Battery Cell Manufacturing Safety 255

NFPA 704

A standard maintained by the NFPA that details a system of identification for the hazards of materials for emergency response. NFPA 704 labels typically meet OSHA's Hazard Communication Standard requirements and help first responders determine appropriate emergency response actions.

NFPA 70E

The standard for electrical safety in the workplace. <i>NFPA 70E</i> is used by OSHA to provide work safety guidelines for those working with electricity.

NFPA 855

A standard maintained by the NFPA that lays out minimum requirements for addressing risks associated with battery cells and other energy storage systems. NFPA 855 can apply to both stationary and mobile energy storage systems.

29 CFR 1910

The specific part under the 29th section of the Code of Federal Regulations titled Occupational Safety and Health Standards. 29 CFR 1910, Subpart E deals specifically with emergency planning and exit routes.

49 CFR 172.407

A specific part under the 49th section of the Code of Federal Regulations outlining hazard identification requirements for storing or transporting hazardous materials. Packages used for shipping battery cells and cell materials must comply with 49 CFR 172.407 labeling requirements.

AGVs

Automated guided vehicles. A programmable and highly sophisticated autonomous vehicle, often integrated with sensor technology, that moves throughout a space. AGVs are often used in warehouses and agricultural environments.

Anode

An electrode with a negative charge. In a battery, the anode sends current to the cathode.

Antistatic

Material that resists the flow of electricity. Antistatic material helps prevent operators from building up static charge or serving as a conduit for electricity.

antistatic wrist straps

A safety device worn around the wrist that conducts electricity away from the wearer and into the ground through a grounding cord attached to a grounded workstation. Antistatic wrist straps protect the technician and components from electrostatic discharge.

arc blast

The burst of light, heat, and pressure that accompanies arc flash. Arc blast exposure can cause serious physical injuries and permanent hearing and vision damage.

arc flash

An electrical explosion resulting from a short circuit that creates an electric arc between exposed conductors. Arc flash produces extreme heat and light and compromises the safety of employees who are exposed to it.

arc flash boundary

A border that defines the distance from an energized system at which an employee may experience second degree burns. Qualified employees must wear appropriate PPE to keep themselves safe when working inside an arc flash boundary.

arc-rated

Safety equipment that is designed to withstand high voltages. Arc-rated PPE reduces the risk of electrocution from arc flashes.

Automated guided vehicles

AGVs. A programmable and highly sophisticated autonomous vehicle, often integrated with sensor technology, that moves throughout a space. Automated guided vehicles are often used in warehouses and agricultural environments.

Automation

The use of self-regulated equipment, processes, or systems that meet manufacturing requirements with limited human intervention. Automation, which includes both robotic and computer numerical controlled (CNC) processes, is an efficient means of performing manufacturing processes.

Battery cell

A single unit of a battery. Battery cells contain a cathode, an anode, and an electrolyte solution.

Burrs

A rough edge on a metal part created by cutting or machining. Burrs on battery electrodes can pierce the separator and lead to short circuits.

busbar

Strips of copper or aluminum that create the main electrical connections between cells, modules, or other rechargeable battery components. Busbars used for grounding typically connect negative battery circuits to a chassis or other grounding source.

Calendering

The process of compressing dried electrode coatings with heavy rollers to create an even thickness and improve atomic structure. Calendering is the fifth major step in battery cell electrode manufacturing.

Can

A protective metal cover that surrounds some battery cells. Cans are typically cylindrical or prismatic and help prevent cell swelling, bending, and damage.

Carbon monoxide

A colorless, odorless, poisonous gas made of carbon and oxygen. Carbon monoxide may be emitted by Li-ion batteries that catch fire.

Cathode

An electrode with a positive charge. In a battery, the cathode receives current from the anode.

cell chemistry

The chemical composition that influences a battery's energy density, efficiency, cost, and lifecycle. Rechargeable batteries most commonly have lithium-ion, nickel-metal hydride, and lead-acid cell chemistries.

