Adding LED to solar garden lights

Any issues if i add more LED in a solar powered garden lights ? Would I overheat the circuit if I add 3 or more LED in parallel, it currently has one pathetic LED. I only need the light to be on for about an hour, so battery life is not an issue. I would also be replacing the original LED for a brighter one

It should be fine. I'd try it on one first and see how it works after a week or two, then do the rest just to be sure though.

You may have an issue wiring three LEDs directly in parallel. Even from the same batch, LEDs rarely have exactly the same V-I curve, so wiring in this way will lead to one LED being much brighter, and another being much dimmer. You can regulate this with a series resistance for each LED (not a great way to do it because it hits efficiency, but it's the easiest and you already said that you don't care about battery life). The battery resistance may naturally regulate this so don't worry about it unless you definitely notice that the LEDs are not the same brightness. Even then, if you don't care then don't worry about it.

CoveAxe said:

... The battery resistance may naturally regulate this ...

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It won't. Each LED needs it's own resistor.

Gordon

You're going to find greatly reduced runtimes.

added 2 more led directly in parallel, sadly it did not do much to increase brightness, does the circuit divide the current into three ?

It doesn't work because the LEDS won't divide the current equally if they are in parallel (described in detail here). You will need to add resistors to each LED.

Sorry a bit confused, will adding the resistor make it brighter ?

CoveAxe said:

It doesn't work because the LEDS won't divide the current equally if they are in parallel (described in detail here). You will need to add resistors to each LED.

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No. Adding LEDs will only serve to divide the limited current available.
You'll be drawing more mA then is available and will run the battery down faster.
You need more wattage available to the LEDs.

How do I add more wattage to the LED ? battery life is not an issue, I need to make the light work for only 30 min to an hour.

FRITZHID said:

No. Adding LEDs will only serve to divide the limited current available.
You'll be drawing more mA then is available and will run the battery down faster.
You need more wattage available to the LEDs.

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OK, I think everyone's answers (including mine) were giving you conflicting ideas. Since you didn't give any idea of the circuit layout of the light, we have to make assumptions that may or may not be true, which leads to different answers.

Assuming the entire battery voltage with no current limit is available to the LED, then you will need to wire a resistor for each LED before putting them in parallel. Otherwise the LEDs will not have the same brightness. You lose efficiency doing this though. There's no shortage of guides on how to do this.

If there is a transistor circuit current-limiting what is going to the LED, then it becomes a lot more complicated and you'll most likely to do significant modification to get it to do what you want. Adding LEDs in parallel in this case will not increase brightness at all.

Based on guides like this, it appears to be the latter case. If you're handy with a multimeter you could get the circuit diagram and figure out what values you need to change to do what you want. Otherwise there's not much you can do.