@janpom do you have a build thread for your external bms charger?
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No, sorry. I might be able to dig out the schema. It’s overcomplicated though. Today I would prefer the FlexiBMS over external charger any day. It takes less space in your enclosure than a bulky waterproof connector for balance leads. And charging is zillion times easier, especially when you’re on the go.
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Still waiting to get my hands on a flexi.
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Dose any one know if the llt have a charge cut off?
DieBieMS
FlexiBMSLite
@Battery_Mooch was asking but Im struggling to fined out if the llt dose as well
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What Smart BMS is this?
In the end which connector did you end up going with in the photo, im considering buying 3, but damn they are pricy
The LTT indeed Does. Only thing im still trying to figure out about the LTT is how it does it’s Bleed Balencing. prehaps my version is different ive been told the cicutry does not allow for Active Balencing (which seems true)
But it does… Bleed the cells into other cells while just bleeding cells. so packs 1 3 5 7 10 or 2 4 6 8 will play around with eachtoher. (confirming this is without a charger)
But the Flexi stright up Active Balences… Would love to somehow wire a flexi, with a Diebie… So my passive power (solar) can be neatly tickled into the cells or something.
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Everything you need is right here… props to @rosco for the links.
Expensive, but by far the best solution i’ve found. And these ones are pre wired 
i like to run the wires from the port to a male jst and put the female jst on the battery.
Egg 1B 12mm balance -
Male plug link
NZ$ 15.27 37％ Off | FGG 0B 1B 2 3 4 5 6 7 8 9 10 14 16 Pin Male Plug Connector Welding Cable for Camera Power Flying Leads Cable
Dust cap link
NZ$ 12.66 | M12 Connector 0B 1B 2B Series BFG Plug Caps BRE Dust Cap for fixed sockets HGG EGG ECG EEG Plug and socket connector
https://a.aliexpress.com/_mKi1g7L
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Belive these are much larger than the ones you had in the photo right? im looking for that tiny monicole sized 12-16pin 
It’s for a compact shorter build intergrated. so it’s really only just got space.
These are pretty much the smallest you will find dude. 12mm diameter hole.
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that’s an xt30 next to it for size reference. Its tiny.
Its worth the money, especially buying the prewired one. Its the nicest plug and socket I own by a long shot.
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I’ve made this case to hold the LTT BMS and use it externally. Needs a couple of M3 bolts to hold it together.
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Nice one dude! Great, simple solution
Hey, I’ve been using the ltt smart BMS for a 10s since May and have had only a few issues. When I first started using it the 10th cell would drain and charge much faster than the other cells but this has since stopped. Instead now the 1st cell is doing the same. Is this issue likely to do with the BMS or the battery pack itself and how would I go about resolving this?
why don’t you test those individual cell pack individually ?
I’m quite the fan of this LLT smart BMS for my lipos.
For a while I was wondering how to enable the balance while not charging thing and finally figured out that it’s by turning off the balance while charging function. So when I charge I can flip the balance while charging on, and otherwise turn it off and it just constantly bit by bit keeps my battery balanced. Fantastic.
Towards full charge my 28Ah lipos sit around 0.04-0.05v off balance across the pack, and it takes about a day and they are back to 0.015v in balance.
Any benefit to turning the accuracy up to like 0.008 or 0.005v? I guess it would just balance more but I think a 0.015v range is acceptable so it’s not like most of my cells are trying to discharge all the time, what do you guys set your accuracy to?
I’ve never had any pack set to tighter than 0.03V balance voltage range (between highest/lowest voltage cell) and often use 0.05V. Occasionally 0.1V.
Balancing to 0.008V or 0.005V just means a ton more time spent balancing for almost zero difference made once the cells start discharging down. It really extends charge time too.
Voltage differences this low can actually be smaller than the voltages caused by electrical interference present in every wire. Unless the BMS is designed to take this into account this can result in a different voltage reading being read every time a measurement is taken. This results in the balancing constantly switching on/off or even never stopping.
IMO, in a high electrical noise environment like esk8 you want a higher voltage difference setting.
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if my cells are not within .0001 I just feel a disturbance in the force and cannot ride right.
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I just don’t balance at all. I merely keep an eye on the cell voltages. Then if things get seriously out of balance (which is rare) I sort it out manually.
0.015V difference would keep me calm. Definitely no need to set the balancing accuracy higher unless you really really need to charge to 100%.
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I have a non-typical setup with 12S LLT BMS used for charging only, like in picture below, b0 and b12 balance wires are wired to thick charge wires (this is to reduce the number of balance wires coming from external BMS to skateboard).
So when I charge it, Android app (v3.1) shows higher voltage on first and last cells (+0.1 or +0.2 V) compared to non-charging state (all batteries are pretty much equal in non-charging state).
When charging goes above 4.1V, it constantly turns off and on as overcharging happens on first or last cell.
My first thought is it’s because of resistance difference of balance wires - balance wires b0 and b12 are of much lower resistance and voltage measurement is done wrong on them.
Am I right? So I need just to add some resistors between b0/b12 pins and thick wires?
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