Lithium battery safety – Guidelines to follow


Lithium-ion batteries are the industry standard for all rechargeable devices today. They have higher energy densities than legacy batteries (up to 100 times higher) and have an operating voltage (V), ranging from 3.6–4.2V.

Due to the high energy densities coupled with the flammable organic electrolyte, Lithium-ion batteries have higher chances for fire hazards and accidents, causing new challenges for use, storage, and handling.

Physical damage, elevated temperature exposure, and electrical abuse such as short circuits and overcharging can cause a thermal runaway or rapid self-heating from an exothermic chemical reaction, resulting in a thermal runaway of adjacent cells.

Manufacturers’ defects such as imperfections and/or contaminants in the manufacturing process can also lead to thermal runaway. This reaction vaporizes the organic electrolyte and pressurizes the cell casing. Failure of the case results in the release of flammable and toxic gases. The severity of a runaway battery reaction is determined by the amount of pressure inside the cell, leading to a battery incident.

This post will list the best practices and guidelines for maintenance, charging, storage, handling, disposal, and recycling of Lithium-Ion batteries.


Rechargeable Lithium-Ion batteries have a finite lifespan of two to three years or 300 to 500 charge cycles, whichever comes first. They lose the ability to hold a charge over time. A charge cycle is a period of use in which the battery is fully charged, fully discharged, and then fully recharged.

Batteries should not be left unused for long periods, whether in the product or storage. Lithium-ion batteries continue to slowly discharge (self-discharge) when not in use or storage. Check the battery’s charge status after six months of inactivity and charge or dispose of it as needed. Keep an eye on batteries nearing the end of their expected life. If the battery run time falls below 80% of the original run time or the battery charge time increases significantly, consider replacing the battery.


Follow the manufacturer’s charging instructions at all times. Use chargers or charging methods designed to safely charge cells or battery packs within the specified parameters. If batteries emit an unusual odor, develop heat, change shape/geometry, or behave abnormally during operation or charging, disconnect them immediately. Remove the batteries and properly dispose of them. After charging is complete, remove the cells and pack from the chargers as soon as possible.

Batteries should be charged and stored in a fire-resistant container. Parallel charging batteries of varying ages and charge states are not recommended because chargers cannot monitor the current of individual cells, and initial voltage balancing can result in excessive amperage, battery damage, and heat generation. Before parallel charging, check the voltage; all batteries should be within 0.5 volts of each other. Overcharging (greater than 4.2V for most batteries) or discharging (below 3V) batteries are not recommended. A primary (disposable lithium or alkaline) battery should never be charged. The charger should not be used as a storage device.


Always store one-time use batteries separately from rechargeable batteries. Before long-term storage, charge/discharge the battery to approximately 50% of capacity. Store batteries in metal storage cabinets away from combustible materials at temperatures between 5 °C and 20 °C (41 °F and 68 °F). Remove batteries from the devices for long-term storage. Avoid bulk storage of batteries in non-laboratory areas such as offices.


To avoid damaging the battery casing or connections, handle batteries and/or battery-powered devices with care. Batteries should not contact conductive materials, water, seawater, strong oxidizers, or strong acids. Batteries should not be stored in direct sunlight, on hot surfaces, or in hot environments. Before using a battery, inspect it for signs of damage. Allow a battery to cool before charging, or use one still warm from charging. Keep the battery out of the reach of children. A battery should not be exposed to temperatures above 60 °C (140 °F). Excessive shock or vibration should be avoided when using the battery.

Do not touch any fluids that are leaking from a battery pack. Dispose of a leaking battery pack, and do not rub your eyes if you come into contact with the fluid. Wahs your eyes thoroughly with water, lifting upper and lower lids until no fluid remains, and seek medical attention. While transporting a Lithium-Ion battery, check all applicable local, national, and international regulations. Transporting end-of-life, damaged, or recalled batteries may be restricted or prohibited in some circumstances.

Disposal and recycling

Disposal and recycling regulations for lithium-ion batteries differ by country and region. Before disposing of any battery, check and follow all applicable regulations. Many countries make it illegal to dispose of electronic waste in regular trash cans. A battery should never be thrown away in a fire or water. A battery should not be disassembled, crushed, or punctured. Damaged or puffy batteries should never be used and should be disposed of as soon as possible.