Chargers for 1S lithium batteries are everywhere, but what about when you need to use a 2S battery pack? 2S stands for a battery pack in which two cells are connected in series, so the effective maximum output voltage is 8.4V and the nominal 7.4V.

This linear charger is based on the HX6038 integrated circuit and allows 8.4V battery charging. There are indication LEDs for charging status, as well as a standard DC port for input and JST for output, also with pads in case you want to solder the wires to the input or output. There is also an option of connecting an NTC resistor to prevent the battery from overheating. It also comes with two jumpers for configuring the charging current, and by default it comes with a charging current of 500mA and 750mA can be adjusted. Be cautious if using higher currents, the board heats up and needs at least a passive radiator.

• Input voltage: 9.2V - 13V
• Charging current: 500mA, adjustable up to 750mA
• Dimensions: 32.5 x 21.3 mm

This board has been manufactured in Croatia by e-r.io: Blog, Github.