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Discussion Starter #1
Ok, doing a small project for a quad for my son, and i was considering the below setup to drive it, but my lack of knowledge on batteries is really holding me back. I know i need at last 4 @ 12v batteries to make the 48v, but what types and where to get them is becoming the tough point. Can someone provide me a recommendation as to the place to buy them and the types that would be ideal? or even if the kit i noted below should be bypassed for something else.

Thanks

https://www.amazon.com/gp/product/B0785MXPHM/ref=ox_sc_act_title_1?smid=A2RB21RUGRFV4T&psc=1
 

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Howdy,

It depends

...on the area you have to put the (4) batteries into

...how much weight the vehicle can carry (safely)

...& how long you plan on him riding at a time

IMHO smaller is better


Remember

...the more weight you add

...the harder the motor has to work


I have used (4) 12V 12AH SLA (sealed lead acid) batteries like these on many go karts

https://www.amazon.com/ExpertPower-...id=1517327360&sr=8-3&keywords=12v+sla+battery



on my !Arriba! kart (48V 1,800W motor)

...the (4) 12V 12AH batteries, (48V battery pack) usually lasts ~30 - 45 min

Check it out

https://www.youtube.com/watch?v=e6LV0A3l6jo
 

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Discussion Starter #3
Thank you, much appreciated. love the little kart, looks like a fun project.

At the size of those batteries, i could easily fit 8 to 12 (if i can squeeze in air flow) given how much space is available without the engine and gas tank. they are nice and small.

it's essentially one of these: http://chineseatvmanuals.com/images/fa-b50_wm.jpg

cheap 150cc Chinese ATV, engine was defective, and trying to go green and teach the kids something all in the same swoop.

thinking of even trying to add a transmission to the mix:
https://www.amazon.com/gp/product/B075RZGT5B/ref=ox_sc_act_title_2?smid=A36FCRXFCR9ZYN&psc=1





Howdy,

It depends

...on the area you have to put the (4) batteries into

...how much weight the vehicle can carry (safely)

...& how long you plan on him riding at a time

IMHO smaller is better


Remember

...the more weight you add

...the harder the motor has to work


I have used (4) 12V 12AH SLA (sealed lead acid) batteries like these on many go karts

https://www.amazon.com/ExpertPower-...id=1517327360&sr=8-3&keywords=12v+sla+battery



on my !Arriba! kart (48V 1,800W motor)

...the (4) 12V 12AH batteries, (48V battery pack) usually lasts ~30 - 45 min

Check it out

https://www.youtube.com/watch?v=e6LV0A3l6jo
 

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That will be a great project for you & your son

Save your money, time & effort

...skip the trans

IMHO

The koolest thing about converting from a gas engine to an electric motor

...whether it's a go kart, golf cart, motorcycle or even most cars is

...you don't need a transmission or a clutch


These 12V 12AH batteries weigh ~9 lbs. each

...(4) of them will add ~35 lbs. (4 x 9 lbs. = 36 lbs.)

...(8) batteries = ~72 lbs.

...or (12) batteries = ~109 lbs.

...that's a lot of additional weight on a small vehicle

How long do you plan on him riding at a time? (longer than 45 min.?)

...if not

IMHO

...keep 'er as light & nimble as possible


I have also used 12V 18AH batteries on karts too, they are

...~30% larger

...weigh ~ 12 lbs. each (4 x 12 lbs. = 48 lbs.)


Here is El Dingo, it's powered by (4) of the 12V 18AH batteries

https://www.youtube.com/watch?v=zYWuGJTC0jQ


Here is the same kart with (3) 12V 35AH batteries & a much bigger motor

...it was so heavy in the rear that the steering was more like a suggestion than a command

https://www.youtube.com/watch?v=AV0BQPm5JFo&list=PLoL6eIYWPO_ldEXj0hJX9nWGrLI8KmC7q&index=13
 

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Discussion Starter #5
Awesome Kart too!

The good news is the donor frame is an ATV, which means the batteries will be low center (preventing the needless wheelies)!

Looking to get a minimum of 30 min, though i'd like to get up to an hour.

how much time did you get with El Dingo in the two configurations? did the bigger batteries get you more time?


That will be a great project for you & your son

Save your money, time & effort

...skip the trans

IMHO

The koolest thing about converting from a gas engine to an electric motor

...whether it's a go kart, golf cart, motorcycle or even most cars is

...you don't need a transmission or a clutch


These 12V 12AH batteries weigh ~9 lbs. each

...(4) of them will add ~35 lbs. (4 x 9 lbs. = 36 lbs.)

...(8) batteries = ~72 lbs.

...or (12) batteries = ~109 lbs.

...that's a lot of additional weight on a small vehicle

How long do you plan on him riding at a time? (longer than 45 min.?)

