DIY Sensor Night Light with LED Upgrade

How to modify an 8-LED solar motion sensor light into a bar-style sensor night light/flashlight?

If you're interested, keep reading!

The 8-LED solar motion sensor light looks like the one in the picture below.

Since the solar panel is too bulky and its shape isn't suitable for our purposes, you'll only use the internal circuit board and discard the outer shell.

Most of the bar-style sensor night lights you find online have a long, slim design. In addition to the sensor night light function, you'll add a constant lighting feature.

First, you'll need to use a laser cutter to shape the acrylic outer shell and place the sensor on one side. 

Next, you'll need to fix the circuit board in place using 3M double-sided tape.

For the light strips, you'll need to use aluminum-based strips, replacing the original LEDs with LG's 5730 LEDs. You'll also need to change the wiring from series to parallel. One strip will serve as the night light, while the other will handle the constant lighting.

To minimize thickness, you'll repurpose two old batteries from an iPhone 5, connecting them in parallel. Testing shows they can provide 1.7Ah of power with a 1A discharge.

You'll then add a 4056 module for charging, using a dual-purpose charging and protection circuit scavenged from a promotional item, and include a Type-C port for charging.

For wiring, you'll relocate the switch from the circuit board to the top of the unit, trimming the handle to match the height of the shell.

Once assembled, you'll add a segment of solder wire to limit the current in the constant lighting mode, which gives off a good level of brightness.

The night light feature is also functional, with a built-in current limiter on the board, making it ideal for use at night.

If you don't like the transparent acrylic look and think it appears too messy, feel free to swap it out for an opaque one.

Here's how it looks while charging:

And that's it! Finished!