Lithium-based Battery Safety

Lithium-based batteries differ from other battery types (e.g., alkaline, lead acid) in that they store a much greater amount of energy in a small amount of space.

• Lithium batteries are “single use.” These non-rechargeable (primary cell) batteries have a longer shelf life than lithium-ion per charge and have a lower upfront cost.
• Lithium-ion (Li-ion) batteries are rechargeable (secondary cell). The ability to recharge them for many cycles makes them more cost effective than single use lithium batteries over time. Li-ion batteries use a liquid electrolyte (an electrically conductive material).
• Lithium polymer (LiPo) batteries are also rechargeable but can hold more stored energy in a much lighter-weight package than Li-ion batteries by using a semisolid (gel) polymer electrolyte.

In its simplest sense, a cell is a single primary or secondary battery (e.g., AA, AAA). When multiple cells of the same type are connected to work together, they are called battery packs.

Lithium-based batteries, rechargeable or not, have high energy densities, or the ability to store a much greater amount of energy in a small amount of space. Damaged lithium batteries can enter an uncontrollable self-heating process known as thermal runaway, which may happen during charging, use or storage under certain conditions.

Thermal runaway may cause a fire and explosion. In either case, there is a lot of stored energy available to sustain the process, more than other battery types (alkaline, lead acid, etc.). Additionally, lithium batteries create oxygen as they burn, making it more difficult to interrupt the burning process which further intensifies the heat, accelerates thermal runaway and increases damage to people, property and the environment.

There are many situations that can lead to battery damage, some more pronounced than others. Take care to protect your batteries and devices from any of these situations.

• Over-charging or discharging. Lithium batteries are best kept between 20% - 80% of their charge capacity. Both a full charge and a full discharge can reduce the lifespan and overall capacity of the battery.
• Unbalanced cells. Using mismatched cells can cause excessive cell wear and degradation and reduces the lifespan of the entire battery. When replacing batteries in devices that use more than one, be sure they are all fresh, identical batteries to help avoid this problem.
• Excessive current discharge. A battery that discharges faster than its rated capacity may overheat and be physically damaged.
• Short circuits or poor electrical connections. Both situations may cause overheating and physical damage.
• Physical damage. Dropping, crushing or puncturing a lithium battery or exposing it to temperature extremes (roughly, below freezing or above 130 degrees Fahrenheit), can cause damage to the internal structure and potentially trigger thermal runaway.
• Improper storage.

See also: Q12, Can I store Li-ion batteries?

According to the US Occupational Safety and Health Administration (OSHA), signs of damage include:

• Bulging
• Cracking
• Hissing
• Leaking
• Abnormal odors
• Rising temperature
• Smoking

Always inspect batteries for any signs of damage before use. Any battery that is known or suspected to be damaged must be taken out of service. Contact EHS at 208-885-6524 promptly to arrange for proper disposal.

Dispose of used lithium batteries by contacting EHS directly (208-885-6524). You may be asked to complete an online Chemical Waste Collection Form, but start with a phone call so we can respond quickly. EHS staff will arrange to collect the batteries. Never send lithium batteries to Surplus, through Campus Mail or place them in regular trash.

Although EHS can only take batteries used by the university, we still want to know about any damaged lithium batteries on campus.

If batteries are showing evidence of thermal runaway failure, or if there is any other indication of immediate danger to life, property or the environment, call 911 and notify EHS at 208-885-6524. Outside of regular business hours, call 911 and notify Campus Security at 208-885-7054.

ONLY if it is safe to do so, follow these steps if there is evidence of a battery malfunction (e.g., swelling, heating, abnormal odors):

• Use personal protective equipment, such as gloves, goggles/safety glasses and a lab coat.

• Use extreme caution because the emitted gases may be flammable and toxic.

• Disconnect the battery from its power source/charger.

• Remove the battery from the equipment/device.

• Place the battery in a metal container away from combustibles. Ceramic pots or cinderblocks may also work as emergency containers. Fill the container with sand or kitty litter if readily available.

• Contact EHS at 208-885-6524 for assistance. Outside of regular business hours, call the fire department (911) and Campus Security (208-885-7054).

