10S or 12S I'm so indecisive!

it really doesnt make much of a difference in your case except for the topspeed. i’d say go whit the configuration that fits the most cells in your enclosure

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WOW!! so many replies! You guys are Awesome! Sounds like the overwhelming conclusion is 12S. I definitely understand the over voltage concerns of @b264 but Enersion doesn’t seem too worried about using a 12S pack on their VESCs. This board will be my source of transportation when overlanding, but also a toy all of the time I’m not. @dareno so far all I’ve done (besides a bunch of research and shopping) is build the motor mounts from some plate aluminum. IMG_20190110_223731 I mashed up a bunch of stuff that I found here and other sites and let it evolve into something I think will work well. A bunch of you mentioned the extremely small pulley on the motor side of my build. I am using 500mm x 15 mm wide belts in attempts to increase tooth engagement and surface area on these tiny pulleys. This made my mounts really tall which I don’t really find as aesthetically pleasing as something compact, but I hope that will prevent me from needing to add a tension pulley. I have a few different pulley sizes (12, 15, and 20) that I will play if I shred these belts :tired_face: @anorak234 I’ve already noticed that these Atom wheels are less than stellar. I have one wheel where the tire mounts out of round by over 1/4 inch! hopefully, I’ll only have to swap out the tires and be able to keep the wheels. Now, not to hijack my own thread, LiPo or Li-ion? LiPo is the easy button for me since i’ll be top mounting these and they will pretty much be plug and play, but I have something drawing me to building a Li-ion even though I have none of the equipment to do so ( I guess, I just hate myself). I have read a lot of arguments back and forth about charge cycles and Li-ions being able to handle the amp draw better. All I can see for my build is that li-ions are considerably lighter. Thanks again for all of the replies!!!

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Enertion never used 12s lol all their raptors and batteries were alawys 10s

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Many people even do 13s on Focboxes, so 12s is perfectly safe imo. (I ride 12s too). As I understand it, the more cells you have in series, the less current you need to draw for the same wattage (which the ESC will convert into whatever speed you need.) Lower current per cell is always better for your battery in terms of longevity and heat. Also means you have better regenerative breaking. So, depending on your enclosure, go for the option that minimizes current drawn per battery cell. In most cases, 12s will be that configuration.

If our ESCs allowed us to go with even higher voltages, I’m sure we’d make use of it – even if we didn’t need the extra speed. :slight_smile:

Edit: For any given wattage, because each cell always has a constant voltage, irregardless of your configuration, each cell will be pushing out the same amount of current. (12s6p will be just as good for your batteries as 6s12p) So, if you don’t need the speed of 12s, then go for the configuration that allows you to fit the most cells in your board. If that ends up being the same number (12s5p or 10s6p), then go for 12s, because it will give you the option of increasing your max speed if you need it. :slight_smile:

some lipo’s are able to handle higher amp draws, but if you go for 4P with Li-ions it shouldn’t be a problem.

@rusins not sure about 13S but 12S is indeed perfectly safe and better for your batts in the long term.

It’s not a porportional relationship, higer voltage dosdent alawys mean more heat. In fact your still drawing the same wattage

I said that higher current draw will produce more heat. Taking X amount of Watts from a 12s2p battery will produce much less heat than taking them from a 2s12p battery :smiley:

Edit: wait nvm, let me think about this for a bit :thinking:

Not quit sure about that, running vesc at higher voltages also produces more heat even though drawing less amps, because your drawing the same amount of watts

12 s just has the ability to push harder because it’s not hitting the current limit of a motor compared to let’s say a 6s

Yes, you are right. In my example both configurations would have the same current draw per cell. My bad.

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Hell probably back off with the current if he goes 12s

you’re drawing the same amount of watts, but isn’t Amps the one creating heat? i believe this is the reason powerlines have insane voltage and low wattage

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  • 2000W / 37.0V = 54A @10s
  • 2000W / 44.4V = 45A @12s

This is A good example in thoery both setups should produce similar heat output although not porportional

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You guys do realize that in order to take advantage of the reduced current of the higher voltage battery for the same power, you would have to reduce the gearing?

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No, because the ESC changes output voltage going to the motors for you. :slight_smile:

Edit: But IIRC, it is more efficient if the voltage conversion is close to 1:1 / if you go at max speed. Going at max speed will increase your range, or at least I think I’ve heard that somewhere.

This shall do

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yes, i did this on my own board :slight_smile:

i’ve got 12S on 190KV motors, reduced the gearing to 1:3 which gets me a topspeed of 25Mph which is the max speed i’d like to go right now. the torque benefits of this as well!

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You mean amps?

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I’m not certain if the ESC acts like a current source or voltage source, but the ESC changes the speed for you, so all the battery does is change the max speed you could reach.

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Yeah my electrical theory is weak at best. I get how all the pieces relate in Ohms Law . I just always go back to not needing as beafy of cables to achieve the same wattage when using higher voltage versus higher amperage. Once all of that hits the ESC and flows to the motors it gets murky for me.

Not true. your still passing the same amount of energy through the cable…