Lithium-ion batteries were invented in 1980 by John Goodenough; they were commercialized in 1991 by Sony. In the past decade, lithium-ion batteries have become the dominant rechargeable battery chemistry in nearly all industries. Lithium-ion, in comparison to previous popular chemistries, (Lead acid, Nickel-Cadmium, and Alkaline) is better in many ways. With the advancement in technology, a battery that is safe and powerful is in great need. Lithium is the most energy dense chemistry in use and with added features, can be the safest. Lithium energy is an active area of study, so new chemistries are being developed every year.
Anode: The anode is the negative electrode in the cell. It is very common, in lithium-ion batteries, for it to be composed of lithium and carbon, usually a graphite powder. The current can be collected due to the copper film that is combined with the electrode. The purity, particle size, and uniformity of the anode all contribute to the aging behavior and capacity.
Cathode: The cathode is the positive electrode. This is where all the different chemistries come into play. The cathode is what determines the overall lithium chemistry. Like the anode, a current collector is combined with the material so the flow of electrons can occur. The cathode is typically combined with an aluminum film. As shown above there are many different chemistries. The key differences between them is temperature at which they react with the electrolyte (thermal runaway) and the voltages they produce.
Electrolyte: The electrolyte allows the transfer of the lithium ions between the plates. Typically, it is composed of different organic carbonates, such as ethylene, carbonate, and diethyl carbonate. The different mixtures and ratios vary depending on the application of the cell. For example, for a low temperature application the electrolyte solution will have a lower viscosity compared to one made for a room temperature environment. Lithium salts are essential in the mixture of the electrolyte, the salt determines the conductivity of the solution as well as aids in the formation of the solid electrolyte interface (SEI). In lithium batteries, lithium hexafluorophosphate (LiPF6) is the most common lithium salt. LiPF6 can produce hydrofluoric acid (HF) when mixed with water. The SEI is a chemical reaction between the lithium metal and electrolyte. Under normal conditions the cell manufacturer typically slow charges the cell to form an even SEI on the carbon anode.
Separator: Lithium-ion cell separators are porous plastic films that prevent direct contact of the anode and cathode. The films are usually 20 μm thick and have small pours that allow lithium ions to pass through during the charge and discharge process. A “shutdown” separator is the most common. This separator will close the pores to prevent lithium ions to pass through, once the cell is out of the temperature range or a short occurs. Separators continue to be developed today to improve safety, while also increasing the capacity of the cells.
UL Listed/Certification: Underwriters Laboratories (UL) Listed/Certification means that UL has evaluated samples of products to ensure that they meet specific requirements. This includes testing samples that cover functional safety and use cases.
Internal Combustion Forklift: A forklift with an engine that uses fuel to run. The fuel is burned within the engine which produces power directly to the forklift. Fuel is typically gasoline, diesel, liquified petroleum gas, or compressed natural gas.
Opportunity Charging: The practice of using natural periods of downtime, like operator meal breaks, to charge the battery for short periods of time throughout the day. This allows operators the continuous use of the same battery throughout multiple shifts.
Equalization Charging: Overcharging the battery after a full charging cycle at a higher-than-normal voltage. This step is necessary help remove built-up sulfate and balance the voltage of each cell in lead acid batteries.
Battery Degradation: The process that reduces the amount of energy a battery can store. Temperature, charge, and discharge voltage, current and the depth of charge and discharge can affect how much a battery’s capacity is reduced over time.
Battery Lifespan: How long a battery can operate during its life. Lifespan is measured by the number of completed charge and discharge.
Battery Cycle Count: The cumulative number of charges and discharges if the battery completes one charge and discharge as a cycle. The battery cycle is comprised of 100% discharge and charge.
Battery Operating Temperature: The acceptable temperature of the surrounding environment at which a battery operates. The battery may fail if the operating temperature is outside of the range.
