I have one on a 1,300wh pack that loses current faster than I would expect. I can’t say for certain that’s it’s not the cells themselves, though. Can’t we test this with a multimeter? Or some other test equipment? How would I go about testing this. I’d be happy to.
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Confirmation bias is hardly conscious.
Empirical data from collectively years of use by almost the entire DIY esk8 community. We know its not the BMS.
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What else is connected to the battery? What does the rate of discharge look like? If you are seeing cells go from 4.1v to 4.0v, there is an issue. If it is cells settling from 4.2 to 4.15v, that might be normal behavior.
A properly working llt bms will not drain a battery. It’s always possible yours isn’t working right, but it’s not the first thing I’d look at.
Searching for data to make you feel good about stupidly not using bms’s is absolutely confirmation bias.
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Nothing. It’s just sitting.
Since you speak with such surety, what part of the circuit is drawing current, and why?
Bleedresistor malfunction probably the most common, would only affect one P-group per faulty circuit tho.
Selfdischarge of cells is normally around 50uA per cell
Confirmation bias would be me blaming the BMS. I haven’t done that yet.
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I’ve had the exact same bms that is in the xlr connected to a battery for almost a year with no significant drain whatsoever.
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Do you really want to have to unplug your ESC in the winter>?
I’d rather unplug my esc than lose a 160 cell battery to undervoltage
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My Flipsky ESC’s never drained my batteries over the winter. Now I’m using Lacroix, and I have no idea how they behave.
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I loop key everything so i wouldn’t know
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It is the best option.
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Or just jank the loopkey 
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Very good, have been using stormcores since they come out without issue, same for BKB Xenith, no drain issues with that. It’s not a VESC design issue, it’s an implementation on that specific ESC. We built a board for someone in the UK and he insisted on spintend, we warned him about the issues and he replied that Ernesto recommends them so that’s what he wanted, fair enough. By the end of winter his pack was completely flat.
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I had a board with an LLT BMS and MakerX DV6Pro drain it’s self to a total pack voltage ~5V. would this mean the DV6Pro has the same drain issue as the spintend?
Not necessarily. This is one data point on an unknown build. There could be a few other things going wrong on your specific build that are causing it or it could be the BMS or the ESC. This is why data is important, identifying trends and correlations to come to conclusions.
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Don’t have to on any of my boards. Bms too
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