Postman arrived. the components are amazingly well lined up pick and place me nine has done grate job
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Got mine as well, Thanks!
XT30 vs XT60
XT30 rated for 15A continues Flexi BMS rated for a 8A charge Current down side is XT30 only take a AWG18 cable 0.82mm2 and my fuse holders have bigger cable.
With the XT double the width I’m thinking little tails are my best bet
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I have 100% soldered 16awg to xt 30
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Don’t talk to me or my son ever again.
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That escalated quickly 
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Would it be possible to run multiple of these in series for a 20s pack?
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You won’t be able to use CAN-communication, but it could be done if you only use them to independently charge them as two series 10S packs. You can’t connect the single charger to both packs at the same time though, so you’ll either need to charge them one-at-a-time or use two floating output chargers to charge both packs at the same time. AKA, charging wise, handle them as two independent packs.
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Nope, don’t know where that 8A rating has come from, maybe some older HW version, but current HW from 0.4 forward officially supports up to 10 Amps charging current.
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Thanks, will test soon dual chargers in parallel and didn’t want to fry anything
Thanks, i had to do a quick read on floating outputs, and that actually taught me a bunch 
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I was hoping for the nice can-bus and single charger solution.
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Unfortunately, no.
FlexiBMS Lite doesn’t support series daisy-chaining.
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Then it sounds like there is customer demand for a higher cell count FlexiBMS. I’buy one. Or three 
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Wow I didn’t know how little it was, nice work
is it just a matter of the not (yet) isolated CAN-Bus?
Or are there other things?
Because otherwise you could just swap the CAN-IC to an isolated one and daisy-chain them on the CAN, but in general still treating them as own packs.
Yes sorry was from back when you were having heat issues with mosfets Over 7 amps before you swoped them my mistake
Yes, there is also the matter of the charging current path control, which uses 60V FETs. AKA, they gon’ /might blow if subjected to a higher voltage then 60 volts (>~14S). Daisy-chaining capability means, that it doesn’t make as much sense to have charge path control on every unit, as it will either need to be over-engineered to be able to handle the possibly higher voltages at the cost of charging current.
AKA, for example, if the FlexiBMS Lite supported daisy-chaining 2 units for a 24S setup, then that means that the charge path control would need to be able to always handle up to that full 24S Voltage (~100V, so 120V FETs) instead of 12S Voltage FETs. This would mean probably bigger and more expensive FETs on every unit, even if you don’t use it in a daisy-chained configuration.
Now it makes more sense to make a distributed system if you were to design a true daisy-chainable BMS that can support essentially up to whatever S-packs (100S+). In a standalone BMS, like the Lite, everything needed to use the system is in an all-in-one unit and doesn’t need anything else (small, cheaper, simpler). A distributed system starts to look more like car EV setups, where you have MASTER BMS controller, which is then connected to SLAVE units, then there is also a charging path control, which can then be made to fit the required system, from low voltage, low amperage (<100V, <25A, solid state technology) to EV car use scale (>400V, >400A, mechanical contactors).
I have already done a concept design and a prototype for a true distributed system some time ago, but the customer at the time backed away and I lost interest in furthering the development, as I didn’t have any personal need for system like it, so I then focused on designing the Lite.
IMO, if you’re operating in the <100V voltage range, it makes more sense to use standalone BMS’ as the physical pack size is still or might be somewhat on the smaller size, but that’s me.
It’s a compromise at the end of the day, and I lean on the standalone solution for the aforementioned reasons.
EDIT: also, all 25 units have been sold and shipped to their respective buyers, so thank you guys for that!
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