FlexiBMS Lite - Flexible Configuration BMS w/ CAN-bus

I’m not aware of any related DAVEGA bug. Since the issue is intermittent, I suspect that Flexi reported incorrect values at the time they showed incorrectly on the DAVEGA. Should you see incorrect values on the DAVEGA while you’re getting correct values in the terminal at the same time please let me know.

+1

Simo’s support in this thread has been outstanding so far, definitely going to be ordering from him once he has stock again, even with the price increase. Gotta support vendors who actually care about their customers. :heart:

9 Likes

Updated the design a bit: Made the lid a bit thicker and you can now actually use the USB port lmao.

Making a balance connector for the i3-module

5 Likes

i3, like BMW i3?

1 Like

Yes, a BMW i3 battery module

3 Likes

honestly man, I think you should tell us: with all shit in the world I had to re design board, so new price for 13s-18s version is XXXX euro, I make 35% profit. Take it or leave it, thanks for understanding.

I would respect that and buy it. and many others would as well

Even if he redesigns the board to youse a difrence chip and reprogrammed the software. There’s a global chip shortage happening and he be in the same boat of missing x y and z chips.

2 Likes

@SimosMCmuffin I was just working with @WavRX on getting BMS communications working with the ILogger, everything seems to work well with the USB connected, but after it is unplugged (still connected to the pack and ILogger) we no longer get communication, am I doing something incorrectly? Thanks!

How is the Ilogger connected to the Lite? CAN-bus?

1 Like

Correct, I’ll try $38 here in a minute

Will there be any FlexiBms available for sale soon?

1 Like

Depends on the COVID chip world shortage

would love to know too. Trampa, ENNOID, FlexiBms, Nano 16s BMS all said they would drop awesome tiny bms so soon but still no one has actually done so… parts shortage is a bi_ch for real…

1 Like

In the process of resurrecting a FlexiBMSLite at the moment. In general it appears to be working, but maybe LTC chip might have sustained some damage.

Cell 1 shows voltage that is 0.006V below others, f.e. 3.640V, while other show 3.646V.

Measuring with a multimeter(UNI-T UT61E+) shows that all cells are around 3.648-3.649.

What flexi sees:

Cell 1:  3.640
Cell 2:  3.646
Cell 3:  3.645
Cell 4:  3.646
Cell 5:  3.645
Cell 6:  3.645
Cell 7:  3.645
Cell 8:  3.646
Cell 9:  3.646
Cell 10: 3.645
Cell 11: 3.646
Cell 12: 3.646

Actual measurements:

Cell 1:  3.648
Cell 2:  3.649
Cell 3:  3.648
Cell 4:  3.649
Cell 5:  3.648
Cell 6:  3.648
Cell 7:  3.648
Cell 8:  3.649
Cell 9:  3.649
Cell 10: 3.648
Cell 11: 3.649
Cell 12: 3.649

Firmware was reflashed, calibration values were entered.

What is responsible for cell voltage monitoring? Only the LTC chip or is there anything that can be shot inbetween?

@SimosMCmuffin

is it still so? I was under impression that VESC now can have integration with BMS

Not yet. it scheduled for next VESC tool relics because tramper are bringing a bms to the market. Then every one will have to reprogram to try to incorporate it in to there firmware

IIRC the total measurement error for the LTC can be several mV. There might be another issue but those measurements are still within spec for the chip.

Hmm…wait…you mentioned calibration. If the calib. values are still correct then I’m not sure what’s up.

Do you have another multimeter you can use so we can confirm the issue with the board?

2 Likes

It was a combination of both LTC and 5V regulator. Both are out of stock everywhere. RIP lil Flexi that couldn’t. :wilted_flower:

2 Likes

god dam it. this is nuts. how come all Chinese electronics still being produced and no issues… aliexpress is full of smart BMS and no one seems to care about WW shortage of anything