Charging

The process of restoring the chemical reactivity of a secondary cell battery. The charging cycle involves forcing DC back through the system.

chemical burns

An injury caused by contact with corrosive liquids or gasses. Chemical burns can range from minor to potentially fatal.

Chemical energy

A form of energy created by the reaction between two or more substances. Chemical energy is released by many substances, including gasoline and battery materials, and can cause burns.

chemical hazards

A substance or mixture of substances that is harmful to employees. Chemical hazards include substances in the form of liquids, vapors, fibers, or particles.

cleanrooms

An enclosed space in which contamination and variables like temperature, humidity, and air pressure are controlled and maintained. Cleanrooms are commonly used in industries like pharmaceuticals and electronics to ensure product safety and reliability.

Collaborative robots

Cobots. A robot that can be programmed to learn a specific task in order to assist humans. A collaborative robot is designed to interact with humans in a shared workspace.

Conveyor systems

A mechanical system consisting of a flexible belt and at least two fixed pulleys that is used to transmit motion. Conveyor systems should have their belts removed prior to maintenance work.

Cooling mechanisms

A device that removes heat from an electrical system in order to regulate temperature. Cooling mechanisms in battery packs work by circulating either air or liquid coolant.

Corrosive

Having the ability to erode or damage other materials. Corrosive substances can damage machine parts not rated to withstand them.

coveralls

Protective clothing that covers the entire body from the wrists to the ankles. Coveralls provide good general protection for the skin against hazards like skin irritants.

Crimping tools

A device used to pinch, bend, or press an object into the desired shape. Crimping tools might be needed to manipulate current collectors or electrode tabs in some instances.

current

The flow of electricity through a circuit. Stronger currents are more likely to cause serious injuries.

Current collectors

An exceedingly thin sheet of metal used to provide structure and conductivity to a battery cell electrode. Current collectors for lithium-ion battery cells are usually copper or aluminum.

Dendrites

A projection of metal that builds up on the surface of lithium. Dendrites are capable of penetrating the separator and crossing from one side of the battery cell to the other, causing short circuits.

Design controls

Any procedure or practice used during the design phase of a product to ensure quality and safety. Design controls are considered when developing battery cells that operate safely.

Die cutters

A tool used to cut and form a workpiece into the shape of a die. Die cutters may be automated or manually operated machines.

Discharging

The chemical reaction process of a battery. The discharging cycle is complete when a battery can no longer react to produce voltage.

dry rooms

A type of cleanroom that maintains lower humidity levels, typically below 1 percent. A dry room prevents ionic contamination in battery cell manufacturing.

electric shock

The flow of electricity through the body. Severe electric shock can be fatal.

Electric vehicles

EVs. A vehicle that is propelled by an electric motor that draws its power from a battery. Electric vehicles require high-energy, lightweight, rechargeable batteries.

Electrical energy

Energy created by the movement of electrons. Electrical energy can be converted into light, heat, or motion.

electrical fires

A fire involving energized electrical equipment. Electrical fires are very dangerous because they put employees at risk of electric shock in addition to burns.

electrical hazards

A circuit or electrical system component that is at risk of causing an electric shock to employees. Electrical hazards can be detected through arc flash hazard analyses.

electrical insulating gloves

Gloves typically made of rubber or other insulating material that prevent the flow of an electric circuit. Electrical insulating gloves are typically rated from Class 00 to Class 4.

electrode

A device within a circuit that conducts electricity. Electrodes in lithium-ion batteries consist of a graphite anode and a cathode made of a lithium compound.

electrode cutters

A tool or machine that cut electrodes into desired shapes using sharp edges. Electrode cutters pose the risk of lacerations or amputation.

electrode tabs

A small strip of uncoated current collector foil that enables electrodes to be welded to each other and to other components in the finished battery. Electrode tabs must be inspected to ensure they are free of spatter and meet weld specifications.

Electrolyte

A conductive liquid, gel, ceramic, or other solid containing an acid, an alkaline, or a salt. The electrolyte in a battery connects the two electrodes.

