{{template>:template:project | name=portable-led-bar | status=active | founder=[[user>lepi]] | repo=[[github>lepi00/portable-led-bar]] }} \\ \\ === DISCLAIMER: === === This is not yet a finished project intended as instructions but only a means to share progress on the project. === === This might be dangerous to attempt !!! === === If you attempt to follow any of this, you do it at your own risk. === \\ \\ === Adapting a mains AC led bar to work with a battery of 18650s === by [[people:lepi:start|lepi]](lepi at-a hackerspace.pl) \\ {{:projects:portable-led-bar_batteries.jpg?direct|}} {{:projects:portable-led-bar_voltage.jpg?direct|}} \\ \\ {{:projects:portable-led-bar_ingredients_r0.1_1024.jpg?direct|}} \\ \\ KiCAD files: [[https://github.com/lepi00/portable-led-bar/tree/main/kiCAD-portable-led-bar]] Revision 0.1\\ {{:projects:portable-led-bar_kicad_0.1.png?direct|}} \\ \\ === Intro === The purpose of this project is to adapt a 220AC UV LED-Bar to work with 18650 cells. \\ \\ I have just started learning electronics, and my knowledge is very basic. \\ \\ \\ == Specifications == The LED Bar - Light4Me LED UV 8 ^Characteristic ^Value ^Notes |Voltage: |AC110-240V, 50/60Hz | | |Power: |30W | | |Light source: |8x3W UV LED | | |Light angle: |65° | | |Light wavelength: |390-410 nm | | |Dimensions: |450 x 50 x 40 mm + 55 mm pins | | |Weight: |0,6 kg | | | | | | |LED driver inside (IP65): | | | |Model: |ZW0820 | | |Power: |27 W | | |Input: |AC85V-265V 50/60Hz | | |Output Voltage: |27-36V DC | | |Output Current: |600 mA ±5% | | |TA: |60 °C | | |TC: |80 °C | | \\ 18650 Cells ^Characteristic ^Value ^Notes |Datasheet: |(https://www.tme.eu/Document/e06617d885c58dfb3fecaf4abbe330c4/ICR18650-26H.pdf)["datasheet"] | | |TME Symbol: |Samsung ACCU-ICR18650-26H | | |Rated voltage: |3.63 V | | |Capacity: |2.6 Ah | | |Maximum current: |5.2 A | | |Charging Method: |constant voltage, limited current | | |Charging Voltage: |4.2 V ±0.05 V | | |Charging Current (standard): |1300 mA | | |Charging Current (max): |2600 mA | | |Diameter: |18.4 mm | | |Length: |65 mm | | \\ Battery charger - Tangspower TP-L8S20 Li-ion charger ^Characteristic ^Value ^Notes |Maximum Voltage: |8 * 4.20 V = 33,6 V | | |Charging Current: |2 A |Passive, PFC filter| \\ \\ \\ === The Story === \\ === Revision 0.1 === A friend of mine performs POI with POI-tails that are neon-yellow. The thing is made to shine in UV light. Some AC mains LED bars I have, revealed a lot of space inside the casing profile - more than enough to house 8 18650 cells. \\ The LEDs have a "PowerLed" package soldered in-series upon a pcb with no other elements, but most likely have some resistor inside the package, as multimeter LED tester does not show anything when testing a single LED. \\ \\ Remembering next-to-nothing about Electrical Circuits, I started designing a circuit, that would: - Power the LEDs from cells - Allow charging the cells without taking them out - If possible leave the original charger with mains connection \\ \\ First I considered two solutions: - LEDs and cells in parallel - Operating current would be 0.6 A * 8 = 4.8 A - Charging current would be 1.3 A * 8 = 10.4 A - LEDs and cells in-series - Operating voltage would have to be 26.9 V (3.36 V / LED) - Charging voltage would have to be 8 * 4.2 V = 33.6 V \\ \\ == Parallel... == - I have a TP4056 03962A Lithium Battery Charger with protection module - [[03962A description]](https://www.epal.pk/product/tp4056-lithium-battery-charger-with-protection-module/) - [[TP4056Datasheet]](http://www.haoyuelectronics.com/Attachment/TP4056-modules/TP4056.pdf) - Initially I thought that would be crazy to put 8 of these inside - Also wiring LEDs in parallel would if I understand correctly require to put at least 40 cm * 8 = 3.2 m of thick wire - that might be difficult. \\ \\ == In-series... == - A friend informed me to the fact, that I could use an external 33.6V charger which seemed to be easier. - And also that I could use LM317 to regulate current out of the cells to LED's - I decided to use a I/0/II switch and an IEC cord socket with the original LED driver if possible. \\ \\ Emeryth suggested: - to learn more about li-ion cells before I use un-protected or multiple cells - to put some protection between cells and the cell charger - to use a DC-DC converter instead of LM317 that produces too much heat - to rethink if I need all LEDs in-series \\ \\ === Next Steps: === - Research Emeryth's suggestions\\ - Find a solution to connecting the cells - decide whether to solder the cells (dangerous, potentially capacity hindering) - contact weld the cells (I don't have access to a contact welder) - design a 3d-printed casing for the cells with springs, that would slide into the LED bar casing - remember to discharge cells before in case of soldering \\ \\ Notes:\\ - https://pl.aliexpress.com/item/1000001962896.html\\ - https://lcamtuf.coredump.cx/electronics/