The first use of a lithium-ion battery in an electronic device dates back to the early 1990s. 30 years later, this technology has evolved and is now part of our everyday lives. In particular, it is present in electric vehicles (from cars to scooters and bicycles, not to mention motorcycles and forklifts), which are becoming more and more common on our roads, as well as in enterprises.
However, as with any technology, its use is not without risk. Users must be aware of these risks and take preventive measures to manage them. The ultimate goal is to prevent them from occurring in the first place.
What do you need to know about lithium batteries?
Before discussing the risks associated with this type of battery, it’s important to remember that it consists of cells containing electrodes (an anode and a cathode), a separator, and electrolyte.
When connected to a vehicle, electrons flow from one electrode to the other through an external circuit. During charge cycles, they flow from the cathode (positive electrode) to the anode (negative electrode). Conversely, during discharge cycles, electrons flow from the anode to the cathode.
In addition to lithium, most batteries contain a number of other components, including nickel, manganese, and graphite.
What are the dangers of this type of battery?
The lithium-ion battery stores, accumulates, and releases energy. Therefore, it can be dangerous to use it in certain situations, which can damage it and cause thermal runaway. This can happen in the case of
- Mechanical shock ;
- Exposure to very low or very high temperatures ;
- Overload or excessive discharge ;
- Short circuit ;
- Manufacturing defect.
Likewise, it should be noted that thermal runaway can occur up to 48 hours after damage to the battery of an electric vehicle (such as a shock in an accident).
What are the risks associated with its use?
There are several risks associated with lithium-ion batteries, especially with their high energy density:
- Leak of the electrolyte, which is flammable, after an impact;
- Explosion due to high temperature, e.g. as a result of overcharging or external short circuit, leading to thermal runaway;
- Emission of gases, vapors, sparks and flames, e.g. after overcharging, deep discharge or exposure to high ambient temperatures.
However, the greatest risk – and the most widely publicized – is explosion due to thermal runaway of the battery, resulting in fire.
How can the risks associated with lithium batteries in electric vehicles be prevented?
To reduce the risks associated with the use of a lithium battery, preventive measures must be taken. For example:
- Do not expose to very low or high temperatures;
- Do not store or use damaged batteries;
- Always use the correct charger when recharging an electric vehicle.
There are also various regulations in France and Europe that manufacturers must comply with, some of which are specific to electric vehicles.
As for companies using lithium-ion batteries, they must inform their employees of the risks and take the necessary preventive measures (posting, monitoring, risk analysis, provision of fire-fighting equipment such as the Flamastop fire blanket, etc.).