AFAIK, no build embedding a BMS has a transparent window to see any LEDS. Same for VESCs.
So, am I really the minority ?
Personnally, I see a BMS as a device that free your time/mind up by just plugging your board on a laptop-like charger and takes care about the battery for you.
Isn’t it ? (ok, that’s more sophisticated, I know)
Based on that statement, why would I check any kind of LEDs rather than the main one telling me if it’s charging, dis/charged or even faulty ?
This is just a thought, to be argued for sure.
@SimosMCmuffin : your 3 options make sense. Let see which way you’ll take.
For the 0.2 HW, the Leds are staying in, because I couldn’t test the balance circuitry, because I had the wrong footprint for the LTC6803-3, but managed to botch it on. The connections were unreliable so I didn’t trust them enough to start testing the balance and sense connections.
FlexiBMS needs to be software configured for your setup, but I would recommend also testing at least by the cell charge voltage and balancing, before burying it inside the enclosure and forgetting about it.
Yes, because I would say it doesn’t fall under the strict 1:1 clone, because they can’t directly use the files from the Github, but will have to see if even I will remove them with further development.
Side topic, but today I got my first ever self-designed fully assembled PCBs that I designed in work for a customer! The boards were all designed by me, with couple feedback iterations between designs with the customer. I also sourced all the components to fit the customer’s specifications. (Customer info has been removed for NDA purposes and I probably can’t tell what the specific application of this board is).
Slow progress last week, was working overtime on most days and bought Far Cry 5 and needed to finish before I could focus on anything else properly .Got a lot done on Sunday and today.
Everything is electrically connected on the board, but I need to go through and improve trace widths where needed. Wire pads need to be placed and I’m gonna try to do some separation between the high current and low current grounds for improved noise performance.
Boards were ordered last weekend, I’ll have them next week. Github repo has been updated with the 0.2 files ( https://github.com/SimosMCmuffin/FlexiBMS_hardware ), BOM still needs a review and I’ll order the components.
Things are slowly progressing and I’ll update again after I get the new board assembled.
Oh I missed the last update. Nice !
I would have suggested (but too late) to extend the PCB somehow under the JST connector to avoid too much stress in solder joint when plugging/unplugging balance plug.
Is it a real concern or not ?
Can’t wait to see the assembled boards ! Keep the good work !
It’s a 13 pin and through hole component, if the solder job is done properly it’ll be very sturdy connector and won’t care about little mechanical stress. I’d be more worried about the balance wires getting pulled out of their crimps.
The current consumption is very dependent on the power and run mode. I would refer at this point to the STM32L433XX spec manual which has a TON of different current consumption specs for the different running modes at different operating conditions as shown below.
Yeah I read datasheets, was just curious how they act in the field
Just to give more context I am building my battery as 15 x 12S1P groups each of them will have PCB on top with LTC6803 (cheap good balancer IC) + STM32L443 (STM32L0 eats more current than L4) also 6 temp sensors and 1 x AD8418 bidrectional current sensor All of them will be running as I2C slave and communicate to main MCU
I want to keep track of all my 18650 cells and keep them in good balance I will also try to apply all those scientific methods for biggest cycle ratio and capacity
.Got a lot done on Sunday and today.
Do you have maybe some measurements on current consumption?
