Oh man, have you even read the endless sphere thread I linked? You’ll want to set the “Designed Capacity” to the full battery pack capacity, i.e. 17000 mAh in your case. Then set the “Cycle Capacity” to what you realistically expect to get from the pack within one cycle. If the battery is new, it will be around 80% of the full => set it around 13600 mAh and it should be all good.
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Bruh I read that and I thought it meant the design capacity is the theoretical value of the cell and the cycle capacity is the actual capacity of the cell which maybe less than the specification. 
Like who the hell made this app. So confusing.
Alright, So I have tried 6 different apps - iOS, Play store, the two versions on their webpage and even the two sketch apk files that the seller sent me by email (ofc on a sandboxed device).
None connects. Some at least recognize the device but then have an error connecting.
Yes, I also tried unplugging and rebooting devices.
I wonder what’s the best course of action? Call it a failure? Repurchase?
DieBieMS and FlexiBMS are impossible to get currently, else I’d go for one.
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tried the pc app? and I think there’s a special firmware for davega that can talk to these bms?
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I actually did. However it seems it is not intended for bluetooth communication.
If I have to open up the enclosure and connect the BMS via cable every time I want to check my cell voltages, I might aswell just use a voltmeter 
I have a Davega X, but I was intending to use it for another build. 
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Dude did you get yours yet? Just got mine… this will be an exercise in dexterity and patience… holy shit this thing is fucking tiny.
Compared with standard truck bolt 
i’m gonna need a fucking monacle 
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Yeah man, I got it, thought I’d post succeses with the failures after that haha:joy:
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It’s mentioned in the initial post.
@Skaterboy58 has used it in his external charger: https://www.electric-skateboard.builders/t/external-bms-and-charging-box/79444
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Inspired by this idea, upgrading my first (only working) build. 2/5s lipos in here with a plug for balance cables and a plug for charge leads.
Continue with my balance charger but don’t have to unplug and open up Tupperware boxes anymore. Still keeping it cheap though, $4 mini paint tray enclosure
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When charging one 12s battery with two balancer chargers, do i need to split the pack into two 6s packs or can i leave them as 12s with only the balance leads split and one of the chargers pushing power into the pack? or how does that work?
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I put loop key mid pack between the lipos
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You don’t need to split it if the balance chargers are not on a common ground. You must not power them from the same DC power source, otherwise you’ll short out your battery over the common ground and you don’t want that!
If you have two independent power sources, i.e. two independent cables going into the wall socket, it should be OK.
To be safe, be sure to check with your multimeter there’s no continuity between the two ground wires of your two balance chargers.
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So what you’re saying is i can cheap out on a BMS and a 8amp charger by just buying two imax’s? holy fucking shit, imma go out and buy a 14 pin connector then.
And two imax’s
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That’s correct. It gets a bit tedious though. I have had exactly that setup with two iMaxes. Doing all the wiring anytime I needed to charge the board annoyed me. I’m much happier with a brick charger and a BMS. The price difference actually isn’t that significant.
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I’d argue it’ll be more convient since i’m properly gonna buy a 14 pin connector that’ll be able to handle roughly 5-8 amps and then it’s just plug in press 2 buttons and go. Also i don’t think i’ll be carrying the setup much around but if i do i’d still rather carry 2 imax’s then a heavy as fuck power prick, i’ll get more amps out of the imaxs too.
The iMaxes will definitely be bulkier and heavier than a brick charger with a matching power.
With brick charger you just plug one end to the wall and another to the board. It can’t be simpler than that.
With iMaxes, you’ll have two devices to plug into the wall and you’ll have many wires to plug into the board. If your battery is 12S, you’ll need a 13 pin connector for the balance leads and two 2 pin connectors for the charging wires. You don’t want to charge over balance leads. That would bias the voltage readings on some cells.
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Fair enough, i just feel like it’ll be easier with my build, cause yesterday I realised my battery pack only just fit in the top mount enclosure. lets just leave it here. Also I like general idea about balance chargers.
this is IMO the single biggest benefit of external balancing. I can often fit a whole nother P or S group by ditching the BMS. untill they get tiny like the Flexi. even that takes up some space, and often my builds have zero space left over.
I do charge through the balance leads, and there is a bit of bias but no more than a few hundreths of a volt when I checked manually. gone about 800 miles on that board and the cells still perform well and balance within .03v.
It’s not cheaper than a brick charger for the first battery, but you can have several battery configurations and charge with the same charger. I have 5s packs in a 10s board, and 6s packs in a 12s board and charge them both from the same charger (different plugs though). The 6s scooter also charges on the Imax.
I put my switches between the two halves to separate them. when separated, they can be charged on a duo charger, but if you forget, poof. so now I only ever charge one half at a time out of an abundance of caution and lack of working duo chargers
needless to say, if I build a battery for someone else’s go-go- gadget, it gets a BMS and brick charger on delivery unless they say otherwise.