...if not

IMHO

...keep 'er as light & nimble as possible


I have also used 12V 18AH batteries on karts too, they are

...~30% larger

...weigh ~ 12 lbs. each (4 x 12 lbs. = 48 lbs.)


Here is El Dingo, it's powered by (4) of the 12V 18AH batteries

https://www.youtube.com/watch?v=zYWuGJTC0jQ


Here is the same kart with (3) 12V 35AH batteries & a much bigger motor

...it was so heavy in the rear that the steering was more like a suggestion than a command

https://www.youtube.com/watch?v=AV0BQPm5JFo&list=PLoL6eIYWPO_ldEXj0hJX9nWGrLI8KmC7q&index=13
 

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Discussion Starter #6
couple more questions... my battery (DC) knowledge is limited...

I know more MaH means more drive time, but how does that relate to volts...
i see 12V 100Ah batteries for around 200, but with the drop in volts (48 to 12), will the controller/motor have issues?

also, how do you charge the bank of batteries once they are connected together for the 48V?
 

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Yes, the bigger batteries gave a longer run time

...but, not really enough to make up for the additional weight

...or loss of maneuverability & handling


I used to think that "bigger was better"

...or bigger batteries were the way to go

...but, as I tried the smaller, lighter batteries


I noticed,

...the motors didn't seem to work as hard or get as hot

...the karts were actually faster

...& they were a lot more fun to ride


Now, I start off as small & light weight as possible

...& upgrade (as necessary) from there
 

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couple more questions... my battery (DC) knowledge is limited...

I know more MaH means more drive time, but how does that relate to volts...
i see 12V 100Ah batteries for around 200, but with the drop in volts (48 to 12), will the controller/motor have issues?

also, how do you charge the bank of batteries once they are connected together for the 48V?

The voltage applied to an electric motor affects the RPM's

...most motors I have worked with produce ~70 RPM's per volt of input

...so @ 12V the motor RPM's would be ~840 RPM's

[email protected] 24V ~1,680 RPM's, @ 36V ~2,520 RPM's, @ 48V ~3,360 RPM's

So, @ 12V you would have a very slow ("power wheels" slow) type ATV


Also, the low voltage cut-off of a 48V speed controller is ~41V

...so, a 12V battery, no matter how big, (large AH) can not provide (nowhere near) enough voltage to power a 48V speed controller


I just use a small 48V battery charger for electric scooters on my go karts

...like this (under $30.00 delivered) :D

https://www.ebay.com/itm/48-Volt-2-...152157?hash=item20e7d0765d:g:ALEAAOSw32lY0wuL
 

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Thanks again for the detailed info! that seems to clear a lot up!.

outside costs, what are your thoughts on these batteries?
https://hobbyking.com/en_us/zippy-compact-5800mah-5s-25c-lipo-pack-xt90.html

thinking 3 would give me 55.5V... but it seems strange given the mah is 4x the other batteries (or i'm not understanding them right)

Those are for remote control cars & planes

...not a vehicle a person can ride in or on

mah (milli amp hour) like divided by 1,000

(5,800 mah = 5,800/1,000 = 5.8AH)

So, (3) of them, wired in series, would only give you an (55.5V 5.8AH) battery pack
 

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Hi Ama

If you use SLA's as recommended by Functional and discharge them by 80% they will last for about five or six cycles
NOT what you want!

The batteries are the most important part of any project of this type - if you are OK with 5 or 10 minutes of run time then use Lead

If you want 30 minutes or an hour then you will need to bite the bullet and move into the 21st century

Then it is how much you want to spend -

BEST would be some Leaf modules or a Chevy Volt module
like this

https://www.ebay.com/itm/Lith-ion-C...687242?hash=item2a99b9584a:g:qCcAAOSwUchaSnD5

Next best would be batteries for an RC car - these are very light - will give lots of power
BUT these are the "burn the house down" batteries and need to be treated with a lot of care and a smidgen of paranoia
 

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Discussion Starter #12
Oops, didnt catch the mah vs ah on the batteries. thanks, i wasnt catching that.

what about 2 of these instead?
Battery

with this controller:
https://hobbyking.com/en_us/turnigy-dlux-250a-hv-14s-60v-esc.html?___store=en_us

and this motor?
https://hobbyking.com/en_us/turnigy-rotomax-150cc-size-brushless-outrunner-motor.html?___store=en_us




Those are for remote control cars & planes

...not a vehicle a person can ride in or on

mah (milli amp hour) like divided by 1,000

(5,800 mah = 5,800/1,000 = 5.8AH)

So, (3) of them, wired in series, would only give you an (55.5V 5.8AH) battery pack
 

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Those batteries would do - BUT charge them on a metal plate - Just in Case

That motor is designed for very high rpm and LOTS of air flow - great for an aircraft - no good at all for a kart
 

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Discussion Starter #14
Thanks

any objection to ones like these:
Batteries
?

