Constant Current vs Constant Voltage EV Charging: What’s the Difference?

EV charging algorithm

Whether you currently own an electric vehicle (EV) or if you’re planning to buy one in the near future, you should familiarize yourself with the different charging algorithms. EVs have become more advanced in recent years. According to the U.S. Environmental Protection Agency (EPA), EVs now have a median range of 234 miles. In other words, you can drive for over 200 miles on average before recharging an EV.

After the battery bank has been depleted, it must be recharged. There are different types of charging algorithms used by EVs, however. The charging algorithm defines the way in which the battery bank of an EV is recharged. Two of the most common EV charging algorithms are constant current and constant voltage.

What Is Constant Current?

Constant current is an algorithm for charging lithium-ion (Li-ion) batteries — specifically those used in EVs. As its name suggests, constant charging leverages a constant current. When charging an EV with constant current, the EV will receive the same current the whole time. The current won’t change while the EV is being charged.

What Is Constant Voltage?

Constant voltage is a Li-ion charging algorithm that leverages a constant voltage. A predetermined voltage is used to charge the batteries. The voltage won’t change while the EV is being charged. As a result, EVs are protected from overvoltage while in constant voltage charging mode.

Differences Between Constant Current and Constant Voltage

Constant current and constant voltage are EV charging algorithms. They provide the technical framework that’s needed to recharge the battery banks of EVs. The main difference between them is that constant current uses a current, whereas constant voltage uses a voltage.

They can both get EVs back on the road following a depleted battery bank. Constant current and constant voltage simply use different methods to recharge EV batteries. Constant current uses a fixed current. Constant voltage uses a fixed voltage.

Constant voltage will also protect EVs from overvoltage. EVs will receive a constant voltage when charging in this mode. Constant voltage will also help to fully charge batteries. It ensures that EV batteries are fully charged, resulting in the longest possible range for EVs.

In Conclusion

There are different charging algorithms available for EVs, including constant current and constant voltage. Some EVs even support both of these charging algorithms. Constant current is a charging algorithm that uses a constant, fixed current. Constant voltage is an alternative charging algorithm that uses a constant, fixed voltage.

Monroe Titan Support