Power battery waterproof performance directly affects the use of new energy electric vehicles safety, major battery companies and vehicle manufacturers will carry out rigorous waterproof testing of batteries
Interpreted in accordance with the 2015 version of the national standard GB/T 31485-2015.The method of making airtight is seawater immersion.The
Battery fully charged, immersed in 3.5% NaCl solution for 2h, the whole solution is submerged in the battery, observe for 1h to see whether there is any fire, explosion phenomenon.
Application Scenario: Vehicle is parked in heavy rain, falls into water, and the area around the battery pack is soaked with water.
However, after the 2020 national standard, the mandatory requirement for seawater immersion test for batteries has been canceled, but as far as I know, battery companies / car companies basically still do similar watertightness test.After all, when something goes wrong, the brand is still directly affected. The public airtightness test that we sometimes see from manufacturers is that manufacturersThe entire battery pack was completely immersed in salt water, and after soaking for a while, the entire pack worked as usualThe
There are also manufacturers to do public experiments battery packs energized, immersed in a meter deep fish tank, more than 40 minutes after picking up, re-tested without anomalies, the power battery can be used normally.
In addition to the soak test, some battery companies also do the IPX9 test with high temperature and high pressure water spray.(Water temperature 85 degrees Celsius, water pressure test equivalent to 100 atmospheres.)
Therefore, as long as the power battery quality control management of the pure electric car, in the water occasionally submerged, as long as the chassis does not soak in the water for a long time without moving the car, basically there will be no problem. Even if there is a leakage, the BMS will detect it at the first time and carry out instantaneous disconnection.
In reality, as long as the quality of the pure electric car is good, because there is no intake/exhaust pipe, its wading ability is much better than that of the fuel car, ordinary passenger cars, if not specially designed, the wading depth limit is only 15-20cm, while the wading depth of the pure electric car can generally reach 50cm upwards, and can even reach 70cm.
But that doesn't mean you can drive a pure electric car like a boat ......
Because the power battery pack passes multiple waterproof tests before leaving the factory, it is not necessarily resistant to nature's harsh weather and poor road conditions.
Under normal circumstances, your power battery pack is able to resist a meter of water depth for two to three hours with no problem, but if there are usually cuts and scrapes, sharp stones damage the battery pack's shell and cracks appear. Or the rubber parts of the chassis sealing have been in too hot and too cold environment for a long time, and have aged and dried out in advance, all of which may allow water / water vapor to enter the periphery of the battery pack.
In addition, oil, acid and corrosive substances on the road for a long time adhere to the chassis on top of the battery housing, especially some battery pack housing is too low to the ground and poorly protected. This may cause the sealing of the battery pack to deteriorate after a long period of driving, and eventually lead to water / water vapor entering the battery case under the pressure of external water pressure when wading.
So you can't expect a car company's power cell protection 100% to be effective, and a demonstration new car (as advertised) will be fine for extended periods of time under water (more than 30 minutes), or parked for an hour or two where the water can submerge the chassis. But that doesn't mean that all production models are still up to that level after a few years of driving. High-frequency vibration, high humidity, high heat, low temperatures, external corrosion, trauma, or design flaws in some brands can make inadvertent wading lead to water in the battery pack.
For example, there was a news story that a Tesla owner found that the battery pack had gotten into the water, and as a result, Tesla wouldn't pay for it, saying that the owner had waded into the water more than 200mm deep, which caused the battery pack to get into the water.
So even if you drive an electric car, if it's not specifically designed to come over to safeguard off-road wading depths, you should still be careful. Although it won't stall in the water, the manufacturer won't pay for damage to the battery pack caused by wading deeper.
Article from Knowledge: Will.liu, has been authorized by the author of the permission to reprint
