Using 3s Battery for 9s-11s Rated Motor

Lightweight / Folding / Portable EVs - seats optional
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alex jones   100 mW

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Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 17 2016 3:41am

It’s called "Neo C6364 KV245 OUTRUNNER BRUSHLESS MOTOR 2320W" on ebay. This motor seems to have met all of the requirements for my electric longboard, except for its voltage which it's recommended for 9s to 11s. I was just wondering if this is fine for a single motor electric longboard with two 3s 5000mah batteries wired in parallel? Thanks

nowind   100 W

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by nowind » May 17 2016 3:55am

Its uncommon to use just 3S Battery, why you wanna do this?
What ESC? What Gearing?
From my experience you should use at least 6S.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 17 2016 6:18am

Don't do that.
Otherwise you will be slow.
And to get a similar performance of "normal" voltage battery you will have to have more amps.
And amps aren't like ice-cream, you can't have too many of them without having troubles (on a eskate).
You should get a 10s battery at least, a 12s would be perfect.
That way you can future-proof your board, for example if one day you will want to go faster, you will be able to, or if you want to have a rocket you can buy hubs and you will be satisfied.

And always check the discharge rate of batteries, it is really important.

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 17 2016 7:06am

Longer run time when connected in parallel and less hassle to charge up. How easy is it to ballance charge batteries in situ that are wired in series compared to those in parallel?

I have an X-Car 120A Brushless Car ESC
15teeth to 36 teeth gearing
97mm wheels
Discahrge rate 25-35c

So would I be right in saying that you think it would be better for me to connect the two 3s 5000mah batteries up in series.
And that that would give me a quicker ride but less time.

What if I were to connect 3 of the 3s batteries up in series - that would give me 9s.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 17 2016 8:45am

9s would be ok.
with a 3s battery and your setup you are going to get a 20km/h top speed (circa).
with a 9s the top speed would be something around 60 km/h.
it's up to you to decide mate, i can't choose for ya =)

and for charging i suggest to just charge every battery individually.
so think about an eclosure that you can open easily.

increasing the voltage you increase the efficency, and the run time.

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 17 2016 10:12am

Thanks for that. I think I will go with your suggestion for 3 x 3s wired in series.
If I connect in series is there a way to balance charge 3 batteries in situ. I don't want to have to remove each battery to charge...I want to simply connect the + & - and the balance leads from the charger into ports on the side of the battery housing.

I would be using a dpdt on/off/on switch so I can charge/off/on

I've seen diagrams for balance charging two batteries in series but not for 3. I understand that when using two batteries the negative output battery would be cells 1, 2, 3 and the positive output battery would be cells 4, 5, and 6.


Image

What happens when there are 3 batteries - how would I connect the 3 x 3's balance leads into a

SCRAP THAT IDEA AS MY CHARGER ONLY CHARGES UPTO 6S!!!!!!

Thanks for all the advice - I will go with 2 x 3s batteries wired in series and make the balance leads like in the picture. So would I be right to assume that 6s would give me 40km/h?

Once again many thanks for all your advice and wisdom.

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 17 2016 10:13am

Image

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 17 2016 2:51pm

now build it

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 17 2016 2:53pm

i forgot to say just one thing, do you know that the esc you have listed can handle only 3s?

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 17 2016 7:11pm

Thanks for highlighting that arielrossolato I didn't realise that until you pointed it out.

Image

In your opinion would the X-Car Beast Series ESC 1:8 Scale 120A be suitable?
It says on the specs "Suitable Motor Type : 4 Pole sensorless and sensored brushless motor"...I'm not to sure what "4 pole" means, so do you think the Turnigy Aerodrive SK3 - 6364-245kv Brushless Outrunner Motor (or similar) would be okay to use?

Image

Just like to say I don't want to out-stay my welcome. I appreciate all the help and I'm learning from the advice given...which can only be a good thing.

thepronghorn   100 W

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by thepronghorn » May 17 2016 7:58pm

I believe that esc and motor combination should work.

Are you only running 2200mAh batteries? That is a bit on the low side for a longboard.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 18 2016 3:03am

Alex I sent u a pm,
But speaking about the esc, if you can afford it the best option is the vesc.
It has sooo many functions and parameters, and with foc
Your longboard will be really silent.
Check it out

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 18 2016 3:50am

Many thanks for the Vesc info...is this the Vesc that you mean? Is it easy to programme without a degree in I.T? (Say can a child of 5 programme it?)

Image
found at diyelectricskateboard.com

£96 inc shipping to the UK isn't too bad ...certainly seems popular and much talked about.

So to sumerise:

2 x 3s 5000mah batteries wired in series
1 x vesc
97mm wheels
180mm hanger width longboard trucks
15 and 36 teeth gearing
1 x Turnigy Aerodrive SK3 - 6364-245kv Brushless Outrunner Motor

If I do all this I should be okay yeah?
Thanks again.