Engineering controls

A step taken by an operator or engineer to reduce hazards and safety risks. Engineering controls include choosing quality chemicals, installing exhaust systems, and maintaining machines and cutting fluid.

filling

A cell assembly step during which liquid electrolyte is added to the enclosed battery cell. Filling uses liquid injection machines to add pre-determined amounts of electrolyte to Li-ion batteries and other batteries that use liquid electrolytes.

fire blanket

A device made of fire-resistant materials that is placed over ignited materials to prevent oxygen from feeding and spreading the flames. Fire blankets may help slow or stop the spread of flames from ignited cells in an emergency until first responders arrive.

fire extinguishers

A portable device that uses a rapid spray of chemicals to put out small fires. The appropriate fire extinguisher type may vary depending on the type of fire present.

fire prevention plan

A proactive strategy that identifies procedures implemented to avoid fires in the workplace. Fire prevention plans include lists of major fire hazards and fire protection equipment needed to control these hazards.

fire-resistant

Made of materials that are designed to resist burning and withstand heat. Fire-resistant materials are essential to battery cell production safety.

first responders

A specially trained professional who is typically one of the first people to arrive and provide assistance in an emergency. First responders include firefighters, paramedics, and law enforcement officers.

fixtures

A custom workholding device that is designed to effectively support and hold a specific type of workpiece. Fixtures are used to transport cylindrical and prismatic cells and vary based on cell size and shape.

foils

An exceedingly thin sheet of metal. Foil wrappers are used to enclose pouch cell batteries.

fumes

Potentially hazardous gases and particulate matter generated at the electric arc during welding or cutting processes. Fumes include particulates from the electrode, flux, shielding gas, base metal, and any coatings included in a process.

General Duty Clause

A statement within the OSH Act that establishes that OSHA protections apply even to situations for which there are no specific standards. The General Duty Clause requires employers to furnish places of employment that are free from recognized health and safety hazards.

Grounding

A means of providing a safe path for electricity in case it strays from its intended path. Grounding substantially reduces the risk of electric shock.

Hazard Communication Standard

HCS. An established OSHA policy that sets guidelines for developing and disseminating information related to chemical safety in the workplace. The Hazard Communication Standard emphasizes the importance of labeling and providing safety data sheets, as well as proper training.

HCS

Hazard Communication Standard. An established OSHA policy that sets guidelines for developing and disseminating information related to chemical safety in the workplace. The HCS emphasizes the importance of labeling and providing safety data sheets, as well as proper training.

hydrogen fluoride

HF. A colorless gas that is extremely toxic and potentially fatal. Hydrogen fluoride gas is produced when a lithium-ion battery combusts or when ionic contamination causes water to interact with fluorine in the battery cell.

Industrial robots

A reprogrammable machine sometimes used in place of a person in a manufacturing setting. Industrial robots perform dangerous or repetitive tasks with a high degree of accuracy.

insulated

Covered in a material that prevents the passage of electricity. Insulated gloves, boots, and hard hats are common PPE for electrical work.

Insulation

Material that resists the flow of electricity. Insulation can prevent electric shock when used properly.

International Air Transport Association

IATA. An international organization that develops standards and guidelines for safe, efficient global airline travel and shipping practices. The International Air Transport Association has established strict guidelines for the transport of lithium-ion battery cells by aircraft.

International Electrotechnical Commission

IEC. An organization that governs electrical equipment standards in Europe and other countries outside the U.S. The International Electrotechnical Commission outlines the four measurement categories, or CAT designations, used to rate electrical testing equipment.

Ionic contamination

A type of battery cell contamination that results from unwanted moisture in the battery. Ionic contamination can cause a battery to generate hydrogen fluoride gas, which is dangerous to humans and the environment.

irritants

A chemical that causes inflammation and swelling in human tissue. An irritant usually causes short-term effects.

lacerations

A cut or tear in the skin. Lacerations can be caused by sharp objects or mechanical forces.

Li-ion

Lithium-ion. A type of rechargeable battery that uses a lithium compound as a cathode and, usually, graphite as an anode. Li-ion batteries are widely used in portable electronics and electric vehicles.

