Understanding hazards and safety risks from use and storage
By Brianna Boyd, CHES, MPH (c), Derek G. Shendell, D.Env., MPH and Koshy Koshy, Ph.D.
Historical background
The rechargeable battery was invented in 1859, but the first Lithium-ion batteries (LIBs) became commercially available in 1991. LIBs have become the most popular battery, powering everything from smartphones and laptops to electric vehicles. LIBs are preferred for many applications because of their high density, long cycle life and low self-discharge rate. In 2019, John B. Goodenough, M. Stanley Whittingham and Akira Yoshino received the Nobel Prize in Chemistry for their contributions to developing modern LIBs.
Introduction to present issues for NJ K-12 schools
Despite their widespread use and numerous advantages, LIBs pose significant hazards. LIBs are prone to overheating, fires and explosions, which can have consequences for safety and health, especially in environments such as schools where both students and adults spend much time daily and use electronic rechargeable devices frequently. The U.S. Consumer Product Safety Commission (CPSC) reported at least 25,000 incidents of fire or overheating in lithium-ion batteries over a recent five-year period (CPSC, 2018). Overcharging, physical damage and manufacturing defects can trigger thermal runaway, one of the most prevalent concerns.
Therefore, properly educating school administrators, educational support staff, students and teachers about the safe use, charging, storing and recycling of lithium-ion products is critical to helping reduce the threat of unwanted injuries due to burns upon contact with temperature extremes, explosions and other hazards.
Safety and health risks
The health risks associated with end users and LIBs are extensive. Concerns include fires, explosions, toxic gas emissions, electrical hazards and chemical exposure. A well-documented safety concern is thermal runaway, a rapid self-heating process driven by internal exothermic reactions. In simpler terms, a thermal runaway is like a chain reaction inside the battery. It can be triggered by battery integrity disruption, internal failure, or overheating/overcharging, potentially leading to fires or explosions, and causing serious injuries.
A mixture of flammable, toxic and corrosive volatiles may be released during a thermal event. In confined spaces, such as a small classroom or internal storage closet, any release of solvents or gases poses a direct risk to teachers and students. To avoid chemical exposure, staff and students should not disassemble devices as direct contact with the battery’s internal materials can cause respiratory issues, skin irritation and other health problems.
Schools must be informed about the proper disposal of equipment with LIBs that have expired or can no longer be recharged. Improper disposal can result in a fire or explosion in confined spaces, such as trash cans, or during transport to landfills. Ideally, dead and/or expired LIBs would be disposed of at an approved e-waste recycler. However, 95% of LIBs end up in the landfill system, posing a direct threat to public health as these types of batteries may leach potentially toxic metals into the groundwater.
Proper storage
Proper storage of LIBs prevents reduced battery performance, physical damage and financial loss. When storing LIBs, one should consider temperature, humidity, ventilation, fire safety and accessibility. Temperature is the most critical factor, as temperature extremes, both hot and cold, can harm battery performance and safety.
End users should ensure any electronic devices containing LIBs, regardless of size, are not exposed to temperatures below 32°F (0°C) or above 80°F (28°C). Storing LIBs in a cool, dry place with temperatures between 59°F to 77°F (15°C to 25°C) is ideal. High temperatures should be avoided as they may accelerate the thermal runaway process.
Extreme heat and direct sunlight can degrade the batteries and increase the fire risk. Similarly, extreme cold temperatures can increase internal resistance and cause irreversible damage, resulting in battery failure. Areas that experience harsher winters should consider temperature-controlled storage solutions. If a device has been exposed to cold temperatures, it is recommended for the device to be allowed to gradually return to room temperature before use.
In addition to temperature and humidity, moisture levels can impact the performance and safety of LIBs. Most storage areas used for LIBs likely have neither humidity control nor enhanced, appropriate ventilation. Excessive moisture can lead to corrosion, increasing the risk of leaks and short circuits. For devices stored inside, dry storage environments are recommended. Maintaining humidity levels below 80% and ensuring good ventilation can prevent moisture-related damage and the buildup of harmful gases.
Moreover, it is crucial to follow manufacturer guidelines, including those for storage, handling and charging. Use only approved charging solutions for your devices. In a school setting, where a wide range of devices are used, implementing a battery management system (BMS) device is highly recommended. A BMS can monitor battery life, temperature and other key parameters.
Fire safety is also a significant concern when storing LIBs, which should be kept away from flammable materials and potential ignition sources. Regularly inspecting and monitoring the storage area can help identify potential hazards early and mitigate risks.
By adhering to these guidelines, the risk of harm can significantly be reduced, and the lifespan of the LIBs can be extended. Proper storage safeguards the school’s investment and can ensure classroom safety. By considering factors such as temperature, humidity and safe storage practices, schools can ensure that their LIB devices perform optimally, and classrooms remain safe from injuries due to improper storage.
Brianna Boyd is a certified health education specialist currently pursuing an MPH in Occupational Health and Safety at the Rutgers School of Public Health at the Rutgers School of Public Health, where Dr. Derek Shendell is a professor and Dr. Koshy Koshy is an associate professor. They worked in coordination with the New Jersey Work Environment Council to produce this article.
What schools can do
Lithium-ion batteries (LIBs) have revolutionized how devices are powered, offering numerous advantages. However, their widespread use brings significant safety and health concerns. It is essential that schools follow take the steps below.
- Educate end users about the safe use, storage and disposal of LIBs is essential to reducing injuries and accidents.
- Invest in safety features. Pressure vents, thermal cutoffs and advanced battery management systems can help prevent overheating and thermal runaway.
- Follow all current state and federal regulatory standards. Adhering to such guidelines will help reduce the risk of incidents at the manufacturing, transportation, and disposal or recycling levels to help minimize the risk of fires and reduce environmental impacts.
Ongoing research and development are necessary to improve battery design and materials, ensuring safer, more efficient LIBs in the future.
References and resources
Australian Competition and Consumer Commission
“Lithium-ion Batteries and Consumer Product Safety” (2023)
Occupational Safety and Health Administration U.S. Department of Labor
U.S. Consumer Product Safety Commission
“Status report on high energy density batteries project” (2018)