That would be a great feature. But a discharge mode requires a load (like a resistor) and need some hardware changes and heatsinks I guess.
It may need just a small heat sink, because the same balancing load can be use for this purpose.
Even a small load will produce great benefits, because the strategy is for the ions to move to prevent metal plating inside the cell, it’s not meant to be a fast process but ratter a continuous one that will stop at storage voltage.
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@atKa Normally the prototypes I make are 95% ready for production. I only need to fix small bugs + BOM list. So when I think everything is ready (I verified that all the desired functionality is possible) the step to production is small.
@Pantologist I assembled these two with paste + stencil followed by a reflow oven indeed. Really simple but the result is awesome. Pricing is not bad indeed.
@longhairedboy You fall in love way to easy, what I showed so far is BORING, the awesome stuff is coming upcoming weeks (I hope).
@Pimousse
Indeed trough CAN. As far as I can see the VESC does broadcasts, the BMS can do the same. The master VESC or any other master on the CAN bus can use all available information to do awesome stuff. Let met do the awesome stuff first, ill start the awesome stuff later 
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@Kaly Nice thought! For this however the BMS would need a mechanism to turn itself on, currently the uC (and all other stuff) is disabled when the BMS is off (to prevent battery drainage when the battery is stored for a couple of months). For this to work I need to add a system that periodically enables the system. Ill look into this, this periodically enabling the system would allow a lot more than bring the battery to storage level.
@All The BMS has balance resistors that are designed to drain the battery. It would take several days (depending on the battery capacity) to bring the cell voltages to their nominal voltage but since we can assume the battery isn’t going to be used for several days this is no problem.
(My apologies for the bad writing, I am on a train and not focused, ill correct it later).
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i’m a sagitarius. everything is glorious or terrible; emotions run high.
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Awesome news ! 
Can’t wait !
excuse off topic but, as much it feels home, this is engineering topic on the internet and you just used zodiac
take no offense, somebody had to do it and i’m gemini 
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Ok lots of progress:
Me and my brother now both have a BMS mounted to (me) or insite (my brother @MrEpiquad ) our longboard and are testing it in our everyday commutes.
Small video of the charging / on / off modes. I even implemented an extremely simple state of charge indicator based solely based on 100%*(consumed Ah)/(battery capacity Ah):
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It’s working like a charm so far ! No more usage of dangerous cheap chargers from hobbyking.
And it came pretty well together along with the vesc in one enclosure.
I din’t put the bms in the battery enclosure since I want to make the battery modular but with out having to put a bms in each battery pack.
Here is the bms mounted on a aluminium plate next to the two VESC.
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Love to see that !! How far is the development ? Is the software and hardware ready or do you have still features to add ?
The Bokma brothers rock!
Can’t wait to see more!
Man, I just want to start buying the components now.
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Holy, shit, i just came across this thread, and this great build.
Respect, i guess thats what may of us are waiting for, at least spoken for me.
Will you announce it here if some “prototypes” are up for grabs ? Or actually does the BMS allready work as it should without major-changes needed?
One thing that would be nice for me for future developement on the BMS would be that the PCB either gets the Dimensions of the old (4…) or new (5,…6,…) VESC. That would make it easier to fit and arrange them nicely on (my) board.
thanks for that work
Notger
@Nordle My Teensyduino-project is uploaded here is the link https://github.com/RunningPenguin/TeensyWay
@JTAG very nice project glad to see it working. I need one for my self balancing scooter which I build lately. It uses two VESCs and an teensyduino. To get the control software to work I used lead acid batterys but in the future I would update to LiPo or LiFe and need a BMS for that and yours looks really good. I would be very exited to hear from you.
Regards
@JTAG Maybe you want to update your first post? How is your project going? Could you implement a feature to level the cells only when the drift is more than 0.5V?
Sorry for the lack of updates, I had lots of other projects.
The BMSes are working nicely on our esk8’s I did update/added a few things:
- Added SD card holder for logging / debugging -> mainly to develop / evaluate SoC algorithm.
- Added an extra shunt to allow for higher discharge currents -> for future use in EV / solar boat.
- Added a safety shut off -> If the LTC looses its configuration due to a uC brownout or misbehavior the LTC automatically shuts off the power stage.
I will be sending this design to the fab this week, should be in before xmas 
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Very Nice indeed…
Looks really nice to me.
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