Are you storing lithium-ion batteries?

What are lithium-ion batteries?

We don’t think it is an exaggeration to state that Li-ion batteries have revolutionised the world since their market introduction some 30 years ago.

Thanks to their energy density and longer cycle life, Li-ion batteries are found in virtually all types of electrical and electronic devices. Smart phones, wearable medical devices, e-mobility devices, electric vehicles, material handling equipment and even grid-scale electric storage all benefit from the amazing strengths and characteristics of these batteries.

We have found that most of our customers are now storing and handling these batteries (or devices that contain them) in their normal operations.

How are they special?

There are at least 12 different Li-ion chemistry types, however for the purposes of this article we do not differentiate and refer to them all simply as Li-ion.

Beyond chemistry, Li-ion batteries are different to other types of rechargeable batteries due to having:

• Greater energy density
• Higher voltage per cell
• Longer cycle lives
• Improved retention of charge/longer shelf life

Since their introduction, the volumetric energy density of Li-ion batteries has increased threefold while their costs have dropped tenfold, leading to them becoming the leading source of energy for rechargeable devices.

What are the risks?

These batteries can present significant safety hazards if manufactured poorly, used incorrectly or not stored properly. Containing flammable electrolytes, damaged cells can lead to explosions, fires, injuries and environmental damage.

Perhaps the best example of the risks associated with these batteries (especially when stored in bulk), is the lithium battery fire which started on 29 June 2021 at a 6,500sqm storage facility in Morris, Illinois. Taking nearly two weeks to control, the incident involved some 80-90 tonnes of stored batteries.

Key consequences of the incident included destruction of the facility, a significant release of poisonous fumes, firefighters struggling to extinguish the blaze and the evacuation of some 1,000 homes and business in the area. Ultimately, it cost over AUD$5M to clean up the site.

Why do they fail?

There are several key factors which lead to the failure of Li-ion batteries:

• Overheating – potentially caused by storage in excessively hot areas
• Overcharging – usually caused by the use of non-designated chargers
• Short Circuit – potentially caused by use in the wrong equipment
• Mechanical damage – caused by impacts, drops or puncture accidents
• Manufacturing faults – potentially exacerbated by storage at charge levels over 30%

Key risk factors

Although no item or device should ever be considered 100% safe, there are a number of factors that can significantly alter the risk profile of Li-ion batteries:-

• New versus used – New batteries in their original packaging generally represent the lowest risk for storage and handling. Once they have been used it is difficult to know their condition and consequently, used batteries should be stored and handled differently.
• Manufacturing Quality – The quality of the design, materials used and manufacturing process all play a significant role in the stability and risk profile of these batteries. This factor includes consistency in the energy storage level for new batteries, which should be less than 50% of their capacity, ideally around 30%.
• Packaging – Good quality device packaging helps to ensure that the batteries are protected from the environment and accidental damage during transport, storage and handling. Ensure that the manufacturer has individually packaged the batteries and devices in such a way as to protect them from damage, short circuit or accidental activation.

How to reduce the risks

Although the consequences of failure can be significant, it is relatively straightforward to mitigate the risks associated with the bulk storage and handling of Li-ion batteries and devices powered by them. We recommend the following:

Regular Inspections

• Ensure that your storage areas, material handling equipment and tools are inspected for damage every day.

Separation

• Store batteries and setup charging stations at least 3 meters away from other combustibles.
• Consider grouping storage into smaller segments with adequate separation to enable containment in the event of an incident.

Minimal Charge

• Batteries in storage should have less than 50% charge level – ideally around 30%

Physical Protection

• Ensure items are individually packaged and protected from physical impacts and excessive vibration.
• Maintain appropriate temperatures in the storage areas and ensure batteries are protected from direct exposure to sunlight and water.
• Enforce qualified inspections of batteries and battery-powered equipment following drops or other physical damage.

Preparedness

• Consider a fire-rated, separate storage cabinet or charging station cabinet, depending on use and volume (e.g. charging versus storage only, new versus used batteries).
• Have an emergency plan that includes your response in the event of an incident with these batteries.
• Have response kits readily available – typically including fire rated blankets, gloves, containment drums and fire suppression media as relocating damaged items may not be possible once ignited.
• Consider keeping a non-combustible container filled with water 10 meters apart from your building where you can place batteries or containers that are displaying critical indications of failure or showing signs of physical damage.
• Training – Ensure staff are trained to spot hazards and know how to respond in the event of an emergency.

Wrap up

Billions of devices powered by Li-ion batteries are used safely around the world every day. Li-ion is a remarkable technology that has truly shaped the world we live in. From a consumer’s perspective, when Li-ion devices are used as designed and are monitored during charging, the risk of a serious incident occurring is greatly reduced.

The risks associated with the storage and handling of Li-ion batteries at scale does present some unique challenges. Even though new batteries stored in their original, individual packaging are generally the safest of these items, planning and preparation remain key to ensuring that your residual risk is kept as low as reasonably practical.

Ensure that you are aware of the regulatory obligations when transporting or storing Li-ion batteries (and devices where they are installed) and the potential impact that this can have on your insurance coverage.

Dangerous Goods Networks provide a comprehensive range of services designed to help our customers navigate the complex and ever-changing regulations and requirements associated with the transport, storage and handling of dangerous goods.

Our dangerous goods services include specialist consulting, training courses (including courses recognised by CASA and AMSA), software to support the efficient management of safety data sheets (SDS Connect) and specialist transport services.

Disclaimer: The content provided above is only intended to provide guidelines and does not constitute legal or expert advice. Please consult an appropriate professional for specific advice on dangerous goods for your business – info@dgnetwork.com.au.