No. Given the fire hazards that come with lithium-ion batteries, these items are not allowed in university buildings. The batteries on these devices are much larger than those in cell phones, laptops, and similar devices, and can store substantially more energy. If a battery malfunction occurs, the larger batteries will be able to burn longer and have a much higher potential for personal injury and property damage.

Because there are many variables that lead to lithium-ion battery failures, and the safety of any individual battery cannot be ensured, hover boards, e-bikes, e-scooters and other similar devices are not allowed in university buildings.

See also: Q4, How might lithium batteries become damaged?

If you are using these batteries, you should:

• Always purchase batteries from a reputable manufacturer or supplier.
• Read all documentation supplied with your battery.
• Never burn, overheat, disassemble, short-circuit, solder, puncture, crush or otherwise damage battery packs or cells.
• Do not put batteries in contact with conductive materials, including water, seawater, strong oxidizers or strong acids.
• Avoid excessively hot and humid conditions, especially when batteries are fully charged.
• Do not place batteries in direct sunlight, on hot surfaces or in hot locations.
• Do not store batteries at low or freezing temperatures.
• Immediately disconnect the batteries if, during operation or charging, they emit an unusual smell, generate heat, change shape/geometry or behave abnormally.
• Contact EHS for disposal; do not send to Surplus, send through Campus Mail or place in regular trash.

See also: Q10, Are there safe battery charging protocols?

Yes, the National Fire Prevention Association (NFPA) and battery manufacturers have common charging recommendations. Here are some general recommendations:

• If a battery will not take a charge, something is likely wrong with the battery. Remove it from the charger and contact EHS.

• Always use the charger that came with the battery and follow manufacturer’s instructions.

• Never charge a disposable (lithium or alkaline) battery; store one-time use batteries separately.

• Charge or discharge the battery to approximately 50% of capacity before long-term storage.

• Use chargers and methods designed for lithium batteries and their specific charge profile.

• Disconnect batteries immediately if, during operation or charging, they emit an unusual smell, develop heat, change shape/geometry or behave abnormally. Contact EHS for proper disposal.

• Remove cells and packs from chargers promptly after charging is complete. Do not use the charger as a storage location.

• Charge and store batteries in a fireproof container and on a noncombustible surface.

• Do not parallel charge batteries of varying age and charge status.

• Do not overcharge Li-ion batteries.

No; however, EHS can help. Li-ion or equipment containing Li-ion batteries are considered “dangerous goods” because they can pose significant safety risks in transportation. If you must ship Li-ion batteries or equipment containing Li-ion batteries, contact EHS for assistance. EHS has qualified staff with specialized training in shipping dangerous goods.

For your awareness: Failure to comply with regulations for shipping hazardous materials can result in significant civil penalties for the shipper of up to $100,000.00 per violation; $235,000 if the violation results in a serious injury, death or substantial damage to property.

Absolutely, proper lithium battery storage is critical for both battery performance as well as for your safety.

• Store Li-ion batteries at room temperature.
• Li-ion/LiPo batteries should never be stored fully charged. When not in use, store the Li-ion/LiPo battery pack at about 50% of the pack’s rated capacity.
• Remove the battery from a device before storing.
• Use a Li-ion/LiPo battery fireproof safety bag or other fireproof container when storing batteries.
• Cell terminals must be protected by covering them with non-conductive electrical tape.
• Have a reserved storage area for Li-ion/LiPo batteries ONLY. It must be a cool and dry place, away from heat sources and separated from any combustible materials.
• The ideal surface for storing Li-ion batteries is concrete, metal, ceramic or other non-flammable material. A rated metal flammable cabinet is also an option.
• A smoke detector should be located in the battery storage area.
• A class ABC or CO2 fire extinguisher should be readily available near the storage area.
• Do not store Li-ion batteries on loading docks, behind buildings, in basements or in stairwells.
• Do not store Li-ion or equipment containing Li-ion batteries under any stairway, indoors or out — do not leave e-bikes and other similar equipment near building stairs or doors where may prevent people from exiting higher floors if a fire occurs.
• Do not send Li-ion batteries to U of I Surplus or through Campus Mail.
• Do not store malfunctioning or bad Li-ion batteries. Contact EHS promptly for proper disposal.

With proper handling, the risks are minimal and these batteries are safe for daily use. Most incidents involving these types of batteries result from inadvertent mishandling and damage to the battery’s shell.