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 18 2016 4:07am

Enertionboards have the Vesc for £70.40 free shipping. Cool.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 18 2016 6:44am

Well the vesc is quite easy to program, there are a lot of tutorials and guides, but don't expect it to be super easy.
I think you will spend a lot of time fine tuning it to match your preferences. (you can do that so well only with the vesc).
But don't worry you will be able to ride within minutes.

You forgot the motor mount and an enclousure.
And some loctite for the motor mount screws.

WeeChumlee   1 kW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by WeeChumlee » May 18 2016 6:59am

Hi Alex

I am not so sure that the VESC is the right choice here.
It is a great bit of kit and is highly configurable, no doubt about that.
In your case you are using a pretty powerful motor with a pretty low voltage - this means a lot of current and therefore a lot of heat.
Personally I would advice to go with a much cheaper 6S ESC, which is also pretty much plug&play, and try with that.
The FVT 120A ESC, for example, is cheap and basic.
You can always upgrade if you want but if cheap and basic works why not use it?
( I have the both FVT and VESC controllers - and various others - and find for 6S basic is good. My 2 Cents anyway.)

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 18 2016 8:40am

Yeah a car esc is enough but if he can afford it, why should he buy a basic esc and maybe upgrade later to a vesc spending a lot more.
And are we still speaking about rc car esc when we have the vesc?

WeeChumlee   1 kW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by WeeChumlee » May 18 2016 9:20am

Yes we are, why spend two to three times more for a ESC than is necessary?
The VESC is good, no doubt, but it is not the be-all and end-all of Eboard ESCs - especially for single motor builds, with a lower voltage battery, where bigger currents flow.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 18 2016 9:32am

Let's just say that with the vesc you get a smooth acceleration. No cogging. With foc it's silent.
Better deceleration, regen braking.
the ability to control your board with a smartphone.

All things you don't have on a cheap vesc.

And consider the fact that the esc is more durable and has a better warranty (well most sellers)

If you are on a really tight budget consider the car esc otherwise...

(I don't sell vescs) :lol:

WeeChumlee   1 kW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by WeeChumlee » May 18 2016 9:53am

Hi Arielrossolato

Do you have, or have you used, a car ESC? Was it so bad?
Do you use a VESC on a 6S system?

My FVT has, on my 6S system, pretty smooth acceleration and braking with practically no cogging.

I definitely do not want, and would strongly discourage, using a smart phone to control an Eboard. I know my controller has gone flying a couple of times.

More durable? Debatable.

I am not knocking the VESC (I have 3), I am just mentioning an option.
This option may not be the Mercedes - but sometimes a VW will get you there just as good.

Everyone to their own, the choice is yours to make as long as you are aware of the choices.

alex jones   100 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by alex jones » May 18 2016 6:58pm

Hi WeeChumlee, I appreciate all opinions -

I have been totally turned off with the Vesc because of the computer time involved needed to programme it. Just isn't user friendly in my opinion. When it comes to computers I don't really have a clue.

As for ther FVT 120A esc ...not able to get it in the UK - so high shipping costs - cheapest I've seen works out to around £70 inc shipping.

Going back to my first choice of 6s esc is the HobbyKing® ™ X-Car Beast Series ESC 1:8 Scale 120A which costs £38
Image

Is this pretty much the same as the FVT 120A?
The only bit I don't understand is Suitable Motor Type : 4 pole motors

Can I use X-Car Beast Series ESC 1:8 Scale 120A with a Turnigy Aerodrive SK3 - 6364-245kv Brushless Outrunner Motor?

The specs of the X-Car Beast is:
Continuous Current : 120A
Burst : 760A
Resistance : 0.0003ohms
Suitable Motor Type : 4 Pole sensorless and sensored brushless motor
Battery : 2 ~ 6S Lipoly 5~18S NiMH/NiCd
BEC Output : 6.0V ~ 8.4V adjustable/3A
Dimensions : 55x48x37mm
Weight : 145g

Once again many thanks for all of the advice and wisdom.

WeeChumlee   1 kW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by WeeChumlee » May 19 2016 3:22am

Hi Alex

Banggood sells the FVT for 35 Quid shipped.
http://www.banggood.com/search/fvt-120.html

I cannot comment on the ESC you posted as I have never used one
It does say 4 Pole and the SK3 motor has many more than that. (Don't know exactly how many but I think 14 pole)
I personally would not chance it.

arielrossolato   10 mW

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Re: Using 3s Battery for 9s-11s Rated Motor

Post by arielrossolato » May 19 2016 6:08pm

i'm not being rude, do what you want.

i've used 6s battery for 4 months, i know what i'm talking about, with the toro rc car esc (150amp) and with the vesc.

i personally think the vesc is worth the effort to set it up, it sounds complicated but it really isn't.

hope you will be riding soon :D

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