Yep that’s what I seen in my use. I charge most of my ESk8 at just over 6A and that is more todo with the size of chargers. I would be interested knowing if the quality (by this I mean the less noise ones like mean well HLG range) of the bulk charger. @SimosMCmuffin looked in to them a bit in this thread and said that we’re good in how low noise thay had. I don’t know how that effects the life of the cells in the batery.
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The noise is extremely high frequency and very low voltage compared to the charging voltage. I don’t think the battery even knows it is there.
A very (electrically) noisy charger could potentially cause problems with a BMS or some other electronics though, causing it to malfunction or lock up. This would take a lot of noise/interference though and I think we would have seen hints of this happening if it was a real issue with some chargers.
The interference could affect balancing accuracy more easily though. No good way to predict that or easy way to fight it. Just use a decent charger. 
I was measuring the noise in the current waveform for the MeanWell led drivers. I had found a couple of research papers that found that there was increased degradation in the cell cycle life, when there was high amplitude + high frequency ripple in the charging current.
I do believe the paper I was referencing back then was this:
There are couple relevant graphs that demonstrate their findings. Basically, cycle life degraded faster with the higher frequency AC charging current, power delivery capability decreased faster and cell ran hotter indicating higher internal resistance.
Now as I was looking for this research article I also came across this newer research article:
https://www.researchgate.net/publication/330803958_Aging_effects_of_AC_harmonics_on_lithium-ion_cells
Which found and concluded that AC harmonics have no effect on cell degradation and cycle life, so now I don’t exactly know which one is more relevant to our use case. That being mentioned, they didn’t go to such high AC ripple frequencies as on the first article.
So maybe cell manufacturing and technology has gotten better over the few years, or maybe they didn’t go into high enough ripple current frequencies like the first article did, and therefore concluded that the lower frequency AC ripples have less effect on cell degradation? although the first article did find degradation even at the low ripple frequencies…
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Thanks for the links!
That first paper subjects the cells to huge levels of AC ripple current. It seems to make sense that current like that would degrade the cycle life of a cell as it’s essentially being charged/discharged by the AC current. The results could also be unique to those specific cells (construction, chemistry, etc.) and only for levels that huge.
IMO, the AC ripple current levels present in the power supplies and chargers used by the esk8 community are tiny compared to the levels used in that first paper.
Just guessing based on the ripple/noise level specs for these supplies though.
It would be interesting seeing a good cycle life comparison of a few cells using a good “quiet” charger and some piece of junk with lots of noise/ripple on its output.
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Box looks like the delivery guy used it as a seat cushion 
The bms still looks good though, never realized how small it actually is.
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Hello I’m new here and I just finished my first electric longboard.
I charge the 6S LiPo battery with a balance charger and this project is great to switch to a standard charger! So I’d like to buy the FlexiBMS Lite and the Metr Pro (or Metr Pro CAN?).
I’m running a Flipsky Mini Vesc 4.20 (based on 4.12 hw) and a 6S 4Ah LiPo battery. Can someone show me how to wire all the devices together? VESC + FlexiBMS Lite + Metr Pro.
Do I have to opt for Metr Pro CAN?
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I can almost make out the ass cheeks pressed against it.
But… wow. That is squished
Welcome and 'gratulations on the build.
Yes.
Are you planning on using some kind of e-switch between the pack and VESC or do you just un-plug the battery from the ESC when not riding?
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Thank you so much!
I’m already using an anti-spark switch between the battery and the VESC as you can see in the picture: https://i.imgur.com/Xm0CBZb.jpg
atm there isn’t a loop-key to physically open the circuit but I’m considering to install it (in addition to the anti-spark switch) in order to cut the electronics absorption even when the switch is turned off.
Another question: Can I solder a 6S JST balance connector in the pcb or it needs a full 12S connector and adapt it for my battery’s JST cable?
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If you have a male header (PCB-side connector) for the 6S battery (7-pins) then you can use that.
The connector doesn’t need to be fully populated, if you’re using less than 12S pack.
You can follow this wiring guide
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Basically my reasoning for most things I do with my PEVs. 
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Great, thanks!
For the first setup, can I write/read settings within the Metr Pro app or I have to connect it via PC for set mandatory parameters?
Does flexi have the ability to limit charge current?
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I think you might need to reverse the rx Tx pins on the metro pro cable as I got a feeling the flipsky VESC 4 is one of the VESC that have them reversed.
The RX / TX pin are swapped in the Flipsky VESC schematic compared to the VESC shown in the Metr Pro setup guide. Do I need to wire like this: RX-RX and TX-TX ? In some applications it needs to be reversed if I’m not wrong.
You can set a limit where it stops charge. But you can’t use a 10A charger and set 5A etc on bms and charge with 5A only
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Doesn’t matter, Metr Pro autodetects RX and TX, even if they are swapped.
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Great, thanks!
Thanks dude, that was exactly the info i needed. Just gotta hope now i can adjust the current a little with the charger itself. Don’t particularly want to be chatging at the full 10a.
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