Beyond the Charge: Managing Lithium-Ion Battery Risks

Lithium-ion batteries provide rechargeable energy sources that are becoming the industry standard due to portability, lightweight designs, fast charging, and high-density energy capacities. As their use has expanded, so has a largely hidden exposure that many organizations may not fully appreciate or recognize. Lithium-ion batteries used in items like electric vehicles, power tools, lawncare equipment, and even laptops, can become overheated when the battery experiences conditions like extreme heat, overcharging, a puncture, or a defect. While the likelihood of a battery-related incident may seem uncommon, the severity of failure can be significant.

“There are several straightforward practices that can prevent the chain reaction thermal runaways we have seen in the field related to lithium-ion batteries,” said Sonya Luisoni, Senior Risk Control Manager at Safety National. “Preventing these incidents starts with understanding which batteries are onsite, who uses them, where they are charged and stored, and whether employees know the warning signs, including the importance of state of charge.”

Recognizing Lithium-Ion Battery Hazards

While there are benefits for the use of these batteries in several industries, there are also a handful of risks associated with these devices, including:

• High energy density in a small package.
• Rapid heat generation.
• Thermal runaways that can escalate fast, sometimes resulting in explosions.
• Fire that can spread from cell to cell.
• Reignition that can happen hours or days later.
• Toxic/flammable gas release.

Early warning signs of battery failure can include excessive heat, swelling, hissing sounds, smoke or vapor, and a strong chemical odor. If any of these signs are present, stop using the equipment, isolate it if safe to do so, and follow emergency procedures.

Safe Charging Practices

Lithium-ion batteries are embedded across countless industries, powering a multitude of devices such as bikes, phones, vehicles, medical equipment, power tools, and more. With a wide range of battery powered devices, it is important for organizations to emphasize safe charging practices to reduce the risk of thermal runaway and equipment failure, which include:

1. Using manufacturer-approved chargers and charging stations only.
2. Enforcing prohibited practices (use of extension cords, damaged cables).
3. Monitoring during charging.
4. Training on how to respond if a charger faults or overheats.
5. Keeping charge stations clear of combustibles.

Storage and Handling Procedures

Proper storage and handling further reduces risk, especially in the event of failure. Clear, established protocols are essential, such as the following:

1. Follow state-of-charge (SOC) guidelines during storage.
2. Use designated battery storage areas that are cool and dry, protected from physical damage and away from heat sources or direct sunlight.
3. Maintain appropriate spacing between battery-powered equipment.
4. Safely isolate and manage damaged or suspect batteries.
5. Avoid stacking battery-powered devices unless using approved systems.

Why State of Charge Matters

State of charge refers to the battery’s remaining charge relative to its full capacity, usually expressed as a percentage of its total usable capacity. SOC is important for the safe storage of lithium-ion batteries because the amount of energy stored in the battery directly affects the severity of a potential failure event. Many manufacturers and safety standards recommend storing lithium-ion batteries at a partial charge, often around 30–50% SOC, because it balances safety, battery longevity, and readiness for use.