TPPL Battery: Thin Plate Pure Lead (TPPL) batteries are a type of lead acid battery which have electrodes that are thinner than traditional lead acid battery designs. TPPL batteries have a high rate of charge and discharge which increases the level of internal heat. This causes the life of a TPPL battery to deplete faster than other types of lead acid batteries.
AGM Battery: Absorbent Glass Mat (AGM) batteries are a type of lead acid battery which contain a glass mat separator. This separator absorbs the electrolyte solution between the battery plates like a sponge which keeps the battery water levels down so you don’t have to water them as constant as other lead acid batteries. However, if the battery is overcharged, gas pressure builds within the cell and will cause the battery to dry out and fail.
Battery Energy Density: The measure of how much energy a battery contains in proportion to its weight. This measurement is typically presented in Watt-hours per kilogram (Wh/kg). A watt-hour is a measure of electrical energy that is equivalent to the consumption of one watt for one hour.
Flooded: A flooded battery has plates, separators, and a high-density paste material. It uses a liquid electrolyte that submerges the plates. The liquid solution can be damaged in extreme temperatures due to evaporation or freezing. This requires watering and maintenance of the battery.
Battery Discharge Rate: The amount of current divided by the time it takes to discharge a battery. It is defined as the stable current in amperes (A) that is taken from a battery of specified capacity (Ah) over a period of time.
Battery Charge Rate: The amount of current divided by time it takes to charge a battery. It is the amount of charge added to the battery per unit time.
C-rating: The rate of time it takes to charge or discharge a battery. C-rating is another way of representing the charge or discharge rates, where 1C is equivalent to charging or discharging the entire capacity of the battery in one hour.
Battery Efficiency: The amount of energy that a battery delivers compared to the amount of energy that is put into it during charging. Factors that affect battery efficiency include charge current, internal resistance, battery temperature, and battery age.
Battery Overcharging: Overcharging a battery is charging a battery more than its designed capacity. This can create unstable conditions inside the battery, increase pressure, and cause thermal runaway. This can be damaging to the battery, the equipment, and the operator.
Battery Regulator: A battery regulator limits or controls the rate at which current is added to or drawn from batteries. This keeps the voltage in a circuit relatively close to the desired value of the battery.
Ergonomic Risk: Situations that may present risks to people. These include any physical wear and tear on the body or injury related accidents.
UL Recognized: UL Recognized does not apply approval for complete products. Instead, it focuses on components and parts that are used within other products. It certifies that a component within a larger mechanism meets UL standards. UL Recognized is easier to attain than UL Listed.
Class 1 Forklift: Also known as electric motor ride forklifts, Class 1 forklifts can be stand up or sit-down models. These forklifts can include counterbalanced or three-wheel trucks. These forklifts can handle a capacity of 8,000 lbs. or more, making them essential when lifting heavy materials throughout a facility.
Class 2 Forklift: These forklifts are used for multiple applications and can include order pickers, turret trucks, narrow aisle forklifts and more. Many of these forklifts are designed to operate in tight spaces and narrow aisles.
Class 3 Forklift: These forklifts include pallet jacks, walkie stackers, end riders and center riders. Class 3 forklifts are designed to lift loads a few inches off the ground for transportation. They have minimal lift capabilities (i.e. lifting a pallet off the ground) used to transport materials throughout a facility.
Current Rating: The maximum current that a fuse will hold for an amount of time without degrading the fuse.
Thermal Stability: Stability of a fluid and its ability to resist breaking down under heat stress. If the heat reaches max temperatures, the fluid will deteriorate.
SEI Film: SEI film (solid electrolyte interphase) is a layer that is formed from the decomposition or breaking up of the electrolyte of the battery. This is important for lithium-ion batteries because it affects the cycle life.
Internal Resistance: Internal resistance is the resistance in a battery which causes a drop in the source voltage when there is a current. Internal resistance restricts the voltage delivery and determines the battery’s runtime.
Battery Management System: The brain of the battery pack. It manages the operation of a battery pack. The BMS also allow users to monitor cells within a battery pack. It can provide the status and health of a battery.
