Charging board and battery pack for Light Design

I am a light designer based in Western Canada. I am looking at building a system to enable me to make my floor lamps portable (use on patio etc). I use 24v COB LeD’s with the biggest lamp being 20W. Ideally they should last for about 4-6 hrs on a charge and have a power pack that can be charged using USB or USB C. Can you advise if DigiKey have components that would be suitable and if so which components do you recommend for this type of project. All components need to be UL certified.

Thanks so much

Welcome to the forum.

I’m very far from an expert on available LED Lighting components so perhaps some other engineers here will have better information.

AFAIK, you will need to have a full custom system designed to provide 24V from portable batteries and have it charge via normal USB chargers. This is due to the inefficiency of shifting voltages at the high currents required for your 24V 20W lights and a 4-6 hour run time, 80-120Wh.

@PaulHutch Thanks for that.

I do think that I probably started at the wrong end of the spectrum here, which is kind of the way I work.
If we scale the idea back and say 10W at 12v (approx. 850mA). Really I need to find a system that will give me usable power for a sensible amount of time (no less than 4hrs) with convenient charging for my clients, hence the 5v USB cable. I can use either 12v or 24v LEDs (without adding new SKU’s to my inventory) I do have a really nice light engine that needs just over 3W @ 24v So that might be a good place to start.

Sorry for all the convoluted ideas here, this has been a back burner idea of mine for ages and I’d like to make it happen now.



In case nobody else has any ideas, you should consider buying a few similar devices that already exist in the market and disassemble them for component ideas. (e.g. rechargeable work lamps and camping lamps)

Reverse engineering someone else’s existing product is a common starting point for companies entering a new market.


Thank you for that. I’ll wait a little bit to see if I get a response here and failing that I will do just that.



Your LED voltage requirements would indicate you need a voltage boost circuit to either power your LEDs with a single cell lithium or boost circuit to charge your multi-cell battery pack. Unless you go with a USB Power Delivery charger.

Boost circuits add to design complexity. Also charging a multi-cell lithium battery pack adds to design complexity.

If you ran a number of discreet LEDs in parallel with their own current limiting resistors with a lower than 3.4VDC forward voltage you could run off a single cell lithium with no boost circuitry which would be a fairly straight forward 5V charge design.

Regarding your UL Certified components request most parts unless they’re something like a fuse or other kind of circuit protection device or power connector aren’t going to be UL Certified.

Somebody may have better ideas than I have on this.

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