Can boiled water be used as a substitute for battery fluid?

[DeTheo]

Battery fluid cannot be replaced with boiled water. The following explains the reasons why it cannot be substituted and the preparation ratio of battery fluid: Reasons why it cannot be substituted: Because boiled water contains ions, which will increase the self-discharge of the battery. You can add battery fluid or distilled water. Battery fluid can be replaced with purified water. Preparation ratio of battery fluid: Battery fluid is prepared by mixing special sulfuric acid and distilled water in a certain ratio, with a density generally ranging from 1.24 to 1.30 grams per cubic centimeter. The specific gravity is 12.75-12.85 g/cm³ of sulfuric acid mixed with pure water. If the water in the battery is exhausted during use, simply add pure water and charge it.

[BentleyRose]

I've been in car maintenance for many years, and you can't just mess around with batteries. The battery fluid is a mixture of dilute sulfuric acid and distilled water, which provides the electrolyte for charging and discharging the battery. Boiled water is just regular water that's been heated, lacking the essential sulfuric acid component. Adding it will dilute the electrolyte concentration, disrupting the internal chemical reactions of the battery. At best, the battery might lose charge and fail to start; at worst, the electrode plates could corrode, the battery might swell or even explode and leak acid, damaging the car's electrical system or causing harm to people. The correct approach is to use distilled water from the supermarket to top it up if the fluid level is low—don't cut corners and end up with bigger problems. Regularly check the battery's condition to avoid low fluid levels during the high temperatures of summer.

[LeBrady]

As a young car enthusiast who loves tinkering with vehicles, I once got curious and tried something that almost ended badly. The battery fluid is essentially diluted sulfuric acid water, responsible for conducting electricity and storing energy on the lead plates. Boiled water has high temperature and impurities, and even after cooling, adding it can disrupt the acid balance, drastically reducing the battery's charging and discharging efficiency. Unstable voltage might cause the car to stall on the road. The result could be a completely dead battery, wasting hundreds of dollars on a replacement. It's better to stick with dedicated battery replenishment fluid or distilled water—simple, safe, and cheap. Maintaining a battery isn't hard; just keep an eye on the electrolyte level.

[MaxLynn]

The key to battery fluid lies in the electrolyte concentration balance. Boiled water lacks sulfuric acid components, disrupting the chemical balance and accelerating plate sulfation, leading to a sharp drop in battery capacity. This can cause issues such as slow charging and high discharge resistance, affecting vehicle startup. When topping up, use distilled water only and avoid adding impurities.