Can I ask about the max recommended charge current of 8A? Molicel specs the cells cycle life at 4.2A each and allows for fast charging to 8.4A each, is it the BMS limiting charge or am I misinformed about safely charging p42A
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Mooch said this once.
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This is simply a recommendation. A 12s4p at 8amps would charge in under 2 hrs I don’t see a need to charge any faster, the slower you charge the longer your cells will last. Also the fuse I use on the charge port is limited to 10 amps
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That’s for single cells in open air.
A pack has all the cells heating each other up.
A wrapped up pack (tape, fishpaper) traps in more heat.
An esk8 enclosure prevents cooling of the pack.
Depending on the setup you could easily be hitting the 45°C limit for 8.4A charging. 4.2A charging must be below 60°C (for the hottest cell in the pack). These are the max charging rates for those temps. “Standard” charge rates, that don’t zap cycle life, are lower at those temps.
With cells that stay at room temp you could go to 4.2A and not badly affect cycle life (all charging and use affects it some) but cells in a pack will heat up so IMO 4.2A should be considered a cycle-life-shortening fast charge rate. I recommend staying below 4.2A, perhaps around 2A/cell.
Each of us can set out own limits though, based on our priorities and preferences for safety, cycle life, and convenience.
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Ah yes thanks, should have caught that but I had it in my head that cell manufacturers’ charge rates for stated cycle life would be quite conservative to maximize cycle life. Similar to the 0.2C discharge rate, as opposed to being a bit ambitious and somewhat conditional, so that the charge rates can be used as a marketing spec in their own right. I guess everything to do with electrochemical death contraptions is conditional. Enlightening as always
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The charge rate used for setting the cycle life spec is indeed 4.2A but at an ambient temp of 23°C. Once the ambient temp goes up, like when cells are in a wrapped-up pack, then the cell is getting hotter than it would when tested as a single cell out in the open. I don’t know how much this affects the cycle life though. Molicel would say to test the cells to quantify the effect of this higher ambient temp as there are so many variables,
Molicel is great because they also go an extra step and spec out a max charge rate and the max temps for the standard rate (60°C) and max rate (45°C).
It’s all a bit confusing to me though because some cycle life and charge/discharge ratings/specs can seem to be in conflict for some cells and we don’t know if it’s a datasheet error or if there is something we don’t understand.
We can only make rough decisions about how hard to run cells, understanding that increasing charge or discharge rates by any amount will affect cycle life. The harder we use a cell, the lower the cycle life. We will never be able to quantify how much the cycle life is actually affected unless we set up some testing. Understandable, but frustrating.
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I will be doing this too now 
now to make my way into that Lacroix FB group 
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This is fine for most of us, the closest I get is charging my 20s4p at 10A (800W+!!). I don’t see many trying to charge any faster (per cell) than that really.
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New modors!
Free shipping untill I can figure out how to add it to this product on shoppify! 
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3 drive trains 3 complete High performance esk8s coming up! I am in love with this gun metal anodize 
@3DServisas 
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Broooo gun metal looks so good. That might be the move when I order my finality. Still debating between that and black, but now I’m leaning toward this!
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It’s super clean, I think for sure the way to go. Like it very much!
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What gear ratio is the 5" drivetrain?
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2.6
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Boy how you get all these high paying clients that want Hoyt tires and 3DS stuff lmao
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Why do you say this? What is the benchmark for value here? Also, these particular new Nano gear drives are actually very cheap 
They will be coming very soon, the set I have here is for testing.
The reason I prefer to use @3DServisas gear drives is very simple … they work very well and they work for a long time…they also sound really really good. I find other drive trains I’ve used to sound a little bit like a toy, and that puts me off like a lot. When you are spending 2-4K on a PEV I don’t want it to sound like a toy or break down. So if I take on a custom build I prefer to only use parts that I have personally tested at length and parts I can say with confidence will last. Also…3Ds parts are very competitively prices - not sure what all the misconception about them being expensive is.
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have you seen his work? 
of course if people want the best they will go to SKP
not totally dick riding, but he is legitimately very honest, patient, dependable and turns out the highest quality work and that makes him my go to guy for anything i don’t want to do or can’t do myself
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