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Emergency Response Approaches For Electric & Hybrid Vehicles in Türkiye

On the other hand, the contact of a lithium-based high voltage battery with
water (water used for fire extinguishing) can also lead to a hazard. Due to the
high reactivity of the alkali metal, water molecules (H O) are decomposed;
2
therefore, it causes the formation of hydrogen in the environment. Possible gas
explosions can also be triggered due to low electrostatic discharges caused
by hydrogen/air mixtures or sparks that may occur by electrical ignition. In
addition, another danger caused by the interaction of lithium-based batteries
with water is due to the potential voltage difference between the electrodes.
The potential difference of the voltage (DC) between the poles can similarly
lead to an explosion in the event of a short-circuit that may occur with water.
Such situations and similar ones may also pose a danger in terms of life safety
in high voltage propulsion batteries.
The last risk factor among the chemical risks is the hazards caused by
gaseous and liquid flammable and corrosive electrolyte leaks released from
battery cells. These chemicals may cause ignition in a similar way (VDA,
Accident Assistance). A possible crash may lead to deformation of the high
voltage propulsion battery system, modules or cells, leakage of chemicals
contained in them, or water/air entry into these cells. The contact with toxic,
corrosive, highly reactive chemicals that may emerge in such a situation may
cause serious injuries, even death risk (Hatai et al.,1986).

2. Possible Accident Scenarios Involving Electric & Hybrid Vehicles
The possible scenarios that emergency response teams may encounter for
accident situations involving electric & hybrid vehicles are listed below.
• The absence of a fire at the scene of the accident and no problems
observed in the propulsion battery of the electric & hybrid vehicle,
• Identifying that the propulsion battery of electric & hybrid vehicle
involving the accident is damaged or in a critical state, determining
that there is a possibility of a fire in the battery,
• Damage on the propulsion battery of electric & hybrid vehicle involving
the accident and starting of a fire,
• Combustion of the electric & hybrid vehicle involving the accident, but
high voltage propulsion battery still not being involved in this active fire,
In accidents involving electric & hybrid vehicles, the source of the fire
should be determined at first in case of a fire. In this sense, it is very important
whether the fire is caused by the battery or not. If the battery is damaged and
on fire, it may cause thermal leaks in the battery. Therefore, the entire high
voltage drive battery/ies (it might be group) must be cooled immediately to
prevent further damage.

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