An eGas Gauge for My eBike

[rgsparber]

Trying to measure the remaining capacity in a Lithium-Ion battery is tricky. If the battery is not sourcing current, the voltage can give a good estimate for a given battery. All bets are off when current flows. The voltage will drop as the current rises and then go back up when the current falls.

A much more accurate, but not perfect, method is to record the current over time. The battery has an ampere-hour rating, so it is just a matter of knowing when the battery is fully charged and subtracting the ampere-hours as they pass by.

This is what my eGas Gauge does. The hardware consists of 3 resistors, 2 capacitors, a toggle switch, a piezoelectric beeper, 3 AA batteries, and a $1.50 computer system on a chip. The complexity is in the software but you don't have to build or pay for that.

If you are interested, please, click here.


Thanks,

Rick