Forklift Telematics Systems: Forklift tracking devices that send, receive, and store data on one forklift or up to an entire fleet of forklifts. This lets users monitor forklifts to make operative decisions.
Industry 4.0: The fourth industrial revolution. It is the automation of conventional manufacturing and industrial applications. Industry 4.0 will use modern smart technologies including artificial intelligence (AI), robotics, Internet of Things (IoT), genetic engineering, quantum computing, and others.
Industrial Internet of Things: The interconnected sensors, instruments, and other devices connected together with computers’ industrial applications, including manufacturing and energy management. In use cases, smart devices may be deployed in vehicles, robotics, power systems, and more.
Cell Balancing: The equalization of voltages and state of charge among the cells within a battery when they are at full charge. This is a practice that preserves the capacity of a battery pack with multiple cells.
Battery State of Health: This refers to the battery’s life and reflects the ability of a battery to deliver and receive charge. The SOH is the comparison of a battery’s releasable capacity compared to the capacity of an identical new battery.
Cathode Electrolyte Oxidation: The electrochemical reaction that occurs in the cell of a battery. The cathode oxidizes the electrode which acquires electrons from the circuit and the cathode is reduced during the electrochemical reaction. The electrolyte acts as a medium that provides the ion transport mechanism between the cathode and anode.
Thermal Runaway: When heat generated in a battery exceeds the amount of heat that is dissipated to its surroundings. In batteries this occurs when a cell exceeds a specific high temperature which varies by chemical composition, because of thermal failure, mechanical failure, short circuiting, and electrochemical abuse.
Equivalent State of Charge: The level of charge for a battery related to its capacity. The SOC determines the remaining capacity and energy available in a battery pack.
Predictive Maintenance: Using data to analyze the condition of equipment and forecast when maintenance is needed.
Airport Ramp Equipment: Used for the loading and unloading of cargo and passenger bags in airports. It is also used to transport baggage, mail, and other cargo to and from the airport terminal and plane.
Ground Support Equipment: The support equipment used at an airport to provide service. This includes refueling, towing airplanes, towing luggage, loading luggage, transporting passengers, and other airport services.
Electric GSE: Electrical equipment that is used at an airport to service airplanes between flights. Electric GSE offers benefits such as energy efficiency, zero emissions, and others.
Battery Cooldown Period: Batteries produce a considerable amount of heat when charging, so they require a battery cooldown period. This allows the battery temperature to decrease after charging for a prolonged amount of time.
Ideal Temperature Range: All batteries have defined operating temperature to maximize their lifespan and ensure safety. Lithium-ion batteries should be charged within a range of 32°F to 131°F, and discharged between -4°F to 131°F.
Voluntary Airport Low Emissions Infrastructure Program: The Voluntary
Airport Low Emissions Infrastructure Program (VALE) is a national program designed to reduce sources of airport ground support emissions. This program improves current airport air quality.
Voluntary Airport Zero Emissions Vehicle Infrastructure Program: A program that facilitates the use of zero emissions technologies to improve airport air quality. The program allows airport sponsors to use funds to buy zero emissions vehicles and to build or improve infrastructure which is necessary to use zero emissions vehicles.
AGV: Automated guided vehicles (AGV) are vehicles designed to perform material handling or load carrying without the use of an operator or driver. AGVs are guided by sensors, markers, tape, or wires in the facility and have a fixed navigational route.
AMR: Autonomous mobile robots (AMR) are more technologically advanced than AGVs. They move around the facility based on the most efficient path using sensors and cameras. AMRs can navigate around obstacles, adapt to its surroundings, and avoid anything in their way.
Warehouse Automation: The process of automating warehouse activities with minimum human assistance. Warehouse Automation solutions include automated storage retrieval systems (AS/RS), automated guided vehicles, Autonomous mobile robots, automated sortation systems, picking systems, and more.