una buena idea, incluso podría leer los voltajes de las celdas a través de CAN usando las CMU si tiene un Arduino o similar.

I was thinking of returning a LEV50 because it is better than others, I only have two CATL93 and 3 very clearly degraded cells, low voltage and high temperature, temporary solution of course. Yesterday I did the maintenance procedure, I confirm that the procedure is really possible with Diagbox V9.85 on Imiev cars. But after spending charging all the night at temperatures of 3°C, the charge indicator stopped at approximately 80% and a capacity of 20 Ah is registered in the BMU with the current Km, although it gave an error in step 2 and asked me to repeat Again, my mistake was not waiting for the end of the complete discharge, the complete discharge and charge take place on their own when the air conditioning is stopped, I thought that 20 Ah is not real, it indicates 72 km and three bars are still missing, the cells maximums do not reach 4V1 only 4V09 abd 4V08, now when starting the charge only enter a tiny current, I understand that it is balancing (again), but the indicator still wrong? I will try the process until I finish it without errors.

Traction battery total capacity with Diagbox show 2Ah more from 25.7Ah to 27.5Ah and 13.25 can be received.

 

[MickeyS70]

I was thinking of returning a LEV50 because it is better than others, I only have two CATL93 and 3 very clearly degraded cells, low voltage and high temperature, temporary solution of course.

Replacing cells in a degraded pack is like a game of ‘whack-a-mole’, regardless of how may you replace, different ones will show bad until you have swapped them all, I’m afraid..

, the cells maximums do not reach 4V1 only 4V09 abd 4V08, now when starting the charge only enter a tiny current, I understand that it is balancing (again), but the indicator still wrong? I will try the process until I finish it without errors.

Charging stops once one cell reaches 4.1V, but then balancing starts and the highest cells are ‘bled’ to reach the voltage of the lower ones, however because of the tiny balancing current this function eventually times out and this is what you see

Traction battery total capacity with Diagbox show 2Ah more from 25.7Ah to 27.5Ah and 13.25 can be received.

You need to finish the procedure without errors to get the indicator ‘fixed’
Btw one of the screen shots shows a 12V aux voltage of 11.6V (0%SoC) best to replace it altogether..