I’m confused - you say you’re aiming for 200a continuous battery discharge and yet you’re using a discharge BMS that limits that to 70a?
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Yes, we are building the battery for theoretically 200A continuous.
During our tests we stresstest different BMS and had no issues so far with them. We will continue to test with even higher voltage and more current to get sure that ever part we are using is 100% bullet proof with our setup.
Only the fuse is limited to 70A (if they have such fuse). The Diebiems can handle up to 140A if I’m not wrong…
Couldn’t find that motor on HGLRC. I’ll ask, the suppliers, if not every 80100 have bearings.
The Fuse is 80A on both BMSs we are testing (DieBie and Bestech D596) If the fuse don’t blow of everything it’s fine.
Uff feels like playing with fire then…
(Ich würde die Sicherung tauschen 
)
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We are testing this BMS for years now. never had any problems with it. If we will experience some kind of trouble or limitation from the BMS we will find another solution. But as soon as everything works flawless, we don’t see any reason for changing the BMS. Yet, we are working already on improvements.
wait, you’re running 200a on a 80a fuse?
- the BMS is probably limiting to <80a
- the fuse is broken?
- the fuse is over rated and isn’t a safe 80a fuse if it doesn’t blow when its suppose to…
(unlikely)
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I agree, feels really risky… Have you measured the current you’re putting through the system at all? Using 200a stuff on a system fused at 80a seems like a one way ticket to blowing the fuse…
EDIT:
I feel like this is probably what’s happening… Gonna impact performance if it is. 80a isn’t really enough for this build I think 
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Thanks for the suggestion. I think you have a point. We need to keep in mind, that we are still in the R&D period. Until the final version is done, there will be some changes and improvements. But we are always open to new suggestions. So what BMS you guys think we should use instead of DieBie or Bestech?
bypass discharge with a 210a fuse
The VESC’s should only draw 200a max in normal conditions.
If something abnormal happens (short, bad settings, etc) the fuse will kick in and protect it
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I would say either would be fine, just use one without a discharge port or just bypass the discharge…
BTW, I know you’ve already started with your batteries, but have you considered checking out LiPo packs?
How likely is that this will damage the BMS in worst case szenario?
Shouldn’t affect the BMS at all - this is what pretty much everyone does when using BMS’s AFAIK
Yes, but we can’t go LiPo for a consumer product.
First it’s more dangerous, second you will experience more sag, third the lifespan of LiPo is worse compared to LiIon.
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Know I got you. But than you would run unbalanced, which should be finde, but we want to integrate Metr Pro and run balanced, if possible and get all the data. But yes, it’s an option.
The BMS can still balance the cells if you bypass the discharge port, as long as all the balance leads are still connected. The only thing that bypassing discharge does is remove the BMS’s discharge limit and ignore any output switching that the BMS provides.
That’s fair - I just figured the decreased weight and higher discharge rates would be attractive for your build.
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Thanks, we’ll keep it in mind 
We did some research to figure out where the limitations of the MOSFETs used in the DieBieMS are and we found out the there are 2 parallel HEXFET POWER MOSFETs which each is capable of 240A @60V. That means the total current can be 480A continuous. The used fuse will not blow until a continuous very high current.
Short peaks over 200A are no problem. I see in real world application no way to blow off the BMS. But we will stress test every single part even more in the next weeks and make our own experiences, to assure that everything will work under every condition and circumstances imaginable. I hope this reassure you.
Source: https://www.infineon.com/dgdl/irfs7530-7ppbf.pdf?fileId=5546d462533600a40153563a9d1e21d8
New fancy stuff for testing. We are really curious about what trucks will gonna make it to our production series. Big shout out to @Psychotiller and @klaus79856 thanks for supporting our project!
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