Lithium batteries are ubiquitous in modern life, from smartphones to electric cars, they power our devices. However, many people know little about the water resistance of lithium batteries and even have misconceptions about them. In this article, we look at the potential risks of lithium batteries coming into contact with water, recommendations for preventing water ingress, and steps to take after accidental water exposure.
The basic structure and working principle of lithium battery
Lithium batteries, especially lithium-ion batteries, store and release energy through the movement of lithium ions between the positive and negative electrodes. The positive electrode is usually made of materials such as lithium-cobalt oxide and lithium-nickel-manganese-cobalt oxide, while the negative electrode is graphite or other carbon materials. The electrolyte is then responsible for transporting the lithium ions between the two electrodes. This process requires that the inside of the battery be kept dry, as moisture can react with the chemicals in the electrolyte, leading to degradation of the battery's performance or even short-circuiting.
Potential Risks of Lithium Batteries in Contact with Water
Although lithium batteries are relatively sealed by design, contact with water can still pose a number of risks. Firstly, water is a good conductor of electricity, and contact with the battery may result in a short circuit. A short circuit will not only cause the battery to lose function, but may also cause a fire or explosion.
Secondly, water molecules may trigger electrolyte leakage if they penetrate into the interior of the battery. The resulting chemical reaction may affect the internal stability of the battery, leading to accelerated ageing or reduced performance.
In addition, the presence of water will also greatly increase the probability of damage to the various components of the battery, especially when used in a long-term humid environment, the risk of corrosion of circuits and components will increase, which in turn affects the service life and safety of the battery.
Waterproof performance of different types of lithium batteries
There are differences in the waterproof performance of lithium batteries in different usage scenarios. Li-ion batteries in some consumer electronics, such as smartphones and smartwatches, are usually designed with a certain waterproof rating, such as IP67 or IP68, which means they can be immersed in a certain depth of water for a short period of time.
And Li-ion batteries in electric vehicles, such as electric cars, are usually designed with more stringent waterproofing measures to ensure their safety in various climatic conditions. And in industrial equipment and special-purpose lithium batteries, although they are sometimes designed to be waterproof, they still need to pay special attention to the usage environment and avoid contact with liquids.
How to deal with lithium battery contact with water
Once the lithium battery is found in contact with water, the following measures should be taken immediately:
- Disconnect the power: If the device is still running, switch off the power immediately.
- Remove the battery: Remove the battery from the device as quickly as possible.
- Drying treatment: Use a dry, non-static cloth to gently wipe the surface of the battery, then place it in a well-ventilated area at a suitable temperature to dry naturally, avoiding the use of hot air to prevent internal short circuits.
- Professional Inspection: Even if the battery appears to be dry, it should be sent to a professional repair centre for inspection to ensure that there is no internal damage.
Suggestions for preventing water ingress into lithium batteries
To minimise the risk of water ingress into the lithium battery, users can take the following precautions:
- Use a waterproof case: Ensure that the device has a good seal when used in a humid environment.
- Avoid high humidity: Try to avoid direct exposure of electronic devices in rainy or humid places.
- Regularly check the device: Check the battery status regularly to ensure there is no external damage.
Can I charge a wet lithium battery?
Charging a wet lithium battery is not recommended. Moisture may cause a short circuit, which could result in a fire or damage to the charging device. It is important to avoid charging behaviour until you are sure the battery is completely dry.
How to charge lithium batteries
Can lithium batteries be left outside?
Lithium batteries are able to be used outdoors, but it should be noted that continuous exposure to direct sunlight, high temperatures, or moisture will affect the performance and life of the battery. It is best to store lithium batteries in a dry, cool place and protect them with a case that has good sealing properties.
What is the IP65 rating?
IP65 is a dust and waterproof rating standard that means the device is completely dustproof and can withstand low-pressure water jets from any direction. When choosing an electronic device, knowing its IP rating can help users make a choice and ensure that the product they buy is adequately protected for the environment in which it will be used.
Are lithium marine batteries safe enough?
Marine lithium batteries are specifically designed to cope with special environments such as moisture and vibration. Many marine lithium batteries are waterproof and have been rigorously tested to ensure safety for use at sea. However, for specific products, users still need to verify their performance specifications and compliance to ensure safe use.
Can lithium batteries continue to be used after water ingress?
If a lithium battery has been exposed to water, it should not continue to be used unless it has been professionally inspected and confirmed to be undamaged. Continued use of a damp battery may result in greater safety hazards, including short circuits, fires, and other dangerous situations. Always follow safe operating procedures and seek professional advice promptly.
Summary
Lithium batteries may cause safety hazards when exposed to water during use, so it is important to understand how they work and the relevant protective knowledge. Proper precautions and timely handling can help users minimise risks and ensure that lithium batteries safely and reliably power our equipment. When using lithium batteries, everyone should remain vigilant and follow the safety guidelines to protect their equipment and life and property.
