Looks great! I was just wondering: in the specs, you say 3A max charge current. Isn’t it too low to be used with regenerative breaking?
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@IDVert3X the charge current spec refers to the charging circuit (the boost converter), which is used when you plug in a power supply to charge your batteries. It can handle a much larger reverse current coming from the output (to the ESC), which happens in regenerative braking.
Thanks for your fast reply! Then it looks like a perfect solution for my next project!
Awesome! You are doing them by hand or do you have access to a hot air station at least?
Regarding the ESC, I know for a fact I’d buy into an FOC ESC with higher max current. The VESC is 80(?) amps if I’m not mistaken.
I have a hot air station, so I just reflow the parts one region at a time.
Cant wait to try out the esc. Thats what im waiting for. No DRV and 80amps constant sounds like a winner to me!
The ESC uses DirectFETs and has a pretty neat power stage layout, so I do think it will be able to handle higher current. I will post more updates/info about the ESC soon…
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Are you going to post gerbers and bom for esc for us to test the esc eventually?
The gerbers and BOM are already in the repo, but the firmware isn’t quite ready for testing yet. I will let you guys know!
ahhh ok thanks!
Super hyped for the ESC! We need something to compete with the VESC. It will make both products better in the end.
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Great work! Cant wait to see it up and running!
So for the surface mount fuses, they seem to be great for space saving but you have to solder a new set to replace a blown fuse. That sounds like a pain if you accidentally go over the current rating.
The DieBie’s two standoffs allow for Littlefuses to be used and easily replaceable. They will only increase the height by a few millimeters for a lot more functionality.
Just a suggestion. 
I did consider (very hard) to use standoff fuses, but the ones that I could find that could handle 150A were all huge and would make the PCB a lot bigger.
All the surface mount fuses in parallel should be able to handle 150A with no problem; the fuses should never blow under normal operation as the BMS should be able to protect itself before that. The fuses are intended to only be a last resort protection feature in case something like a battery short happens. It’s not designed to be regularly replaced.
Of course, I’m open to any suggestions, as I know this isn’t an ideal solution.
Oh Okay as long as it can cutoff load or the battery in time I that solves it.
@raphaelchang on the same line of the fuse conversation above. How will this BMS behave in the case of a motor or esc short ?
If I am not mistaken, the fuses are inline with the negative side of the battery terminal on the board. Shouldn’t it pop if there is a short either with the battery terminals or ESC?
The fuses are inline at the negative terminal of the battery connection, so all current coming out of the battery returns through the fuses. If the BMS software does not turn off the discharge FET fast enough (in case of ESC/motor short) the fuses will blow (after a few milliseconds at >150A). Since motor overcurrent events are usually inductive, the current won’t increase at a very fast rate, so the BMS should be able to respond in time to shutoff the load before the fuses blow.
My BMS has also died… would totally buy yours in a heart beat once you decide to sell them!