BQ40Z50-R2：BQ40Z50RSMR-R2

Hello,

Between the two forklifts, was there any difference in the usage trends over the three month period that could equate to this difference? What is the capacity of the cells in use?

Regards,

Anthony

你好，

電池都是在同一台堆高機上使用，兩台電持差異在安裝的位子不同，在檢查電池的SOH時，發現一台是98%，而另一台是88%。進一步檢查後發現，SOH較低的那一台，印表機安裝在堆高機的底部，DC電纜與堆高機的外殼接觸；而SOH正常的那一台，則將安裝在上方，並且直流電纜未接觸到外殼。

Ricky chen

Hi Ricky,

It is difficult to confirm whether this cable is the direct cause of this issue, however if the EMI is strong enough to induce a current, this can potentially effect the performance of the gauge.

Regards,

Anthony

Hi Anthony

Thank you for your reply^^

So, could EMI interference potentially cause abnormal SOH calculations?

this can potentially effect the performance of the gauge.->What gauge is this referring to?

Regards,

Ricky

Hi Ricky,

The SOH is calculated using a value known as SOH FCC, which is a FCC calculation based on a simulation at 25degC using the value specified by the SOH Load Rate. More information on this can be found below:

Based on the fact that this value is calculated from a simulated FCC value and not the FCC value calculated from the external measurements of the gauge, I believe this would be unlikely to have this much variation from EMI. Can you please confirm that the SOH Load Rate is the same in both of these gauges?

Regards,

Anthony

Hi Anthony,

你說電磁干擾（EMI）強度足以誘發電流，可能會影響儀表的性能,我想知道儀表如何影響電池的SOH計算?

我們經由實驗,已經確定noise干擾會影響電池SOH的計算,那麼noise干擾電池SOH是如何影響?(是影響Impedance Track Algorithm計算嗎?還是有其他以饗?)

是否有相關的資料可以提供給我?

請再回覆 感謝你 

Hi Ricky,

Since the SOH value is calculated based on a simulated value calculated by the gauge, I do not believe that EMI would have a direct effect on the calculation of the SOH. When these values are read out, is there still noise interference that could be contributing to the communication lines that could give a bad read? Is this read out still available if the noise interference is taken away?

Regards,

Anthony

Hi Anthony

我們的電池都是在同一台堆高機上使用，兩台電池差異在安裝的位子不同，在檢查電池的SOH時，發現一台是98%，而另一台是88%。進一步檢查後發現，SOH較低的那一台安裝在堆高機的底部，有跟DC電纜與堆高機的外殼接觸；而SOH正常的那一台，則將安裝在上方，並且與直流電纜未接觸.

在另外一台堆高機也發生同樣的情形,所以我們認為是DC電纜與堆高機的外殼接觸產生了EMI,

你曾經說過電磁干擾（EMI）強度足以誘發電流，可能會影響SOH計算錯誤，是否有相關的資料可以提供給我?

Hi Ricky,

Sorry for the confusion, when I stated that it would effect the performance of the gauge, I meant the calculations and tasks the gauge performs based on direct measurements from the system that could be effected by a false current from EMI. Since the SOH is based on a simulated value, I do not believe that the SOH would be directly effected by a false current.

Regards,

Anthony

嗨!安東尼

我們有測試cell校正為誤差(分別是100mV,200mV,300mV) (Gauge ADC voltage > Real  voltage)

並且將BAT pin voltage與Pack pin voltage校正為相同電壓

再去跑循環 3cycle

想請教:

1.為什麼Cell電壓下降100mV再改完Cell電壓後, 還沒有做Learning, RA TABLE就已經有變動了,SOH明顯變化??

2.為什麼Cell電壓下降300mV的在調整電壓後RA TABLE並沒有變化,  Learning 3CYCLE後,SOH只出現一點點變化,沒有像100mV有這麼明顯的變化??

3.為什麼Cell電壓下降200mV的在調整電壓後RA TABLE並沒有變化,  Learning 3CYCLE後,SOH沒有變化??

這些結果奇怪,100mV SOH會變化,  300mV SOH會變一點點,  200mV SOH都不會變

 請再回覆,謝謝!

Hi Ricky,

Would it be possible to receive the log and .gg for each of these situations so we can look more into what the cause might be?

Regards,

Anthony

JRM01-2412090002 -SATO UR18650NSX-4S1P(SOC異常)-不良退貨測試報告1230.zip

Hi Anthony

 我已將我的的實驗報告壓縮,請看報告(附件一 ESD實驗)及(附件二 100mV Cell壓差)

請幫忙回覆

謝謝

Hi Ricky,

This is difficult to determine a root cause without the full bqStudio log file data of each of these situations, however based on how each of them are described:

1. Since a learning cycle has not been completed on this unit, then it's performance is going to have abnormalities in it's calculation. The SOH is heavily dependent on the SOH_FCC value, which is a simulated FCC value based on how the gauge is configured along with other values from the gauge, such as Qmax. If the Qmax is not accurate since learning has not been completed, this value could be incorrect. In regards to why the resistance has changed, we would need more details on the load being applied in discharge to cause the resistance updates, along with the previous resistance values.

For the resistance update not occurring on #2 and #3, this could be due to the initial resistance values being different than #1 since a learning cycle has been completed. If the open circuit voltage at the time of the resistance update is greater then what is currently defined within the gauge, this will produce a negative resistance calculation and disable the resistance update. This can be caused by too little of a discharge load being applied.

Regards,

Anthony

再現實驗GG檔資料.xlsx

Hi Anthony

附上實驗的GG file數據

在查看ESD測試後的GG檔案時，我注意到Life times的Max Voltage（電池電壓歷史記錄）約在4450mV左右。通常的歷史記錄顯示約為4170mV，因此可以推測這是由於噪音導致電池電壓被抬高（即測量儀IC的讀取錯誤），從而使得Ra值變大，最終導致SOH下降，是否是SOH快速下降的可能原因?

Hi Ricky,

Thank you for sending that file, however I am not able to access the additional files contained in that excel sheet.

RICKY CHEN said:

When I was looking at the GG file after the ESD test, I noticed that the Max Voltage (battery voltage history) of Life Times was around 4450mV. The usual history shows about 4170mV, so it can be inferred that this is due to noise causing the battery voltage to be raised (i.e., the reading error of the meter IC), which increases the Ra value and ultimately causes the SOH to drop . Is this the possible reason for the rapid drop in SOH?

Is the Lifetime Max Voltage around 4170mV when the ESD Test is not completed? How is the ESD test being completed in this situation?

Would it be possible to see the Ra Table from the gauge before and after the ESD test is completed?

Regards,

Anthony

Hi Anthony

Ra Table(Please see the attachment).

Hi Ricky,

Can you please confirm that the RA Tables on the right of this excel are before the test and the tables on the left are after the test? If so, it seems like in the majority of the situations, the cell resistance seems to decrease or stay the same rather than increase.

Regards,

Anthony