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idea on powering up LED using Batterys for an Art Project

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Shay

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hi all ! :)
so i want to light up 20: 10w White Led 9-12V .
eventually i want to power them by either constant power, or battery packs.
but for the first stage of the project i'd want to use some batterys to light them up.

my question:

can i just connect 6 AA batterys directly for the white LED leds ?
i was toying in my head about just adding two 9V batterys to connect to all of that, but wouldn't that be too much ? (also 6AA batterys are easyer to get by)

does it batter if i light them up using 9 or 12 v ? will it change their Lumina power (will they become more bright) ?

and if so will the battery's be safe connecting them direct and give e the brightest they can go ?

also i want to not use heat sinks if possible...since i didn't really find them in ebay.

here are the lights i'm talking about

**broken link removed**

and here is the wire copper i'll solder all the led's to >

**broken link removed**

hope this a good one ?


also i'll add a simple drawing of my peace of what i want to achieve

thank you guys !!!! you are awsome

Al
 
hi,
I am using exactly the same LED's, you should not power them directly from a 12V battery as they will quickly cook.

Try 9V at approx 500mA rather than the 1Amp required at 12V or use a current limiting circuit or PWM.

EDIT:
That copper wire is Aluminium .!
 
hi,
I am using exactly the same LED's, you should not power them directly from a 12V battery as they will quickly cook.

Try 9V at approx 500mA rather than the 1Amp required at 12V or use a current limiting circuit or PWM.

EDIT:
That copper wire is Aluminium .!

sorry, here is an updated wire >

**broken link removed**

wait so if i'll have 6AA batterys that's 9V isn't it ?
couldn't i just connect it like this straight ahead to the lights ?
using a battery connector or something ?

i could buy somthing like that

**broken link removed**

to make my voltage more powerfull, but i think i don't need to do i ? i mean i'm giving them with 6 AA batterys exactly 9V... isn't it the best way to go ?

do you have a link for heat sinks for this leds ?

i guess my question is why to boost the voltage from the batterys just to lower it later to what it used to be in the first place... ?
 
Last edited:
Using AA batteries direct means the brightness will be very high on fresh cells and cause heat problem for LED and perhaps for battery, then the brightness will decay 90% quickly as cell voltage only drops 10% then last for a long time. It "may seem " efficient and cheap but only good for very short term by underpowered by low Wh capacity of Alkaline.

Without a good heatsink you can burn finger at max power, which may be size of small PC-CPU type heatsink. If it feels too hot to touch, then poor thermal/electrical design.
 
Using AA batteries direct means the brightness will be very high on fresh cells and cause heat problem for LED and perhaps for battery, then the brightness will decay 90% quickly as cell voltage only drops 10% then last for a long time. It "may seem " efficient and cheap but only good for very short term by underpowered by low Wh capacity of Alkaline.

Without a good heatsink you can burn finger at max power, which may be size of small PC-CPU type heatsink. If it feels too hot to touch, then poor thermal/electrical design.

then what is your suggestion for me to use , maybe somthing like that >

**broken link removed**

that will allow me to make the voltage weaker ?

and for the heat sink do you have a link to what i need on ebay ?

i found a youtube video that shows somthing like what i want to do, (around) i can't really use hies lights becouse it's 30V lights.. and i have the 9-12V.. but hies design should work with 9-12V led's right ?
i just need the Converter Module i linked above to get the voltage to around 7-8V.. yea ?




REALLY MY DESIGN IS REALLY SIMILAR TO THIS IN THE VIDEO SO MAYBE YOU CAN SUGGEST A HEAT SINK SULOTION FOR SOMTHING LIKE THIS ? maybe with links too that would be awsome !

maybe somthing like this >
**broken link removed**

and stick it with a thermal paste sticker or somthing ?
 
Last edited:
hi shay,
Watched the video, I think the paper clip method is awful.
Get a metre of 15Amp 3 core Solid house mains wire from your local hardware shop, strip the insulation off, it will make the connections easier.

Note he is using approx 20 off 32V working LED's, yours are only 9v thru 12v, so run yours at 9v and check the temperature.

If you wire 20 LED's in parallel operating at say 9v 500mA that is 10Amps!!!, I would not expect 4 * AA batteries to last very long with that load.

E
 
It depends how long you need the Light for and how well regulated and life of battery needed.

This application for camera video ( short term) is suitable for short battery power. or flash. .

As LED quality on Ebay has no tolerant, expect wide variation and cheaper quality, more bluish colors on cool white etc.

That video uses much less than rated power which may be a good choice for you to regulate voltage for 10 second finger test.
Lipo pack is best to use for long term use such as those on cordless drill, unless you like to buy cheap alkaline by 100 pc qty.