Hi Ama

If you use SLA's as recommended by Functional and discharge them by 80% they will last for about five or six cycles
NOT what you want!

The batteries are the most important part of any project of this type - if you are OK with 5 or 10 minutes of run time then use Lead

If you want 30 minutes or an hour then you will need to bite the bullet and move into the 21st century

Then it is how much you want to spend -

BEST would be some Leaf modules or a Chevy Volt module
like this

https://www.ebay.com/itm/Lith-ion-C...687242?hash=item2a99b9584a:g:qCcAAOSwUchaSnD5

Next best would be batteries for an RC car - these are very light - will give lots of power
BUT these are the "burn the house down" batteries and need to be treated with a lot of care and a smidgen of paranoia
 

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Hi Ama

If you use SLA's as recommended by Functional and discharge them by 80% they will last for about five or six cycles
NOT what you want!

The batteries are the most important part of any project of this type - if you are OK with 5 or 10 minutes of run time then use Lead

If you want 30 minutes or an hour then you will need to bite the bullet and move into the 21st century

Then it is how much you want to spend -

BEST would be some Leaf modules or a Chevy Volt module
like this

https://www.ebay.com/itm/Lith-ion-C...687242?hash=item2a99b9584a:g:qCcAAOSwUchaSnD5

Next best would be batteries for an RC car - these are very light - will give lots of power
BUT these are the "burn the house down" batteries and need to be treated with a lot of care and a smidgen of paranoia

Duncan,

you did notice, were talking about a kids toy

(a HD kids size ATV but, still a kids toy)

You think it's a good idea to put a 2Kwh battery pack on a kids toy?


IMHO & from my personal experience

...for a kid size vehicle

...the 12V 12AH are the safest & most cost effective way to go

I haven't actually counted but, I seem to get hundreds of cycles out of them

...& as I said ~30 - 45 min run time, every time

I use these batteries on

Desteny's kart https://www.youtube.com/watch?v=4RjUPNhhPoE&index=3&list=PLoL6eIYWPO_keNZBEhfrew8UB5maK25Nl

Winston's kart https://www.youtube.com/watch?v=YZ6bcBy1O1M&t=11s

Zero https://www.youtube.com/watch?v=TCzH-m-mEgQ

& I did several test on

E-lemon-aid (with a 24V 450W brushed ) https://www.youtube.com/watch?v=n1aysgJYGQ8

(a 48V 1,000W brushed motor) https://www.youtube.com/watch?v=AxKkIaE2feY&t=1s

(& with a 48V 1,800W brushless motor) https://www.youtube.com/watch?v=3yzOS4cE424&t=1s

...all with 12V 12AH SLA batteries

(some are over (3) years old, heavily used & still going strong)


* PLEASE, DO LOTS OF RESEARCH FIRST

DO NOT PLAY WITH LITHIUM BATTERIES

...until you know "more about them"

...what your doing

...& how to handle them "safely"
 

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Thanks

any objection to ones like these:
Batteries
?
Those would be OK
But a Chevy Volt module would be
A bit more expensive
Four times the capacity
And because it's OEM design and quality - much safer and more reliable

But to Functional's point with any of these you do need to do a bit of studying and be careful
 

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Discussion Starter #19
I am copying this!...
https://www.youtube.com/watch?v=3yzOS4cE424&t=1s

that 48V setup is fast enough for him! espically with that low/mid/high switch configuration.

Probably up the batteries a little tho 18Ah
or 35Ah


Duncan,

you did notice, were talking about a kids toy

(a HD kids size ATV but, still a kids toy)

You think it's a good idea to put a 2Kwh battery pack on a kids toy?


IMHO & from my personal experience

...for a kid size vehicle

...the 12V 12AH are the safest & most cost effective way to go

I haven't actually counted but, I seem to get hundreds of cycles out of them

...& as I said ~30 - 45 min run time, every time

I use these batteries on

Desteny's kart https://www.youtube.com/watch?v=4RjUPNhhPoE&index=3&list=PLoL6eIYWPO_keNZBEhfrew8UB5maK25Nl

Winston's kart https://www.youtube.com/watch?v=YZ6bcBy1O1M&t=11s

Zero https://www.youtube.com/watch?v=TCzH-m-mEgQ

& I did several test on

E-lemon-aid (with a 24V 450W brushed ) https://www.youtube.com/watch?v=n1aysgJYGQ8

(a 48V 1,000W brushed motor) https://www.youtube.com/watch?v=AxKkIaE2feY&t=1s

(& with a 48V 1,800W brushless motor) https://www.youtube.com/watch?v=3yzOS4cE424&t=1s

...all with 12V 12AH SLA batteries

(some are over (3) years old, heavily used & still going strong)


* PLEASE, DO LOTS OF RESEARCH FIRST

DO NOT PLAY WITH LITHIUM BATTERIES

...until you know "more about them"

...what your doing

...& how to handle them "safely"
 
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