Archived: the OG noob question thread! šŸ˜€

@DEEIF I was told between 36-38.4 for a good lifespan. I set mine at 37v

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Li-ion cylindrical cells can go pretty low - most manufacturer datasheets spec them down to 2.5v, and most people on here go down to about 3.3-3.0 +/-. I think I had mine set with LVC starting at 3.2v/cell and ending around 2.9v/cell.

It really depends - itā€™s a tradeoff between how much range you want, and how much cycle life youā€™re willing to sacrifice - discharging lower (below 3.0) is harder on the cells, but gives you somewhat more usable energy.

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Thanks @flasher and @MysticalDork! My cutoff should fine then at 37V :smiley:

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Wow thatā€™s high. I have mine set at 3.0 for soft and 2.9 for hard cut off. I needed more range for Bergā€™s. I didnā€™t wanna upgrade battery just yet. It still has plenty of life in them.

@pookybear 37 is just 3.08 per cell. My build uses a 12s6p 30q. Range isnā€™t a factor for this pack as I intend to double it in the future. So I decided to give the best life cycle I could without sacrificing much range in exchange. Iā€™m making sure it lives at its maximum possible :slightly_smiling_face:

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That makes sense. I have my Vesc set to 36v. I read that wrong. I thought you typed 3.7v. My bad.

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The size is this.

I usually set my cutoff start at 3.4V/cell and my cutoff end at 3.1V/cell

So for 12S thatā€™s 40.8V, 37.2V

But there is no hard and fast rule as @MysticalDork mentioned

Well the only hard and fast rule is cutoff end needs to be 2.5V or higher and preferably not even close to 2.5V

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Anyway I can swoon @Dareno to help me build my first build?

ā€¦with compensation of course :))

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Yup thatā€™s the settings VESC tool recommended to use!

Interesting. Iā€™ve been using older versions (Ackmaniac) and I donā€™t recall those being the defaults. Maybe they changed it LoLz

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Iā€™m not sure on if I set up on ack or trampa VESC toolā€¦ whichever one @torqueboards made the guide for :joy:

Best sub 150e hubs? Meepo nls?

Is there a way to make my drivetrain more efficient given that the hub motors I use are limited to 350w?

  • Currently I have it set to PPM BLDC, with 12a battery max per vesc, 10s2p 30q battery and ownboard hubs

  • My motors and hanger are never hot unless I ride for the entirety of my battery pack (12 mi)

Would using watt control and limiting it to 350w per motor create a more efficient result?

I donā€™t really know how to calculate this, so any advice is good :slight_smile:

In general, lower power is more efficient, as is lower speed (less wind resistance). Thereā€™s honestly not much more you can really do to improve the efficiency using only software other than going slower and limiting your maximum power output. Youā€™re not that far over your 350w rating already with your 12A battery max.

Basically if you want more range, either go really slow, or get a bigger battery.

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I figured that was the case, lol.

I found some calculator online that says 8.33a should be my target amps at 42v and 350w, but that seems like it wonā€™t be worth it.

I know itā€™s a semi loaded question, but would you personally prefer a 11s 3p pack of Samsung 30ts or a 11s4p pack of 30qs for a boosted board clone ( just changing battery and vescs). The 5v sag I get with the 24a load on my 10s2p battery for Spuderoo is just depressing, and Iā€™m looking to eliminate* that while still pushing 20a per vesc on my boosted project

* Make it less noticable at leastā€¦

5v of sag at 24A (12 per cell) seems excessive for a 30Q pack. Based on the internal resistance of the cell, Iā€™d only expect a sag of 1.5 to 2.5v at that current, and a maximum of ~4-4.5v at the full 40A that pack should be capable of.

Honestly battery selection is all about space and how much range you want - calculate the energy of your packs by multiplying the capacity by the nominal voltage and see for yourself.

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https://www.thingiverse.com/thing:2981889 Should I get this, like how much could this improve cable cleanness from a scale from 1 to 10? Or trying to 3d print this wonā€™t help because itā€™s just so fragile?

Careful or you will call the humdinger and feel his wrath

Thingiverse is so broken, itā€™s down right now completely looks like https://www.isitdownrightnow.com/thingiverse.com.html

In general 3d print with the right material can be durable but donā€™t expect PLA to act like TPU or Nylon.

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