Electric Vehicles and Water: Driving Safety in Heavy Rain and Floods

Sudden and heavy rains that we encounter in Turkey, especially during the spring and winter months, can lead to puddles on the roads and sometimes floods. The risk of internal combustion engine vehicles drawing water into their engines while driving through water is known by everyone. But are electric vehicles (EVs), which do not have an air intake system or exhaust, safer for driving through deep water? In this article, we examine the interaction of electric vehicles with water and the vital details that need attention in rainy weather.

1. Interaction of Electric Vehicles with Water

Electric vehicles operate with high voltage (generally between 400V and 800V) electrical systems. The combination of water and electricity is always a valid source of concern. However, modern electric vehicles are designed to remain unaffected by daily rain, snow, or puddles.

The battery packs and electric motors in vehicles produced by Tesla, Togg, Audi, and many other brands have high sealing standards such as IP67 or IP68 (Ingress Protection). These standards indicate that the system is fully protected against dust and is insulated against short term immersions in water of a certain depth (for example, up to 1 meter). Therefore, while your vehicle is parked in the rain or driving through a standard puddle, the system will not short circuit or create a risk of electric shock.

2. Battery Location and Contact with Water

In order to lower the center of gravity and improve handling in electric vehicles, battery packs are placed on the floor of the vehicle, specifically in the section called the "skateboard chassis". Although this provides a great advantage in terms of driving dynamics, it makes the battery the closest and most vulnerable component to water during floods.

Even though the system is perfectly insulated from the factory, water may leak into the battery due to reasons such as:

• Physical impacts previously received by the vehicle floor

• Wear of the insulation seals over time or due to temperature changes

• Pressurized water (the wave effect created during fast crossings) forcing the insulation points

Water reaching the battery cells causes irreversible damage and may require a complete battery replacement.

3. Driving Through Floods and Associated Dangers

The biggest misconception many users fall into is thinking that electric vehicles can be used like submarines because they do not need an air intake. Manufacturers' user manuals are very clear on this matter:

• "Driving through water covered roads can cause serious damage to the propulsion system, driving system and electrical system of the vehicle." Water leaking into high voltage electronic components and the conductive materials it contains cause permanent short circuits even if they dry out, seriously impairing the safety systems of the vehicle. The manufacturer mandates contacting an authorized service without delay in case of such water contact which carries major safety risks.
• "Do not drive your vehicle on a flooded road where the depth exceeds the lower edge of the rims."
• The user manual states that water exceeding the bottom of the vehicle (battery level) must never be entered. It is clearly emphasized that if deep water puddles are crossed, the vehicle may be damaged and water related damages will remain outside the warranty coverage.
• The maximum wading height in the manuals is generally limited to the level of the lower rocker panel or wheel hub of the vehicle (approximately 300 mm). If driving through water is to be done, it is stated that the water must be still and the vehicle must never exceed walking speed (approximately 5 km/h). Fast crossings create a "wave" that causes water to accumulate in front of the vehicle and rise up to the hood level.
• Even though its battery has high IP standards, entering deep and flowing waters endangers driving safety for Togg, just as it does for all modern vehicles.

The basic rule is this: Do not enter any puddle where you cannot clearly see the depth or the ground underneath, regardless of the vehicle type.

In summary; your electric vehicle is extremely safe in daily rain, but it is not a submarine. On days with heavy rain and flood warnings, choosing your route from main arteries with a low risk of water accumulation and looking for an alternative route when you encounter deep waters is the safest approach.