Got the connectors, also ordered a couple different microSD-card connectors, as the one I had earlier was quite tall, with the card sitting quite high of the PCB surface.
The bigger one on the right has a lockable latch/door, so it’s not just push-pull via friction hold. Could be better for higher vibration environment, although the microSD-card is so light it likely won’t be able to fling itself out of the connector either way.
I wasn’t impressed by the cable connectors on the other hand. They seemed to be quite the PITA regardless from the perspective of actually having a customer populating them, in comparison to a more traditional crimp-terminated cables, like the JST-XH and -PH series. Crimp-terminated connectors also have the benefit of being much more easily modifiable/fixable, as you can pull the connector out of the housing by lifting the locking tab with something small. Not sure you could do the same with these ones, as I suspect the end of the cable/wire is gonna get pretty shredded if it’s pulled out of the cable side connector, so it would like need a re-cut and re-inserting for a clean finish.
So, I looked for another solution and ended up quite near where I started originally. The JST-PH connector.
“But Simon, wasn’t the problem with the JST-PH connector that it ended too long with the 17-pin length and that it didn’t officially exist in JST’s catalogue, but only in a chinese “knock-off” version?”
Yes, but I also know in my long history of sourcing connectors that JST does have double-row versions of some of their connector series… Like the XH- and PH-series for example, these are usually named as xyD-convention (xy being the connector series, and the D indicating a double row configuration) and what do you know? The PH-series has a PHD-version of it.
I had originally disregarded it, as I assumed it would essentially double the connectors “height” (very usual in other connector series), as it’s double row instead of a single row and I didn’t want to have a very tall connector on the PCB, as it would make the BMS very bulky/tall just because of the connector, but I was wrong. Very wrong.
Turns out they’re virtually the same height (for the horizontal PCB header height, 4.8mm for the single-row PH and 5.0mm for the double-row PHD), the PHD is a little longer in the horizontal direction, but that’s fine, as I care more about the “height from PCB surface”.
so the 17-pin single-row being 32mm in length (+ends of the housing), could be just 16mm (+ends) in a 18-pin double row, which is plenty short for me and it’s officially in JST’s catalogue. Might have enough space for dedicated NTC-temperature probe connectors as well.
I’ll order a couple test connectors of the PHD and I’ll also test if the PH-crimps are compatible with it. The datasheet does have different part numbers for PH- and PHD-crimps, but I’ll test and see if they still work together.
No pressure though, take your time.
, but i don’t mind sharing my kicad files and findings for the onewheel battery. Or going off a proven open source design. I think there is an added safety benefit with this setup especially for less experienced battery builders.
