LiPo Battery Manager Offers Dual Rails and Fuel Gauge for Remote Applications

Some projects require portable power, such as those for portable devices or situated in remote locations. This is where Manual Alfonso's LiPo Battery Manager comes into play, as the tiny, portable, all-in-one unit can be utilized as a battery charger, complete with dual rails (3.3V and 5V) and a handy fuel gauge that lets users know when its time for a recharge. The term "all-in-one" denotes the devices' flexible compatibility for all types of single-cell LiPo batteries and its various functionalities for battery monitoring applications.

Battery charging is handled by Texas Instruments' BQ24075 IC, and features a maximum charge current configurable via a DIP switch (1A, 500mA, 100mA), along with reverse current, short-circuit and thermal protection. The Battery Manager also offers Dynamic Power Path Management (DPPM), where output is active whenever a source is connected to USB or BAT, which provides power to projects even if the battery has died. The input current from USB is shared and balanced between charging the battery and powering the system load at OUT.

The device is equipped with battery supplement mode as well. "During the charging process, when the output current exceeds the limit configured by DIP switch (1A, 500mA or 100mA), the battery supplements the system load without any regulation, so max current provided by your battery, explains Manuel on his Tindie product page. "You can disable the system with a toggle switch. When off, the battery will be disconnected to system output, and all charge will be disabled. When ON, two LEDs indicate a valid input charge detection (ON) and the battery charging process (CHG)."

As mentioned earlier, the Battery Manager is outfitted with a BQ27441-G1A fuel gauge from Texas Instruments, which uses the company's Impedance Track Technology to predict battery capacity and other operational characteristics accurately. The IC is driven by a STM32G031G8U6 microcontroller and displays a wealth of information, including State of Charge, Temperature, Average Current/Power, Remaining Capacity, Voltage, Design Capacity, Full-Charge Capacity, and Health. The 18650 LiPo Battery Manager is currently available on Tindie for $20.

Beware: 18650s are like little bombs if you don't handle them properly.