Do You Know These Are the Batteries Used in an Electric Vehicle?
Electric vehicle battery, the power source for propulsion is the main component of an electric vehicle. Rechargeable batteries (secondary batteries) are the source of energy for an electric vehicle.
Different battery technologies are used in an electric vehicle based on their advantages, applications, and cost. The distance that can travel by an electric vehicle depends mainly on the capacity of the battery.
The size and cost of a vehicle increase as more battery is added to the vehicle. I would like to mention here that if the battery is not up to the mark, the performance of an electric vehicle would be poor. Please read My Experience with Electric Scooter!
Cost of electric vehicle batteries show a decrement in the last few years and it will further decrease since automotive industries focus on low cost, high efficiency, high capacity battery development. Tesla motors established a Gigafactory for battery production.
Desired characteristics of Electric Vehicle Battery
Electric vehicle batteries are expected to have the following characteristics.
- Deep cycle battery
A deep cycle battery can discharge almost up to a maximum of its capacity. They can be discharged up to 20% of maximum capacity but usually, it caps maximum discharge value to 45% for longer life span.
- High Ampere Hour capacity
Distance traveled by the vehicle in a single charge depends on the capacity of the battery. A high ampere-hour battery could drive the vehicle for a longer distance which the driver expects from his EV.
But the size and cost of the battery increases as ampere-hour capacity increases. It leads to install high capacity motors in the vehicle.
- High power to weight ratio
- High energy to weight ratio
Weight of battery matters in electric vehicles and it should be as light as possible, mainly for improved range, and life. You shall read: The Life expectancy of electric vehicle: How long an EV lasts?
- Low cost
It’s a recommended characteristic to reduce the overall price of electric vehicles and popularize them. The future of electric vehicles would definitely be affected by the cost of the vehicle. Running and initial costs should have been less than that of IC engine vehicles to get acceptance to EVs.
Common Electric Vehicle Batteries
Commonly used electric vehicle batteries are Lead-acid, Nickel-metal hydride, Lithium-ion, Zebra, etc. Short information about the electric vehicle battery is given below.
Traditionally electric vehicle has used Lead-acid battery due to their matured technology and low cost. But the life of a deep-cycle lead-acid battery is lower than that of other battery types.
The life span of a lead-acid battery is around 2 to 3 years. The lead-acid battery is now limited to a few electric vehicle battery applications due to the drawbacks.
Nickel metal hydride batteries are long-life batteries compared to a lead-acid battery. They are considered as a matured battery technology now.
Energy density is more in Nickel-metal hydride batteries. Even though the charging and discharging efficiency is lower than that of lead-acid battery, Nickel-metal hydride batteries position at the top with their long life and energy density suitable for electric and hybrid electric vehicles.
Lithium-ion batteries are the most common batteries used in recent electric vehicles. High energy density, power density, and charging efficiency are the advantages of Lithium-ion batteries.
The energy density of 200 Wh/kg and more than 85% of charge/discharge efficiency makes Lithium-ion batteries suitable for an electric vehicle.
The weight of the vehicle significantly reduces due to the above-mentioned advantages of the battery. But the life of a lithium-ion battery is not that impressive. It ranges to a few 1000 charging cycles.
Ultra-capacitors are another method to store electrical energy for electric vehicles. Ultra-capacitors have very high power density and low energy density.
A combination of battery and ultra-capacitor can be used in electric vehicles to overcome a few drawbacks and to extend the life of the battery. Momentarily available electric energy from regenerative braking can be stored in ultra-capacitors and eventually use to charge a battery.
Conclusion
The electric vehicle battery is an important component in an electric car that affects the size, cost, and range of the vehicle. Different battery technologies are being used in an electric car.
A consistent reduction in the cost of electric vehicle batteries would result in the overall cost reduction of EVs.
Originally published at https://getelectricvehicle.com on December 31, 2017.