Lithium

A lightweight, silver-white metal that is highly reactive. Lithium is the most common element used in electric vehicle battery cathodes and electrolytes.

lithium-ion

Li-ion. A type of rechargeable battery that uses a lithium compound as a cathode and, usually, graphite as an anode. Lithium-ion batteries are widely used in portable electronics and electric vehicles.

Machine guards

A shield or covering over hazardous areas on a machine that prevents contact with body parts and prevents debris from exiting the machine. Machine guards often partially cover the point of operation while allowing necessary access.

mechanical hazards

A type of confined space hazard that exists when electrical or mechanical equipment may be accidentally activated. Mechanical hazards are one of three types of general confined space hazards.

Mechanical hazards

A type of confined space hazard that exists when electrical or mechanical equipment may be accidentally activated. Mechanical hazards are present with both automated and manual cell production equipment.

mixing

The process of combining and processing raw electrode materials to form slurry. Mixing is performed in ball mill or other mixing equipment.

National Fire Protection Association

NFPA. A non-profit organization that maintains standards of public safety and fire prevention. The National Fire Protection Association produces the standard for minimum safe electrical installations as well as arc flash prevention and safety procedures.

Occupational Safety and Health Administration

OSHA. A government agency under the U.S. Department of Labor that sets the standards for working conditions in the United States. The Occupational Safety and Health Administration ensures that employees work in safe and healthy environments.

OCV

Open circuit voltage. The amount of energy, in volts, that is currently available in a battery that is not connected to a load or charger. OCV readings help determine a battery's self-discharge rate, state of charge, and state of health.

open circuit voltage

OCV. The amount of energy, in volts, that is currently available in a battery that is not connected to a load or charger. Open circuit voltage readings help determine a battery's self-discharge rate, state of charge, and state of health.

OSHA

Occupational Safety and Health Administration. A government agency under the U.S. Department of Labor that sets the standards for working conditions in the United States. OSHA ensures that employees work in safe and healthy environments.

particulate matter

A solid contaminant that can alter the quality of sensitive battery cell components. Particulate matter includes particles of metal, dirt, and sand.

Personal protective equipment

PPE. Any clothing or device used to minimize exposure to hazards and prevent injury. Personal protective equipment includes safety glasses, gloves, masks, coveralls, and earplugs.

Pick-and-place

The process of moving parts from one location to another. Pick-and-place robots, sometimes called part-transfer robots, improve the precision, quality, and speed of manufacturing operations.

Pinch points

Any place where two moving components come together. Pinch points can cause injury if a body part comes into contact with the area.

Pliers

A pincer-shaped tool with flat gripping surfaces used to hold objects or bend wire. Pliers might be needed to handle electrode tabs or other battery cell components.

PPE

Personal protective equipment. Any clothing or device used to minimize exposure to hazards and prevent injury. PPE includes safety glasses, gloves, masks, coveralls, and earplugs.

Raw materials

An unprocessed material that has not yet been manufactured. All battery cells require the collection and processing of raw materials.

reactive

Having a tendency to react chemically. Reactive metals are the negative electrodes in battery cells.

Respirators

A breathing device worn to prevent inhalation of hazardous substances. Respirators may purify air or supply clean air for the wearer.

respiratory

Concerning the organs involved in breathing air. Respiratory organs include the nose, larynx, and lungs.

Safety data sheets

SDS. Mandatory information that must accompany almost every chemical in the workplace except for items like cleaning supplies. A safety data sheet includes details such as the hazards, precautions, and first-aid procedures associated with the chemical.

sealing

The process during canning in which a battery cell is welded shut. Sealing methods are used during the canning process of pouch cells, prismatic cells, and cylindrical cells.

Self-discharge

The capacity loss that batteries experience during storage. Self-discharge occurs because of internal leakage between a battery's electrodes.

Self-discharge rate

The amount of energy a battery loses over a specific amount of time when it is not connected to a circuit. Self-discharge rates increase when batteries have defects.

