JK BMS SoC self-learning and elapsed time reset.

[LMF5000]

I have a JK_B1A8S10P (bought to save an old LiFePO4 pack of unknown capacity, probably around 40Ah and 7s so 22.4V).

It's running great so far but being new to JK I have a couple questions that I can't seem to find the answers to in any documentation or forum posts:

1. Is there any way to reset the elapsed time counter in the title bar of the app (the one that says 13H44M50S. More curiosity than necessity, but I wasted rather a lot of time on the test bench and was wondering if there was a way to start the counter from zero.

2. Does the BMS learn real battery capacity and eventually change the "battery capacity" value to match the real one? I've only done one partial cycle so can't tell for now.

3. Is there a way to monitor the cell parameters from a distance? Bluetooth range doesn't even make it to the adjacent room and there doesn't seem to be a pc app. I'm pondering leaving an old phone in the room with the battery and using an app like airdroid to see the numbers on the phone - but surely there's a more elegant solution?

4. At the top of the app I have an entry called "Charg. Plugged: Not Plugged" (right after heating status. Does anyone know what charger it's referring to? The item doesn't change when I charge or discharge the battery.

 

[Marv21]

->3:
There is an Github project for an ESP32. That will collect the Data via Bluetooth and publish it via Wlan (MQTT etc).

 

[Steve_S]

I have a JK_B1A8S10P (bought to save an old LiFePO4 pack of unknown capacity, probably around 40Ah and 7s so 22.4V).

It's running great so far but being new to JK I have a couple questions that I can't seem to find the answers to in any documentation or forum posts:

1. Is there any way to reset the elapsed time counter in the title bar of the app (the one that says 13H44M50S. More curiosity than necessity, but I wasted rather a lot of time on the test bench and was wondering if there was a way to start the counter from zero.

There is no way to do that.

2. Does the BMS learn real battery capacity and eventually change the "battery capacity" value to match the real one? I've only done one partial cycle so can't tell for now.

The BMS requires a couple of cycles to learn. But there is a glitch on the BMS stating it has 100%. Andy just put out a video (hack) on how to sort that. See here:

3. Is there a way to monitor the cell parameters from a distance? Bluetooth range doesn't even make it to the adjacent room and there doesn't seem to be a pc app. I'm pondering leaving an old phone in the room with the battery and using an app like airdroid to see the numbers on the phone - but surely there's a more elegant solution?

There is no PC App for the original JKBMS'. They use BlueTooth BLE which is very limited range. There are a few projects on github and elsewhere that can monitor JK's using different apps, etc... I cannot recomend any.

4. At the top of the app I have an entry called "Charg. Plugged: Not Plugged" (right after heating status. Does anyone know what charger it's referring to? The item doesn't change when I charge or discharge the battery.

I have not seen that in my version of the app. Note that the newest Phone Apps cover all the models and show whatever option/functions are available for the specific model it is communicating with.

 

[LMF5000]

There is no way to do that.

The BMS requires a couple of cycles to learn. But there is a glitch on the BMS stating it has 100%. Andy just put out a video (hack) on how to sort that. See here:

There is no PC App for the original JKBMS'. They use BlueTooth BLE which is very limited range. There are a few projects on github and elsewhere that can monitor JK's using different apps, etc... I cannot recomend any.

I have not seen that in my version of the app. Note that the newest Phone Apps cover all the models and show whatever option/functions are available for the specific model it is communicating with.

Thank you!

Regarding 2 - Thanks for the tip. Coincidentally I had already seen the video so I'm aware that I might need to lower OVP to hit 100%, but for now it doesn't seem to be a problem with mine (I have the default OVP at 3.6V and it declares "fully charged" and cuts the charge mosfet as soon as one cell reaches 3.6V).

My question was more about it learning true capacity over time - if for instance I set 40Ah initially but my battery actually has 45Ah, would the BMS eventually state 40Ah for battery capacity?

Regarding 4 - that still has me stumped. I can't imagine what it could mean. I can't even find a proper manual for my exact model of BMS.

Is there a way to update the firmware on the BMS?

 

[AshleyL]

There is no way to do that.

The BMS requires a couple of cycles to learn. But there is a glitch on the BMS stating it has 100%. Andy just put out a video (hack) on how to sort that. See here:

There is no PC App for the original JKBMS'. They use BlueTooth BLE which is very limited range. There are a few projects on github and elsewhere that can monitor JK's using different apps, etc... I cannot recomend any.

I have not seen that in my version of the app. Note that the newest Phone Apps cover all the models and show whatever option/functions are available for the specific model it is communicating with.

Wish the new JKBMS Inverter BMS has the 99% bug.......So, it will never trigger my Growatt to stop charging when it receives 100% status when BMS communication is used. Darn.