Rechargeable Lithium Ion Batteries

Hello Everyone!

I am planning to make a rear bike light, which has rechargeable batteries through USB. I then decided to use Lithium Ion Batteries for it. But the problem is that I dont know what parts I need.

It should be able to light up 4 COB LEDs (Each rated 12V, photo given)

Till now, after looking at several other instructables, I am able to say that:

1. It needs a steup transformer from 5V TO 12 V - TP4056



2. It needs some sort of protection like:

3. Also do can I allign three 3.7V Lithium Ion Batteries to make 11.1V?

Please help me out


Anshu ARyesterday


You need to be more specific about the LEDs that you are thinking to use.

Some of the 12V SMD LEDs are really kind of hungry for current. And they can draw a lots of current that a lithium ion battery cannot provide.

Include the link of the LEDs that you are thinking to use. As that will be the starting point for choosing other electronics and components.

Also, I've found that lithium ion batteries cannot provide a lot of current. So, lipo batteries are the solution.