Fillers for the Transportation of Damaged Lithium-Ion Batteries at a Glance
The transport of damaged lithium-ion batteries poses a significant challenge. Lithium-ion batteries are widespread in many electronic devices and offer high energy density with relatively low weight. However, defective batteries carry a high risk of overheating, short circuits, or even fires. These hazards are amplified by mechanical damage, faulty electronics, or improper storage.
In addition, strict regulations apply to the transport of these batteries, particularly with regard to international dangerous goods transport. To minimize risk, it is necessary to take special precautions that go beyond simple packaging solutions.
Why are special fillers for transport necessary?
Lithium-ion batteries can enter a thermal runaway when defective or mechanically damaged, leading to intense heat generation and potentially triggering fires. Simple packaging materials such as cardboard or plastic do not provide sufficient protection in such cases. This is where special fillers come into play, designed to ensure safety during transport.
The task of these fillers is to insulate the batteries, absorb potential heat development, and prevent the outbreak of flames. Without these special fillers, the transport of defective lithium-ion batteries would be practically unfeasible.
What fillers are there?
There are various fillers developed specifically for the transport of lithium-ion batteries. They can be broadly divided into two categories: inert fillers and actively cooling fillers.
Inert fillers
Inert fillers primarily serve physical insulation and protect the surroundings from potential hazards. They do not conduct heat and help cushion mechanical shocks.
Vermiculite
Vermiculite is a mineral that expands when heated and is therefore especially suitable for insulation. It is commonly used as loose filler material and provides very good heat and impact dampening.
Advantages of vermiculite:
- Very heat resistant
- Good shock absorption
- Cost-effective
Disadvantages of vermiculite:
- Relatively heavy
- No active cooling
Perlite
Similar to vermiculite, perlite is a porous mineral material that also provides good insulation. It is often used for the transport of dangerous goods because it is flammable and can withstand high temperatures.
Advantages of perlite
- Low weight
- High temperature resistance
Disadvantages of perlite
- Lower mechanical damping compared to other fillers
Active cooling fillers
Active cooling fillers go a step further by not only insulating but also actively absorbing the heat that can develop in a defective battery. They can lower the temperature of the battery and thus reduce the risk of thermal runaway.
Pyrobubbles
Pyrobubbles are small, hollow glass bubbles that exhibit high temperature resistance and can effectively absorb thermal energy. They have excellent insulating capabilities and are non-flammable, making them an ideal filler for the transport of defective batteries.
Advantages of Pyrobubbles
- Extremely heat resistant
- Lightweight
- Environmentally friendly
Disadvantages of Pyrobubble
- Higher cost than inert fillers
Special gels and mats
In some cases, special gels or mats are also used, which have the ability to absorb the heat generated and actively cool the battery. However, these materials are often more expensive and more complex to handle.
Advantages of gels and mats
- Active cooling
- High protection under extreme conditions
Disadvantages of gels and mats
- High cost
- Complex application
Pros and cons of fillers
While inert fillers such as vermiculite and perlite are characterized primarily by their cost efficiency and easy handling, they do not provide active protection against thermal hazards. They only insulate and reduce the effects of mechanical shocks. Actively cooling fillers such as Pyrobubbles or special gels are more expensive, but offer substantially higher protection by the ability to actively absorb heat and thus significantly reduce the risk of fire.
