Charging Curve for Electric Vehicles
While filling up the gas tank of your ICE (gas powered) vehicle, it typically does not communicate back to the gas station. For instance, you cannot monitor the real time status of your car’s gas tank as the station does not get this data from the car.
On the contrary, an EV charging process involves continuous communication between the charger and the EV resembling two love birds chirping at each other! The main goal is to ensure that your EV gets charged optimally based on the charging curve of its battery, but what is the “charging curve” and why is it important?
An EV charge curve refers to the rate of charging (kilowatts) over time as an electric vehicle’s battery charges from a low state-of-charge to a full charge. Analyzing and understanding charge curves is important for several reasons:
- It provides insights into your car battery’s charging characteristics and capabilities under different conditions.
- It shows the maximum charge rate the battery and onboard charger can handle, also known as the peak charge rate.
- The shape of the curve reveals different charging phases like rapid charging, tapering, and full charge.
- Charge times for key phases can be determined from the curve, which are important EV performance metrics.
- It shows how the battery management system modulates charging current/voltage to stay within safe operating limits.
- Environmental factors like battery temperature greatly influence the charge curve shape and times.
- The curves allow charger power levels and electrical infrastructure to be appropriately sized.
- Irregularities in the curve can indicate potential issues with the battery or charging equipment.
- Comparing charge curves for different EVs gives insights into battery technologies and charging capabilities.
In summary, carefully analyzing real-world EV charge curves helps improve charging equipment design, battery management algorithms, driver education on charging characteristics, and other aspects of electrification. It brings together many important technical facets of EVs and charging infrastructure.
