A Li-ion battery or lithium-ion battery is a rechargeable in which lithium ions are essential during charging or discharging. They are the batteries that are used in most modern electric vehicles and portable electronics such as laptops, mobile phones, watches, among others. Their application is also becoming popular in aerospace and military technologies.
In Li-Ion chargeable batteries, current flow from the positive electrode to the negative electrode through an electrolyte when charging and back when discharging. At the negative electrode, typically graphite materials are used while intercalated compounds of lithium are used at the positive electrode. This way, Lithium-ion batteries can hold a high energy density while at the same time achieving a low discharge capacity. Also, other than the LFP cells, these batteries have no memory effect.
The performance of Lithium-ion batteries varies according to their positive and negative electrodes. However, most of them have a specific energy density in the range of between 360 to 900 kJ/kg and a volumetric power density between 900 to 2230 J/cm3. Other factors affecting performance, such as internal resistance, is independent of the cycling and age of the battery. Old and more cycled batteries have a high internal resistance, which may negatively affect their performance. Whenever there is high internal resistance in cells, the voltage in both the positive and negative terminals drop when loaded and then decrease the minimum energy draw. This way, the standard functionality of the battery is affected and, in most cases, will result in devices overheating or a drop in voltage.
The performance of most lithium-ion batteries has improved over time. They have grown in energy density, energy capacity, and charging properties. For instance, unlike some times back when they needed two or more hours to full charge, today, lithium-ion batteries can be fast-charged. When charged using a compatible fast charger, most of these batteries will be fully charged in less than an hour.
In conventional terms, battery life, also termed as life cycle, can be described as the full charge-discharge cycles a battery may undergo to reach a threshold of failure measured in terms of impedance rise or capacity loss. Capacity loss incorporates inactive storage capacity of a cell, and if it cannot store energy for long, its life span may be considered short.
Numerous factors affect battery life. For instance, subjection it to stress factors such as temperature, depth of discharge, charge current, discharge current, among others. However, the measure of battery life using the charge, discharge cycle is often termed misleading, especially in time applications such as in smartphones, laptops, and electric vehicles. To bring efficiency, most manufacturers and researchers in the industry promote the use of cumulative discharge during the entire life cycle of a battery to determine its life. However, it is essential to note that battery life and performance are likely to deteriorate with time, mainly due to degradation, conditioning, multicellular devices, etc.
Due to their ability to hold a high energy density, Lithium-ion batteries are used as the energy source for numerous devices in diverse fields. They are electric batteries in electric vehicles such as electric bicycles, hybrid vehicles, scooters, electric motorbikes, and other select types of transporters. In developed instances, they are being applied to electric power wheelchairs, aircraft, radio-controlled devices, among others.
Other than its usage in electric vehicles and transporters, Li-Ion batteries are widely used in portable devices and other particular purpose tools. They are the source of power for devices such as laptops, smartphones, digital cameras, tablets, electronic cigarettes, camcorders, and handheld game tools e.g., pads. Also, in equipment such as sanders, cordless drills, saws, and other farm tools, Li-ion batteries serve as the primary source of power for them.
Li-ion chargeable batteries are environmentally friendly. These batteries are made of components such as iron, cobalt, nickel, and copper, which are categorized as safe for the environment. Also, unlike most other batteries, li-ion batteries are non-toxic as they do not contain cadmium or lead. Other than being less toxic, lithium-ion batteries contain elements that are easy to recycle, and due to their environmental impact, these batteries are highly recommended by naturalists and several other parties with a concern for the environment.