National Battery Day commemorates the anniversary of Alessandro Volta’s birth in February 1745.
From powering home appliances to transportation to life-saving medical devices, batteries are everywhere and they play an incredibly important role in our daily lives. One battery we want to highlight is the battery used in electric vehicles (EVs). While internal combustion engine cars get energy from burning petroleum or diesel, an EV gets its power directly from a big pack of batteries.
These batteries are much like a larger version of the lithium-ion batteries in our cellphones. EVs don’t use a single battery like a phone. They have a battery pack comprised of thousands of individual lithium-ion cells working together. When the car charges, the electricity is used to make chemical changes inside its batteries. When it’s on the road, these changes are reversed to produce electricity.
EV batteries undergo cycles of discharge when driving and charge when the car is plugged in. Repeating this process over time affects the amount of charge the battery can hold. Most EV manufacturers have a five to eight year warranty on their batteries. First, electric car batteries were projected to last 8 to 10 years, and now the current prediction is they will last 10 to 20 years before they need to be replaced.
How a battery and the car’s electric motor work together is surprisingly simple. The battery connects to one or more electric motors, which drive the wheels. When you press the accelerator, the car instantly feeds power to the motor, which gradually consumes the energy stored in the batteries.
Electric motors also work as generators. When you take your foot off the throttle, the car begins to slow down by converting its forward motion back into electricity, which happens faster if you hit the brakes. This regenerative braking recovers energy that would otherwise be lost, storing it in the battery again and so improving the car’s range.
For more information or to find out if an electric vehicle is right for you, visit our Electric Vehicle Info page.