My Lectric XP eBike displays battery voltage as an indicator of remaining energy. When the current is zero, this strategy works fairly well. But when riding, the voltage varies as a function of current. A better way to estimate this energy is to keep track of the ampere-hours drawn from the battery. The first time I fully charge up my battery and then discharge it to what I call empty, the circuit learns this change in ampere-hours. From then on, I fully charge my battery, tell the eGas Gauge it is full, and system tells me the remaining energy. There are three output options. It can beep out the data within +/- 3%, drive an analog meter for continuous readout, or flash an LED to indicate Full, 3/4, 1/2, 1/4, or Empty. Complete details plus code are available here.
Comments