A simple method of charging a battery from a higher voltage battery is shown in the circuit below to the left. Only one resistor is needed to set the desired charging current and is calculated by ...

In an earlier blog post I did a teardown analysis of the XL4015 DC-DC Buck Converter module. I recently received an improved version of the same module. I purchased it from an online seller in China.

Using pulse current charging, or a constant current divided with a few short breaks, lithium-ion batteries hold up better over hundreds of charging cycles and can last twice as long. When you purchase ...