This project is an automated hardware and software tool for aging batteries in a precise fashion. The repo includes both hardware schematics and firmware.

HARDWARE

The aging process is done by repeatedly charging and discharging the battery. The hardware therefore switches between a charging mode and a discharging mode. Charging is done using a bi-directional DC/DC converter powered by a benchtop supply. Discharging is done via a DC/DC converter, carefully controlling a fet that shorts the battery to ground. Current is measured using a shunt and op-amp. The PCB is divided into five charging sections so that multiple batteries may be aged simultaneously. The system is controlled using an STM32F0 MCU. Also supports injecting a small AC ripple voltage during charging and discharging, which is used to measure the battery's impedance in real time.

FIRMWARE

The firmware is based on the STM HAL libraries. Features include:

• Independent charge/discharge settings for each battery
• Constant current / constant voltage charging, low-voltage disconnect
• Programmable load for discharging
• Injection of small AC ripple voltage
• Data collection and reporting

The firmware is Arduino based to make development easy (though I use the Arduino makefile to make customizing and automation easier in Linux). Features will include: + Independent charge/discharge settings for each battery + Serial communication via FTDI cable. With a Raspberry Pi attached, can be monitored via SSH. + Safeties ?!