EV Chapter 7: EVs and batteries
One of the major components of EVs is their energy storage systems, i.e., batteries, which are essential for all types of EVs including, hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and pure electric vehicles. Eventually, a huge number of vehicles with enormous batteries inside will hit the roads in the coming decades. Each of those batteries will contain tens of kilos of yet-to-be-mined materials. Under this chapter, we discuss various types of energy storage systems, which include:
• Lithium-Ion Batteries
Because of its high energy per unit mass compared to other electrical energy storage technologies, lithium-ion batteries are presently used in most of the portable consumer devices such as mobile phones and laptops. They also feature a high power-to-weight ratio, excellent high-temperature performance, and minimal self-discharge. Although most lithium-ion battery components may be recycled, the expense of material recovery continues to be a problem for this sector.
• Nickel-Metal Hydride Batteries
Nickel-metal hydride batteries, which are often used in computers and medical equipment, provide significant specific energy and specific power. Nickel-metal hydride batteries have a significantly longer life cycle than lead-acid batteries, and they are also much safer and more resistant to abuse. Nickel-metal hydride batteries have several problems, including high cost, significant self-discharge and heat generation at high temperatures, and the requirement to regulate hydrogen loss.
• Lead-Acid Batteries
Lead-acid batteries may be engineered to be high power while being affordable, safe, and dependable. Their application is limited by their low specific energy, poor cold-temperature performance, and short calendar and cycle life.
Ultracapacitors store energy in a polarised liquid between an electrode and an electrolyte. As the surface area of a liquid rises, so does its energy storage capacity. Ultracapacitors can assist cars recover braking energy and give more power during acceleration and hill climbing. In terms of energy content, they can't currently compete with Lithium-ion batteries in the automobile industry, but their capacity is growing every year.