could the wallbuys 10 w floodlight be modded for battery use?

I have 2 of these on their way with other stuff from the christmas sale.

(it also looks very much like one that fasttech sells but i’m not sure how wallbuys can sell them for half the fasttech price even without 50% off that i used…)

do you think it would be possible to modify them so you could use them with batteries instead?
maybe someone have ordered one of these from wallbuys or some other place?

I think it could be a good portable work light for my father if it could be used on batteries after some modification.

You would need to figure out the vf of the LED and then match it up to a battery and a driver.

just measure the volts between positive and negative connection on the led, or am i thinking wrong there? (it’s 1 am here in Sweden…)
and then we’ll see if i can find a suitable driver as well.

These are almost always a 3x3 LED array chip. Drop in one of these drivers:

You may need 13-14V (car battery voltage) to get full output. That driver can go to 30V.

I modded mine with a triple Nichia 219 star:

I’m curious about that driver. It’s being sold as a 10W 12V driver but it looks like the 4115 is rated at up to 30Vin (and those rectifier diodes are rated at 40V and 1A) so is this really a 30W (30V @ 1A) driver in disguise?

Max voltage is 16 or 25V. But you can change two capacitors…

The ones I bought from Lightake had a 35V electrolytic cap, but they stopped selling them. The latest ones seem to have a 25V cap.

That small ceramic cap (rated voltage is unknown) is connected from the +Vin pin to the mosfet switch output. It is not shown in any of the PT4115E documentation and is not used on any of the smaller form factor M16 drivers… it can probably be removed.

Theoretically it is a 30+ watt driver, but in the real world is limited to 20-25W. They come with the current sense resistors set to 750 mA (not 1 amp). I modded one for the rated 1.2A output and it quickly went into thermal shutdown. If you parallel the sense resistors with a 1 ohm resistor, you get around 950 mA out, and it seems to work fine.

You need to check the voltage rating of the electrolytic cap on the board. I have seen boards with 35V and 25V caps. Some of the boards have a small ceramic cap of unknown voltage rating that is connected between the +Vin and SW pin (mostfet switch output) of the chip… it can probably be removed.

If you are driving the board with DC power in (and are careful not to reverse the power supply polarity) you can bypass those 4 diodes in the input bridge rectifier circuit and get better efficiency out of the board (those diodes eat around 1W at 1 amp). It also gives you around 1V more headroom on the input voltage requirement.

I used one of these drivers in my Waldmann lighted magnifier retrofit and am running around 24 watts into it. See

I drive one of those type leds off of a 12v battery with a 1ohm might be 1w resistor and they seem to work fine for me.

Probably not the best way but its functional.

It is HF filter.

Here’s a similar review:

is probably there to suppress radio noise from switching transients. It can also help to protect the mosfet from static damage. There doesn’t seem to be any benefit to removing it, but some downside.

I used the reservation service to order three of them. I’m probably going to use two on AC power, and one for toying around with battery powered. 12V DC drivers for these 3x3 1W LED modules are easy to find for a few dollars. I’ve seen the enclosure before, there’s a fair amount of room in the back compartment, however, I’m not sure there’s enough for 3x18650 cells. If they do not fit, I’ll probably go with some kind of Li-Poly pack, once I have exact dimensions.

The only reason to remove it would be if you want to run the driver at over 25V and if that cap is rated at 25V and you don’t have a higher voltage replacement available.

i’ve been thinking again about modding one for battery use.
it’s my father’s birthday tomorrow so he will get one of these that i have changed to swedish cord. i will ask him if he would like to have it modded for portable use.

here’s the parts i thought would be good using for that mod:
20mm xm-l star
1-mode driver (might not want highest output, but rather acceptable runtimes for a worklight)
tp4056 charging board
14500 battery holder
3-pin toggle switches

My thoughts goes like this:
change led and install driver somewhere.
I would use 2x14500 batteries in separate battery holders.
the driver is for single batteries, and I would use 2 switches; one for on/off(charging) and one for selecting battery A or battery B.
When switched off you could connect the charger to usb, and charge either battery A or B, depending on the battery switch.
i’m a bit worried that there might be some parasitic drain if i combine off state with charging state. Does anyone know anything about that?

it’s very late here, so maybe i don’t make much sense. but do you think this would be a good mod for this light?

Instead of switching between cells, why not just put them in parallel?

good question!
i guess i thought it would be safer treating them as separate cells, and also you know when you’ve used half of the available power.
if i bought protected trustfire flames 14500, would it be as safe to just use them in parallel instead of the switch-based setup? both while running the light, and when charging the batteries

For discharging, it would be fine either way, just less of a burden(in my opinion) to have them in parallel.

For charging(especially using *fires) it would be safer in the switch setup if you only plan on using a single charge circuit.

I plan on using 18650 cells… I thought they would fit. Nanjg105 3 mode and a usb charger board, driving a mule XM-L. I already have the bits for this, all I need is time.