Wait I thought you can control cutoff and all that. Wouldn’t that prolong battery life?
Oh yes you can, but you can program cutoff from the vesc tool too. Unless it’s for charging you can set it a bit below the maximum voltage.
Oh right. From what I understand, regular bms only balance charge when the cells reach near maximum voltage. Does this smart bms actually balance charge the entire time?
At this moment I don’t know any reliable bms what wouldn’t cost a fortune. I just hope this one can do that job.
Its linked in the first post
I don’t know yet, I haven’t seen it balance my cells, as it might not need to do so yet? But I suppose you can have the cells to charge to a lower % but still get them balanced over time if you worry that they go out of balance.
It’s configurable. You set the voltage at which it should start balancing. You can also disable balancing completely.
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So who wouldn’t want to balance their cells from 0-100%?
I wonder why they even have the option of turning it off. That’s a lot of trust in your cells.
I never balance my cells at all. They don’t get significantly out of balance and I don’t charge to 100% so there’s no point in balancing. I merely keep an eye on cell voltages.
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Is it enough to place a loopkey in the B- for storage? Presumably there is a continuous current drain when the BMS is active otherwise I would not be able to connect via BT.
This screen is with the BMS with Batt set to the OFF config available with the Pro version. From what I can see it does not shut down the bms but simply turns off circuitry involved with charge/discharge.
Here’s the balancing config
Any plans for the DaveGA mod shown?
Ps. This BMS is pretty cool but so far it seems to leech quite a lot of juice. You can set it up to give notifications via the app and BT but the chances are the low voltage condition would likely be due to its use, a lithium battery can keep a storage charge for many months, this would critically drain a pack over a couple of weeks.
Pps. Don’t bother with the PC UART<->USB dongle, instead spend the money on the paid app and manage it over BT. The pc s/w is 
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Right. The question is how much the drain is. I’d just charge the cells to near-full (~4V) and let the battery sit for a couple of weeks. Then check how much the voltage has dropped and interpolate for the remaining planned storage. If it looks unsafe, you can always disconnect the BMS from the battery completely. I’m not sure what the loopkey idea is.
???
DAVEGA mod shown?
This is on the TODO list but no ETA yet. Also no plans for the LLT Power BMS at the moment.
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Thanks. The balance leads also have a B- lead, as well as a ‘main’ B- needing soldering to the pcb. My idea was to have a way to disconnect the main B- in order for the board to be stored for a few months without intervention.
On the F/W side with DaveGA I obviously thought you had made a mod to allow the DaveGA to read the cell voltages over UART with this smart bms, n/m!
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Hi guys, I was wondering that nobody mentioned the Bestech D596 80A BMS.
I think it’s the most common BMS in high end builds besides DieBieMS.
Anyway, does anybody know a passive cooled 12S12A charger, or at least 10A (AC)?
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I don’t believe that’s sufficient. This particular BMS is powered from balance leads. If you disconnect the B-, you should still be able to connect to the BMS via bluetooth. IIRC, I have done exactly that.
DAVEGA is just a display and a micro-controller (and some connectors). It’s basically a small general purpose computer! 
As such, it can do anything you program it to do. It can display the VESC data that it retrieves over UART.
It can also display BMS data that it retrieves over UART.
It could display the time left to your next birthday if you connect it to real time clock and write the code.
What I linked above is the code to make it read and display the LLT Power BMS data.
There are no plans for making the open source DAVEGA display both LLT Power BMS data and VESC data. That’s not even possible since there’s only a single UART port. Also the program wouldn’t fit into its small flash memory. I hope that’s what you have asked.
The DAVEGA X is a completely different story.
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Can you somehow get the cell voltage readings from it?
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Not sure, maybe in combination with Metr Pro?
Probably you will finde here more answers. I’m still waiting for my D596.
Manufacturer site:
http://bestechpower.com/search/?keyword=hcx-d596&submit=
Thank you sir, I get it
I’ve had the LLT Power Smart BMS on my board for the 10 months. I placed a rocker switch on the bluetooth- so that I can turn off the circuit to the bluetooth when it’s not needed. I still get a pretty large drain.
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That’s what I suspected; a constant drain on the battery.
Did you try to set ‘Batt off’ in the app(pro app only)? This turns off the charge/discharge ports.
Maybe a loopkey for the BMS B- would break the drain, as well as the black balance lead which also runs to B- could instead be routed to the same loopkey. This way the BMS is not connected to GND & ergo cannot run/drain.
Here’s some balancing with batt off
That’s 3% loss today (maybe a few low-amp burst ESC tests…ok call it 1% loss)& ok I’ve been over-balancing at too low a level and with too small a delta which is going to cause a certain amount of overall voltage losses(afaik) sending the current around constantly from pack to pack is going to cause losses. And ok this is only a 12s4p 25R
Unfortunately I don’t have the pro app. Just whatever free version that you can download online.
I really like the thought of putting a loopkey on the BMS B- as well as the black balance lead. Right now I’m going from about 70% to 40% capacity (on a 10s4p) over a period of 3-4 weeks of storage.
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I can’t think of why it can’t be incorporated into a typical anti spark key on the negative side of the battery thus providing anti spark as well as storage mode with a disabled bms
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