The protection system for four Li-Ion cells with a voltage of 14.8 V. The module has the function of charging the cells, discharging and protecting against excessive discharge. The cells can be discharged with a continuous current of up to 18 A

The protection circuit for one Li-Ion cell with a voltage of 3.7 V. It has the function of charging, discharging and over-discharge protection. The cells can be discharged with a continuous current of up to 8 A

Step-Down DC-DC converter module based on the D24V150F7 chip. Input voltage 9..40V, output voltage 7.5V (max 15A). Pololu 2883

This synchronous switching step-down (or buck) regulator takes an input voltage of up to 40 V and efficiently reduces it to 3.3 V with an available output current of around 15 A. Pololu 2880

Step-Down RT8272 converter with adjustable output voltage in the range from 5 V to 12 V, input voltage from 5 to 24 V and a maximum output current of 3 A

DC-DC Step-Down converter module AP63203 with an output voltage of 3.3 V, an input voltage of 3.8 to 32 V and a maximum output current of 2 A. SparkFun COM-18357

BMS system for five Li-Ion cells with a voltage of 21 V. It has the function of charging with balancer, discharging and over-discharge protection. The cells can be charged with continuous current up to 60 A and discharged with current up to 80 A

The trigger module is designed for chargers PD 2.0 and PD 3.0. It is equipped with a USB type C input and USB typ A output. Allows you to power devices with 5 V, 9 V, 12 V, 15 V and 20 V and test chargers by replacing the PD device