11s instead of 12 or 10

I only have space, to squeeze in 11s. I have a flipsky vesc, the big one. I can find a 43.8 volt charger, that should function, at least up to 4.0 volts per cell. As 11 times 4.2 equals 46volts. Charger is lifepo4, will this work?

Also, do I get a 12s BMS, and just leave off one balance lead?

Will this be a better solution than going 10s? I have flipsky 6374 Rs. They will handle 85 amps each.

How much speed and torque diff, between 11s and 10s? Since I am so overrobust in amperage tolerance, will going 10s be fine for power, as long as I didnt want to go 35mph?

Also, should I bypass on the BMS? For more instantaneous juice?

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Probably easier to just build a 10S battery, no?

Then buy a 10S BMS, a 10S Battery Charger. KISS

We would need to know more about your drive train and battery design & cells choice…

To give some perspective, One of the fastest esk8 on the planet is running only 8S battery… @MoeStooge can give you his opinion about voltage

Bypassing the BMS is not done to improve the flow rate of electricity, it’s mostly a choice made when you cannot find/afford a BMS that can handle the current throughput that you desire for your build.

For example, say you want 100AMP max current throughput, the BMS that can handle that might be too big to fit inside your enclosure, or just too expensive… In that case, you can choose to bypass the BMS for discharge only. Then you will buy a much cheaper/smaller 20A BMS that can still do a good job balancing the cells.

My first board was 11s. Nothing wrong with 11s and a good compromise if you can’t fit 12s or use old hardware 4.12 vesc based escs and afraid to hit the erpm limit with 190-200kV motors.

I have a 11s 5A Charger up for sale in case you are interested…

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My build. Flipsky 15 inch wide trucks. Flipsky 6374 r motors. Flipsky big vesc. 6.6 etc. battery cells can be two ways. Cells are GA 3500mah, 10 amp each. I can shove five more cells in with the vesc and BMS etc. And so it will either be a 10s5p or an 11s5p. Drop skate deck, 10wide41.5long.

Sorta a La Croix. Oh, 16/66 on seven inch wheels, pneumatic. Flex batt from volokno. Segmented to fit five 18650 cells each compartment. Flex.

And so, I think IF I can squeeze another five cells into the vesc compartment, I should, as it translates to run time. While giving more torque and speed.

But really, I am asking, if you have 6374 motors, a heavy big vesc, 5p battery, 10 amp cells, Do I really NEED 11s instead of 10s, to do it justice? Or could I just run higher amps, and call it a day? I am thinking of trying to install the vesc with the heatsink exposed, and yet sealed water tight.

But really, should I be able to run higher amps with 10s no problem, and never even notice, except it will only do 40 instead of 43? I will be limiting the amps to the motor, for several reasons, mostly for safety, so would I ven notice?

How much do you weigh?

If you are over 100kg & VERY experienced riding really fast boards you might want more power…

Most builders tend to start small and build up more power & bigger boards as they progress over a few years.

I have seen plenty of folks who read about these killer boards & they build one for themselves and never fully utilize the performance & blow a big hole in their wallet doing so… It’s fucking fun though!.

Worst case scenario is you build a beast & it Reckz you on your first ride cause you tap the throttle a little bit too hard and end up in the emergency room.

  • Overcapitalization is a real problem in esk8 building lately & I don’t mean the use of uppercase letters
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Thats all fine, but could a 10s board be a beast? Could it be torquey and 28mph fast enough, and quick enough, to not wish for a 11s?

If you can go 11S, sure do it! - A bigger battery in terms of WH is always better.

But you can have a 10S board that can potentially deliver more torque at the wheels than 11S, its all relative to the overall design.

A simple design guide is; A board with the biggest possible battery, in watt-hours, with the highest possible maximum current output rating, a drive train set up to reach a max top speed that suits your skill limits, geared with the maximum possible reduction ratio, paired with a motor KV that has a max of around 8000-9000RPM at the nominal battery voltage as that is an efficient rpm range for outrunners.

Most who DIY underbuild.
My approach with electronics is not to bottleneck or hit limits. Supply road to the esc needs to over deliver. Esc needs to over deliver to the motor. Motor needs to over deliver to the load. No weak links in the chain. Heat builds resistance resistance builds heat. Heat management is the key to electricity success or failure.

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Yup, no motor covers, vesc heatsink mounted outside on batt encl.

I will say that it is generally harder to find an 11s charger because people either go for 10s or 12s

Got one, if anyone needs one. 11s charger