It is better to define your acceptance criteria for the project in terms of;
- CCT colour, brightness in lumens ( to reflect light power) or mcd (to look at light ) , minimum battery time., control, stability of brightness

If you already have the LED strips of 5m length , each R in each series of 3 LEDs determines current rise above 2.6 past 3.1V per LED. This allows dim use from 9 V to full power at 14.2 on car ( for most!) or 12V nominal if specified as max.!
 
It depends how long you need the Light for and how well regulated and life of battery needed.

This application for camera video ( short term) is suitable for short battery power. or flash. .

As LED quality on Ebay has no tolerant, expect wide variation and cheaper quality, more bluish colors on cool white etc.

That video uses much less than rated power which may be a good choice for you to regulate voltage for 10 second finger test.
Lipo pack is best to use for long term use such as those on cordless drill, unless you like to buy cheap alkaline by 100 pc qty.

It is better to define your acceptance criteria for the project in terms of;
- CCT colour, brightness in lumens ( to reflect light power) or mcd (to look at light ) , minimum battery time., control, stability of brightness

If you already have the LED strips of 5m length , each R in each series of 3 LEDs determines current rise above 2.6 past 3.1V per LED. This allows dim use from 9 V to full power at 14.2 on car ( for most!) or 12V nominal if specified as max.!

i didnt understood the last paragraph at all lol ;-)
can you give me a link for a cheap lipo pack with a charger as i need to charge it somehow... on ebay ?

what i want eventually is to connect the lipo pack to voltage regulator and it to the two wores ill run the leds from...
and make sure it outputs 9v..
will that be good ?
and pls bare in mind im really quit a newbi at this...

i need it to last to one hour shows at an excibit.. the i can power it off... charge the battery for one hor or so and turn it on again...

in the end im runing everything inside a statue.... and it light the pretty big statue from inside ...
 
It is better to define your acceptance criteria for the project in terms of;

- CCT colour, brightness in lumens ( to reflect light power) or mcd (to look at light ) , minimum battery time., control, stability of brightness

THen choose LEDs and power supply later.

Can you specify? If not then consider buying suitable standard LED bulbs and supply.
 
It is better to define your acceptance criteria for the project in terms of;

- CCT colour, brightness in lumens ( to reflect light power) or mcd (to look at light ) , minimum battery time., control, stability of brightness

THen choose LEDs and power supply later.

Can you specify? If not then consider buying suitable standard LED bulbs and supply.

i don't want to buy just a standart bulb and supply it.. i wouldn't learn anything from it... and i want to make it .. solder it and all...
i'll give you a diagram i'm making now to show you what i mean,
in GENERAL the idea is that i'll have
either Limo pack of some sort, it will connect to a switch, and later on to a Voltage Regulator, then from there to a 2mm Coper wire that will run on the 10W leds...
if the le'ds will be too hot i guess i'll turn the voltage down on the regulator, what the guy made in the vide is almmost dead on what i'm making only with diffrent modul and diffrent lights...
 
Here is a diagram of what i'm talking about and question will this work >

again the parts are:

Voltage Regulator >

**broken link removed**

Copper wire >

**broken link removed**

Light Bulbs >

**broken link removed**

as for the Lithium or the 6 AA batterys still not decided don't really know how much Lithium Battery + charger cost on ebay and which one do i need.

but is this set up good ?

will i still be needing small heat sinks even though i'm putting the voltage at 9V.. ?


**broken link removed**
 
The biggest risk is if each LED is not from the same batch and/or are rejects from some customer perhaps due to high Vf or low Iv or off colour.

THe next is you inexperience with desired power level is far beyond your conceptual design..

When they are not matched , Array with the lowest Vf draws most of the current. The ESR is around 1 Ohm for this type @1W per LED in a 3s3p array. still giving 1 Ohm ESR total. If you get the LED's and find they are not well matched by measuring the current with a fixed voltage like 9.0V then a custom (<~1Ohm) series power resistor must be added to each of the brighter LEDs to dim them and equalize the current when running in parallel, to the same as the others and also prevent thermal runaway if driving them to max current from a voltage source in this range.

According to the specs, it may take 9 to 12V to achieve 10W which means the ESR can range from 1 to 4 Ohms which is poor quality.

If you want to make a current limiter that drops low voltage then you can buy or may one.
You may not use full 10W due to your choice of not using the best heatsink required to achieve this rating and probably be limited to 1W using the 10 second touch rule.

Practically you would be better off using series 19.2V Lipo pack and limit the current with a 50mV shunt resistor, comparator and gate drive 10 mOhm MOSFET and running 12s2p strings of the LEDs and run at 10% of rated power in each string. This is far greater than most LiPo packs are designed to handle safely.

Until you understand that 24x 10W = 240W of heat is more than a soldering gun and learn how to design a proper heatsink, you will probably melt solder. !!