Sensors

A device that detects the presence or absence of an object, or certain properties of that object, and provides feedback. Common sensor applications include detecting, counting, positioning, and diverting parts on a production line and preventing the unsafe operation of a machine.

separator

A film in a battery cell that provides a barrier between the anode and cathode. Separators allow ions to pass through when the battery is charging or discharging but prevent the flow of ions when the battery is not in use.

Shelf life

The length of time a battery can remain in storage without losing capacity. Shelf life is determined by the battery's rate of self-discharge.

Short circuits

A condition that occurs when current takes a shorter, unintended path between two conductors, interrupting the intended flow of electricity. Short circuits cause excess current flow, which can destroy electronic components and cause fires and shock.

Slitting

An electrode cutting process that separates large rolls of electrode sheets into smaller rolls that are easier to machine and handle. Slitting divides large mother rolls into several smaller daughter rolls.

slurry

A mixture of liquid and suspended solids. Slurries for electrode manufacturing contain a blend of active materials, inactive materials, and solvents.

SoC

State of charge. The amount of energy, given as a percentage, that is currently contained in a battery. SoC must be monitored in Li-ion batteries to prevent over and undercharging and to promote cell balancing.

state of charge

SoC. The amount of energy, given as a percentage, that is currently contained in a battery. State of charge must be monitored in Li-ion batteries to prevent over and undercharging and to promote cell balancing.

static electricity

An electrical charge caused by the buildup of friction in a person or object. Static electricity can be controlled through the use of machine grounding or using safety accessories, such as antistatic mats.

Sulfur

S. A pale, yellow, brittle element. Sulfur is an abundant, inexpensive element, which helps reduce battery production costs when it is used.

Sulfuric acid

A highly corrosive, oily acid made of sulfur, oxygen, and hydrogen. Sulfuric acid is used as the electrolyte in lead-acid batteries.

thermal conductivity

A physical property that indicates how well heat energy transfers through a material. Thermal conductivity depends on the material's structure and temperature.

thermal hazards

A condition, object, or substance that produces dangerously high or extreme temperatures. Thermal hazards can pose the risk of potential fires or explosions.

thermal imager

A thermal inspection device that uses infrared technology to produce a visual representation of temperature conditions. Thermal imagers are also called infrared cameras.

Thermal interface materials

TIMs. Any material that dissipates or conducts heat between two or more contacting surfaces. Thermal interface materials in battery packs include cushions, adhesives, seals, and other components.

Thermal runaway

The process of a defective or damaged battery cell overheating and damaging nearby cells, causing them to also overheat. Thermal runaway can cause fires or explosions.

Thermal stability

The ability of a material to resist changes in physical shape or size as its temperature changes. Batteries with low thermal stability can malfunction or catch fire as their materials warp at high temperatures.

traction rollers

A rotating mechanical device that rolls out finished electrodes or other materials in a flat orientation for further processing. Traction rollers can potentially pull objects into the machine.

Tweezers

A forceps like device used for grasping small objects. Tweezers can be used for placing or holding small electronic devices.

UN 38.3

A United Nations (UN) standard outlining a series of eight tests that battery cells must pass before they can be considered safe for shipping. UN 38.3 testing is required by the International Air Transport Association (IATA) for all lithium-ion batteries prior to air transport.

Ventilation

A means of providing fresh air. For the safety of workers, welding and cutting processes require proper ventilation.

Volts

V. A unit of measurement that indicates the amount of electrical force or pressure in a circuit. Volts measure voltage, which is also known as electromotive force.

Welding

A joining process that permanently bonds together two separate components with heat, pressure, or a combination. Welding is often performed by robots in manufacturing facilities.

winding

The process of layering electrodes and separators to create a stack or roll that matches the size and shape of the finished battery cell. Winding may also be called rolling, stacking, folding, or other terms, depending on the cell geometry and processes used.

Work envelopes

The defined area through which a robot can move. The work envelope, or work cell, is generally enclosed by a cage or guard fence and defines the area that operators should remain outside in order to be safe during active production.