Just wondering. Last time in 2011 the was a surfeit of electric cars.

EV battery packs and drive units are heavily sealed.

^ with accent on the heavily? 555

Floods and cars, particularly including EV's are a bad combinaton. EV bateries are not sealed, they have venting systems. Gemini says: an EV battery vent can allow water damage if the vehicle is submerged too deeply or for too long. [1, 2]

While the vent's breathable ePTFE membrane is engineered to naturally repel liquid water while allowing air to pass through, it has a physical limit. If the water pressure exceeds the membrane’s physical threshold, the barrier will breach, and water will flood the battery pack. [1, 2, 3, 4]

The Submersion Threshold: How Deep is Too Deep?

Most EV battery packs are built to meet the IP67 ingress protection standard. [1, 2, 3]

• The 1-Meter Limit: Under static (still) water conditions, an EV battery pack is rated to survive submerged in up to 1 meter of water for 30 minutes without leaking. [1, 2]

• Beyond 1 Meter: If the battery is submerged deeper than 1 meter, the hydrostatic pressure becomes greater than the vent membrane and seals are designed to withstand. The membrane will fail, letting water inside. [1, 2]

Factors That Cause Early Failure

Even in less than 1 meter of water, the vent or battery pack can leak due to two major automotive variables:

1. Dynamic Pressure (Moving through water): The 1-meter rule assumes the car is sitting perfectly still. If you drive an EV through floodwaters, the forward momentum creates a "bow wave." This dynamic movement generates significantly higher water pressure against the vents and seals than standing water does, causing them to fail at much shallower depths. [1]

2. Thermal Shock (The Vacuum Effect): When a vehicle is running, the battery pack gets warm. If the car is suddenly plunged into cool floodwater, the rapid drop in temperature causes the air inside the battery pack to contract sharply. This creates an internal vacuum that actively sucks water through the vent membrane and into the enclosure. [1, 2]

The Result of Water Ingress

If water breaches the vent, it creates short circuits across the high-voltage cells. While the car's automated safety systems will immediately isolate the high-voltage system to protect passengers from electrocution, the trapped water (especially salt water or dirty floodwater) will cause corrosion. This frequently leads to internal short circuits and delayed thermal runaway (battery fires) hours or even days after the submersion occurred. [1, 2, 3, 4, 5, 6, 7]

8 minutes ago, Jitar said:

Floods and cars, particularly including EV's are a bad combinaton. EV bateries are not sealed, they have venting systems. Gemini says: an EV battery vent can allow water damage if the vehicle is submerged too deeply or for too long. [

, 2]

While the vent's breathable ePTFE membrane is engineered to naturally repel liquid water while allowing air to pass through, it has a physical limit. If the water pressure exceeds the membrane’s physical threshold, the barrier will breach, and water will flood the battery pack. [1, 2, 3, 4]

The Submersion Threshold: How Deep is Too Deep?

Most EV battery packs are built to meet the IP67 ingress protection standard. [1,

, 3]

• The 1-Meter Limit: Under static (still) water conditions, an EV battery pack is rated to survive submerged in up to 1 meter of water for 30 minutes without leaking. [

  , 2]

• Beyond 1 Meter: If the battery is submerged deeper than 1 meter, the hydrostatic pressure becomes greater than the vent membrane and seals are designed to withstand. The membrane will fail, letting water inside. [1, 2]

Factors That Cause Early Failure

Even in less than 1 meter of water, the vent or battery pack can leak due to two major automotive variables:

1. Dynamic Pressure (Moving through water): The 1-meter rule assumes the car is sitting perfectly still. If you drive an EV through floodwaters, the forward momentum creates a "bow wave." This dynamic movement generates significantly higher water pressure against the vents and seals than standing water does, causing them to fail at much shallower depths. [1]

2. Thermal Shock (The Vacuum Effect): When a vehicle is running, the battery pack gets warm. If the car is suddenly plunged into cool floodwater, the rapid drop in temperature causes the air inside the battery pack to contract sharply. This creates an internal vacuum that actively sucks water through the vent membrane and into the enclosure. [1, 2]

The Result of Water Ingress

If water breaches the vent, it creates short circuits across the high-voltage cells. While the car's automated safety systems will immediately isolate the high-voltage system to protect passengers from electrocution, the trapped water (especially salt water or dirty floodwater) will cause corrosion. This frequently leads to internal short circuits and delayed thermal runaway (battery fires) hours or even days after the submersion occurred. [1, 2, 3,

, 5, 6, 7]

Key points ... ' too deeply & too long ', as with any car. Difference being, not too deep, or too long, and almost no effect on EV parts.

Little deeper, and EV would actually make it through, still running ... but ...

My POS ICEV, Vios and or Mazda2, had to replace wheel bearings as not sealed. So ICEV or EV, I'd be avoiding water above the lower part of rubber on tires, so yea, 10cm maybe.

You really got to be an idiot to drive through deep water, anything close to the floor. Especially ICEV unless fitted with a snorkel.

Edited yesterday at 11:14 AM1 day by KhunLA