Enraged by the increasing environmental concerns and the limited availability of oil resources, the automotive industry has been looking for alternatives to fuel vehicles. Alternatives that do not utilize petroleum are not easy to find. The most promising solution seems to be battery operated vehicles. BEVs (Battery Electric Vehicles) have taken the automotive sector by storm and are a popular option. BEV operated vehicles are ZEVs (Zero Emission Vehicles) meaning that they do not use any form of diesel or petrol and thus do not produce any type of toxic gas. They help contribute to cleaner air and are eco-friendly. These vehicles run on electricity which can be generated through renewable and environment friendly ways. While most of BEV models utilize one type of battery, there are several different types of batteries that have been implemented in battery electric vehicles.
TYPES OF BATTERIES USED IN ELECTRIC VEHICLES:
1. Lithium-Ion Batteries
Lithium-ion batteries are currently used in portable consumer products like cell phones and laptops due to their high energy per unit mass compared to other electrical energy storage systems. It also has a high power to weight ratio, good performance, low self discharge and high energy efficiency. Most of the electric vehicles today use lithium-ion batteries. However, the chemistry used in consumer electronics and that of electric cars is different. There is an ongoing research to reduce costs and extend battery life cycles.
2. Lead-Acid Batteries
Lead-acid batteries can be designed to be high power, inexpensive, safe and quiet reliable. Low specific energy, poor cold temperature performance and short cycle life hinders their uses. Batteries that are high power lead acid are being developed but only to be used in commercial electric-drive vehicles for ancillary loads.
3. Nickel-Metal Hydride Batteries
Nickel-metal hydride batteries are mostly used with computer and medical equipment as they offer reasonable specific energy and power capabilities. These batteries have a longer life cycle than lead-acid batteries. They are also quiet safe and abuse tolerant. They are widely used in Hybrid Electric Vehicles. The drawbacks with nickel-metal hydride batteries is their high cost, self discharge and heat generation at high temperatures.
Ultracapacitors store energy in a polarized liquid between an electrode and an electrolyte. They provide vehicles extra power during acceleration and uphill driving and help recover braking energy. As the liquid’s surface area increases, the energy store capacitie increases too. They can be useful as a secondary energy-storage device in electric cars as they help electrochemical batteries level load power.