I have a 40Ah pack and bypassed discharge and set max discharge current to 70A with my Focbox Unity.
Most off the time the postive. But it is not that most important.
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It is not safe. When some cell groups reach 4.2V and others not, BMS will stop current from the charger and will balance cells. When you charge through bypass BMS can not stop it.
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This thread is the top result for “bypass BMS” yet has no diagrams to link to
fail
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Discharge bms can suck my dick.
Second bad stack as a result of a discharge bms just shitting itself for no reason. Anyone know what the bms is in the bioboards thorium? Its a big red thing.
#fuckdischargebms
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Running your discharge through the BMS definitely adds an additional failure vector for the drive train.
When the choice is presented between higher risk to body or higher risk to battery, I’ll choose battery every time. Those are just money.
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Same here, I know I can afford a new eskate even if the ones I have get incinerated and there is nothing to salvage, but I don’t know if I can afford getting hospitalized for a bad crash. I’d like a slow burn fuse with a 100% margin of tolerance but definitely no discharge BMS
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Yes it looks very much like that
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Interesting read,I’ve only ever built a pack for charge only and bypassed discharge bms and my second one was an enertion 10s3p which was bypassed,this will be my first build using one that was made for charge/discharge,at least it has a smart bms and app so I can keep an eye on cell v when pushing it to the limits!
Jut noticed this bms. Its the neptune one with Vesc compatibility but the prices are ridiculous.
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A distinct feature of Neptune is to allow user instantly between from off-road to on-road biking with a quick switch without their smartphone.
What does that mean? Increase/decrease discharge current limits?
…and is the VESC compatibility just a matter of it displaying VESC telemetry or is it more involved than that?
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A friend will have DieBieMS produced.
He is geting right now a quote for 50, 100 and 250 units.
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No, don’t do that. If the fuse blows you can’t brake anymore. Fuse the charge port, but let the pack die if that means you can still safely stop.
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No. Fuse the charge port only.
I personally would rather the fireball under me still have brakes so I can stop and get off of it and not get run over by a car… …in the event of worst-case scenario.
If you value the skate hardware more than your body, then fuse the discharge… 
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Second bypassing BMS for same reason , and just charge only, if your battery is made well and new cells should be fine.
I have no BMS and im still alive.
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