Since quadcopters run on electric power, it’s very important having a decent battery charger to ensure your batteries last a long time and to get the most out of them. Its also important to have a quality charger from a safety point of view. This project is about making the4-channel smart Li-Po batteries charger with discharging and balancing functions.
We decided to build the system on the industrial ICs and STM32 controller as the main MCU.
LM25088 is responsible for DC power converting,
BQ24600 – battery charger,
BQ76PL536A – balancer IC.
We chose passive balancing method (bleed resistors) as the simplest and smallest type of balancers available.
should be able to work with external 36V input power supply and charge batteries from3S (11.1V) to 6S (22.2V) with the charging currents of 1A, 2A and 5A
should also support discharging batteries with the power up to 50W, data transmitting between charger and external device via I2C protocol and simultaneous charging of three batteries
temperature measurement of each battery block should be provided.
Balancing should be available both while charging and discharging there must be a possibility to manually change type of charging/discharging and to control the device via I2C with the help of special commands protocol (start charge, start discharge, start balancing, etc).
Technology & Work
Firmware development 1 p
Firmware/Hardware testing and optimization
MCU: STM32F401 IDE: Keil Power supply: 36V 15A input DC-DC converter: LM25088 Battery charger: BQ24600 Battery balancer: BQ76PL536A Measurement equipment: digital multimeters, ampermeters, oscilloscope, etc.