You will learn more by studying a good product with a 240W AC PSU than failing with a poorly conceived portable battery incapable of delivery of these power levels and incapable to removing the heat lost in the LEDs in a small area..
 
The biggest risk is if each LED is not from the same batch and/or are rejects from some customer perhaps due to high Vf or low Iv or off colour.

THe next is you inexperience with desired power level is far beyond your conceptual design..

When they are not matched , Array with the lowest Vf draws most of the current. The ESR is around 1 Ohm for this type @1W per LED in a 3s3p array. still giving 1 Ohm ESR total. If you get the LED's and find they are not well matched by measuring the current with a fixed voltage like 9.0V then a custom (<~1Ohm) series power resistor must be added to each of the brighter LEDs to dim them and equalize the current when running in parallel, to the same as the others and also prevent thermal runaway if driving them to max current from a voltage source in this range.

According to the specs, it may take 9 to 12V to achieve 10W which means the ESR can range from 1 to 4 Ohms which is poor quality.

If you want to make a current limiter that drops low voltage then you can buy or may one.
You may not use full 10W due to your choice of not using the best heatsink required to achieve this rating and probably be limited to 1W using the 10 second touch rule.

Practically you would be better off using series 19.2V Lipo pack and limit the current with a 50mV shunt resistor, comparator and gate drive 10 mOhm MOSFET and running 12s2p strings of the LEDs and run at 10% of rated power in each string. This is far greater than most LiPo packs are designed to handle safely.

Until you understand that 24x 10W = 240W of heat is more than a soldering gun and learn how to design a proper heatsink, you will probably melt solder. !!

You will learn more by studying a good product with a 240W AC PSU than failing with a poorly conceived portable battery incapable of delivery of these power levels and incapable to removing the heat lost in the LEDs in a small area..


ok i'm really a newbi so i didn't understoof like 3/4 of what you said...
but from what i understood your basicaly telling me,
my design won't work...
and don't do this project.. becouse i don't understnad in anything ?
and better for me to take apart a good product and see how it works then for me to make one from scratch ?
 
Why are you buying ebay junk that has no manufacturer's name and no detailed datasheet? Cheap or cheep, cluck cluck.
The LEDs are probably not all the same because they are not identical incandescent light bulbs, they are Light Emitting Diodes. Some need 9V and others need 12V. You can even out some of the voltage difference if you use a 15V power supply and a current-limiting resistor in series with each LED.
The tiny cheap power supply might set your home on fire and it is rated to power only 2 of those high power LEDs.
 
hi shay,
I would advise against using a cheap end 'wall wart' for your project, many burn outs have been reported in the UK.

How do you plan to mount the LED's on their heat sinks.?

Please tell us more about the actual project that requires lighting.
E
 
hi shay,
I would advise against using a cheap end 'wall wart' for your project, many burn outs have been reported in the UK.

How do you plan to mount the LED's on their heat sinks.?

Please tell us more about the actual project that requires lighting.
E

well i think it's either that or the 6 AA Batterys' or even 2 9V batterys (the square ones) so maybe it's better
keep in mind i Am connecting it to a voltage regulator to insure i'll output no more then 9V...

i'll mount the small hit sinks using a thermal pad... like this one >
**broken link removed**

but really will that tiny 1Cm heat sinks will do such difference ?
i only need the LED to be on like for 10 minutes at a time...

i told my project,
it's going to be a ring of LED' with the copper wire... exactly like he did in the video i linked..
the leds will be housed inside a small statue, i just loved the shape it makes in the final product in the video it's the perfect shape to mount on my statue.
it will only be on for like 10 minutes at a time.. every couple of days...just for people to see.
 
So the light is for short term intermittent use.

I would experiment using 9V, which should give ~500mA thru each diode, see how hot they get over a 10minute period.

Using 20 of these will give a VERY bright light.! I would suggest you try with say 10 and add more as required.

EDIT:
Look at this link compare lumen's/watt

**broken link removed**
 
So the light is for short term intermittent use.

I would experiment using 9V, which should give ~500mA thru each diode, see how hot they get over a 10minute period.

Using 20 of these will give a VERY bright light.! I would suggest you try with say 10 and add more as required.

i really like the design with the circle and all that takes in 20 of the LED's. it looked awsome... even if it's a bright light...

if it will be too bright i will just use less Volts in the Volts regulator..so that the lights will be dimmer... (or it won't make much difference and they will be like super bright anyway ?)


i have seen another video were a person uses 3 LED Rings... i was thinking about doing that design at first, and i do think that 3 rings will give MUCH less light then the 20 10W Lights i'm using in mine..
but i didn't liked hies design really much (how it looked like in the end) here is the video for that one >

 
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