The humidity sensor installed directly inside the power battery pack of new energy vehicles can provide early warnings for risks such as internal water ingress and humidity. However, the current situation is that most ordinary household electric vehicles do not have this configuration, although related technologies and products are rapidly developing.
Existing Solutions for Water Ingress Detection in Battery Packs
Currently, the detection of water ingress in battery packs is mainly done through two methods:
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Relying on high-level sealing rather than real-time monitoring This is the most mainstream solution at present. According to national standards, electric vehicle power battery packs must achieve IP67 waterproof (which means that under normal temperature and pressure, they can be submerged in 1 meter of water for half an hour without water ingress). This means that as long as the sealing is intact, the battery pack is designed to effectively prevent moisture intrusion. Therefore, many models do not have additional humidity sensors installed inside the pack.
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Active monitoring technology solutions In pursuit of safety, the industry is actively developing and applying various active monitoring technologies, which can be mainly divided into the following categories:
| Monitoring Solution | Basic Principle | Features |
|---|---|---|
| Insulation Resistance Monitoring | By detecting changes in the insulation resistance between the positive and negative terminals of the battery and the metal shell (ground), it can determine whether there is water ingress or moisture. | This is a core function of the BMS, which can indirectly detect insulation degradation caused by water ingress/moisture, but cannot sense early traces of moisture. |
| Dedicated Humidity/Water Ingress Sensors | Sensors are arranged in key positions inside the battery pack (such as the bottom, below the cooling system) to directly detect humidity or liquid. | This is a direct and active monitoring solution that can detect moisture intrusion or water ingress risks earlier, representing a trend in technological development. |
Emerging Integrated Sensor Solutions
Integrated sensor modules specifically designed for battery environment monitoring have already been developed. For example, a module developed by a certain technology company integrates water ingress, temperature, and humidity monitoring functions into a single sensor.
- Working Principle: Placing it inside the battery pack allows for real-time monitoring of environmental humidity and the presence of liquid.
- Core Value: This module can advance risk warnings, with tests indicating that it can provide a 30-minute early warning for electrolyte leakage risks, significantly reducing the accident rate.