Accu discharger (accugraph)
Description:
My brother builds electrical model aero planes driven by NiCd/NiMh/LiPo rechargeable batteries and he is therefore interested in keeping these rechargeable batteries in good shape, as they are quite expensive. He has therefore build the Accugraph, an rechargeable battery discharger and data collector. The apparatus can hold data from up to 250 discharge cycles (200.000 10bit samples) from up to 99 predefined rechargeable batteries. The discharge data can later be transferred to a PC through a RS232 serial port. The design is build around a 18F4620 PIC microcontroller, 8x24LC256 I2C serial eeprom, a DS1621 temperature measurer used to warn when the heat sink is hot.
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The main board containing the 18F4620 PIC, a 1Hz time reference, the MOS-FET's used to switch on the effect resistors. Updated to the newest firmware version 7! Note you will have to change the PIC to a 18F4620 to use the new firmware.