Why Does My Car Battery Die When It Rains?

Does Idling a Car Charge the Battery?


Has your vehicle been caught in heavy rain or exposed to too much water? So, you may be thinking about the battery’s condition, how healthy it is, and how dangerous it is.

This article, namely “Why Does My Car Battery Die When It Rains?”, prepared in this direction, discussed whether the car battery gets wet under rainy weather conditions, what kind of situations it can cause if it gets wet, and whether it is possible to change the battery in rainy weather in cases of necessity.

Can a Car Battery Get Wet?

Your battery can get wet even if polypropylene resin, which absorbs moisture, is used as the building material of it. In this context, do not question whether the battery will get wet if it was outside in the rain, or water was spilled on it, or if water enters the interior of your car due to a minor accident at the beach; yes, it can get wet.

Why Does It Get Wet?

As said before, your car battery’s outer shell is constructed of polypropylene resin. That is to say, the lead acid and moisture are kept within your battery by its waterproof substance. Water leaking inside batteries can happen in the areas around terminals and coverings where water might be poured as well. Moreover, a car battery may often be exposed to water without harm. 

What Happens If Your Car Battery Gets Wet?

change a car battery

We can say that nothing happens. HOWEVER, although it is nothing from a little wetness, depending on the humidity rate of the water and the operation and the performance of your vehicle, that wetness leads to moisture in your vehicle’s battery and then oxidation. This, of course, doesn’t mean “nothing happens.”

Are Car Batteries Waterproof?

As just mentioned, it is the polypropylene resin lead-acid, which is the structural material of the batteries and covers the exterior of the battery. It is a waterproof material that does not allow water to enter the battery. So for this reason, and in light of the information given above, even if your battery contains water, it is not affected by water.

Of course, in line with all that has been said, we do not recommend or advocate that you submerge your battery under water or leave it completely soaked. As a result, although it is usually not a very big event, getting your battery wet is a situation that can lead to hazardous situations, but it is necessary to be careful not to cause such problems.

To put it in another way, your battery is not waterproof; it is water-resistant.

Types of Car Batteries

In this light and frame of this subject, it would be correct and appropriate to talk about two types of batteries; submerged sealed batteries and submerged vented batteries.

  • Submerged Sealed Car Batteries: As the name suggests, sealed car batteries are battery types that do not allow any liquid transfer either outside or inside. Naturally, this type of battery not only keeps the main battery dry but also prevents or at least delays water reaching it in cases where the battery is completely exposed to water.
  • Submerged Vented Car Batteries:  On the other hand, vented batteries are the type that allows the gas to be transferred out with the increase in pressure, as well as allowing water to enter the battery.

Can You Change a Car Battery in the Rain?

How to Connect a Car Battery?

Although we suggest that your vehicle’s battery should not come into contact with water or rain too much unless you have to, we would also like to shed light on whether it is possible to change the battery in rainy weather. Yes, you can change your car battery in the rain. However, although there is no problem in terms of security, it is necessary to take all kinds of security measures.

How to Prevent the Worse Scenario while Changing the Car Battery in the Rain?

  • Pay Attention to Corrosion Symptoms: It was mentioned above that your battery has sufficient water resistance, but it was also said that this resistance is at a specific limit. Namely, in case of exposure to certain humidity, your battery, which experiences oxidation, becomes useful neither to your vehicle nor to you.

For this, you should check whether your battery has signs of oxidation, regardless of before or after rain. You can diagnose it as a greenish powdery substance formed by the combination of a mix of acidic fluids, generally seen at the battery’s terminals.

  • Keep Your Battery Clean & Dry: As a second step, keep your battery clean and dry whenever possible. Although it is resistant to water thanks to its outer substance, you will both ensure its cleanliness and meet the need for dryness with the help of a brush with thin bristles, like a toothbrush, to stay away from liquids and not absorb moisture.

Are Wet Batteries Dangerous?

How Long Does It Take to Charge a Car Battery?

If you are asking this question in the context of electric shock, no wet batteries are not dangerous and will not electrocute you. However, when we focus on the general and big picture, we would like to state that we do not recommend it because it has dangerous aspects.

Namely, polypropylene resin, which we have repeatedly emphasized and used as the outer material of the batteries, prevents the transmission of liquid into the battery and ensures that the battery is resistant to water, so when it gets wet, the batteries do not directly damage them.

However, your battery, which starts to oxidize over time, can cause severe accidents by damaging your vehicle, and oxidation with skin contact can also cause damage to your skin. So, in short, we can say that, not directly but obliquely, they get dangerous and harmful for you and your vehicle.


Although car batteries, resistant to water due to their structural material, can get wet, they do not cause direct electric shocks or any danger; they can damage the battery over time and cause accidents. As a result, you can replace your battery as it will not be adversely affected under wet weather conditions such as rain; a small suggestion is to keep your battery clean and dry.

Leave a Comment

Your email address will not be published. Required fields are marked *