What mixture do lead-acid batteries use?

Lead-acid batteries utilize a mixture that consists of sulfuric acid and water to create an electrolyte solution. The typical concentration of sulfuric acid in a fully charged lead-acid battery is around 30%. This means that 30% of the solution is sulfuric acid, while the remaining 70% is distilled water. This specific ratio is essential for the battery’s chemical reactions during charging and discharging, as it ensures optimal performance and longevity of the battery.

In a lead-acid battery, the sulfuric acid interacts with the lead plates, allowing for the storage and release of electrical energy. A higher concentration of sulfuric acid could lead to excessive corrosion and damage to the internal components of the battery, while too little could result in insufficient electron transfer and decreased capacity. Therefore, the mixture's balance is crucial for effective battery operation.

The other options suggest concentrations that are either too high or too low for the optimal functioning of lead-acid batteries.