Hi, I am new at this and was hoping for some guidance.

I currently have this setup for testing-

2s 18650 7.4V --> Constant Current Boost Regulator (XY-SJVA-4) --> 20W LED

I can't seem to find clear information regarding adding the ability to recharge via USBC as I have two 18650 running in series.

Is something like the attached photo suitable? It seems to vary from the tp4056 as it doesn't have load terminals....

Any advice would be much appreciated?

Thanks!

 

Do you want to add a charging led, or are you wanting to input voltage from a C usb?

 

Do you want to add a charging led, or are you wanting to input voltage from a C usb?

I want to be able to charge the 2s 18650 via USBC but not sure what component to use.

Essentially I am trying to mock up a rechargeable LED floodlight using the XY-SJVA-4 CC regulator.

Does that make sense?

 

Can I do this?

 

Hi, I am new at this and was hoping for some guidance.

I currently have this setup for testing-

2s 18650 7.4V --> Constant Current Boost Regulator (XY-SJVA-4) --> 20W LED

I can't seem to find clear information regarding adding the ability to recharge via USBC as I have two 18650 running in series.

Is something like the attached photo suitable? It seems to vary from the tp4056 as it doesn't have load terminals....
View attachment 315021
Any advice would be much appreciated?

Thanks!

I technically believe these are for single cell charging. However I did charge 2 batteries simultaneously with one basically identical but they were in parallel and not in series. I'm not sure if it would work in series. 18650s tend to be fire hazard if you're not careful. May I ask do you really need 2 in a series? Most flashlights work on lower voltage. A single 18650 normally pushes led flashlights harder than what was originally intended them. You could put 2 18650s in parallel and double your capacity and keep lower voltage. Then you could charge them together with a single charger and to top it off if a single cell were to lose its capacity it would most likely still function. However a series will provide you with a brighter light if the leds can handle the voltage

 

Yes, I know there can be an element of danger, hence wanting a better understanding before attempting anything, thanks for the concern.

The Boost Regulator I am using requires a minimum 5V input so parallel does not provide enough voltage.

I know I could make it simpler by parallel and a different regulator but I want to use the current module with the view of a higher wattage/voltage light in the future. Obviously providing I can do it safely!!

 

Yes, I know there can be an element of danger, hence wanting a better understanding before attempting anything, thanks for the concern.

The Boost Regulator I am using requires a minimum 5V input so parallel does not provide enough voltage.

I know I could make it simpler by parallel and a different regulator but I want to use the current module with the view of a higher wattage/voltage light in the future. Obviously providing I can do it safely!!

Technically you could use 2 of the charger pcbs and wire it with

Yes, I know there can be an element of danger, hence wanting a better understanding before attempting anything, thanks for the concern.

The Boost Regulator I am using requires a minimum 5V input so parallel does not provide enough voltage.

I know I could make it simpler by parallel and a different regulator but I want to use the current module with the view of a higher wattage/voltage light in the future. Obviously providing I can do it safely!!

Then what you need is a 18650 7.4V 2S BMS such as https://www.ebay.com/itm/4034808510...739237574&abcId=9307911&merchantid=5302020491

 

I technically believe these are for single cell charging

The board he showed supports 2S, 3S, or 4S. However, there is no provision for balancing.

 

The board he showed supports 2S, 3S, or 4S.

Oh my bad buddy. I had one almost identical and it did not. I'm sorry for being misleading. I shouldn't have jumped to conclusions but good news though!

 

Thanks for the replies.

Can you give any advice on if the way I want to wire up feasible/correct/safe? (Diagram in previous post)

Now you mention it, I forgot about balancing, any recommendations on a similar 2S module that has balancing?