Moisture
In a hot and dry climate, metal is much less prone to rusting than in a humid or wet climate. Rust is the byproduct of a process called "corrosion." Metal corrodes when it goes through a chemical reaction involving the oxygen in water. If the metal is kept dry at all times, it is much less likely to start rusting than if it is constantly being exposed to rain or to high humidity that condenses on the metal.
Temperature
Heat also plays a part in how fast metal rusts. Generally speaking, higher temperatures are associated with higher rates of corrosion. Therefore, the temperature caused by the weather may affect how fast metal rusts. You can generally expect less rust in the winter and more in the summer; however, this can change based on other factors. For instance, a lower temperature but increased humidity could still lead to increased rust.
Winter Weather
Winter weather affects the rate of metal rusting from a cause beyond the temperature and moisture factors. When a region receives a great deal of snow or ice on the roads, the result is that the local department of roads or highways will put salt or other de-icing substances down on the roads. Salt and other substances put down to deal with icy roads greatly increase the rate at which rust forms on buildings, vehicles and other structures.
Acid Rain
Although all rain will speed up the rate of corrosion, acid rain will accelerate it much more. Acid rain can be caused by pollution and unregulated industry, and natural occurrences such as volcanic eruptions also contribute to the problem. Any metal on buildings, cars or on a property will rust faster if exposed to prolonged bouts of acid rain. The speed at which acid rain accelerates rust depends partly on how low the pH of the water has dropped compared to a normal level of 5.6.
Using some of the resources here on the site we find this post about What Causes Battery Terminal Corrosion
User @Paulster2 Says:
Corrosion on the terminals is due to hydrogen gas being released from the acid in the battery. It mixes with other things in the atmosphere under the hood and produces the corrosion you see on the terminals. Generally, if the corrosion is occurring on the negative terminal, your system is probably undercharging. If on the positive side, it is probably overcharging. Most often it will be seen on the negative side because the battery is usually in an undercharged situation.
Greenish/Bluish
The picture above is of the positive terminal. The Greenish-Bluish "fuzz" is likely Copper Sulfate that’s been exposed to a bit of moisture. This is formed when the copper in the terminal-clamp reacts with the lead in the battery terminal, helped along by the transmission of electrical current and sulfuric acid from inside the battery, and maybe seeping out a bit from various seams. This known as a Galvanic Corrosion (Bimetal Corrosion)
The chemical reaction looks like this:
Cu (s) + 2 H2SO4 (ℓ) → CuSO4 (aq) + 2 H2O (ℓ) + SO2 (g)
This copper sulfate does not conduct electricity very well, which is why battery performance will degrade (and, with that, you’ll get other electrical issues), and why it’s a good idea to clean this stuff off the terminals and groounds. Baking soda and water are good for removing the corrosion, because the baking soda will neutralize the acidic copper sulfate.
White Powdery Corrosion
White Powdery Corrosion on/around the negative terminal is the result of a process called sulfation, and it’s usually caused by a lead-acid battery not being charged enough.
Some common causes:
Batteries sit too long between charges. As little as 24 hours in hot weather and several days in cooler weather.
Battery is stored without some type of energy input.
Undercharging of a battery to only 90% of capacity will allow sulfation of the battery using the 10% of battery chemistry not reactivated by not completing the charging cycle.
Low electrolyte level - battery plates exposed to air will immediately sulfate.
Incorrect charging levels and settings. Rolls recommends a 3-phase charge cycle (Bulk, Absorption & Float) and a charge rate equal to 10% of the C20 (20 hr AH rating) of the battery bank. See State of Charge & charging information.
A battery sitting for extended periods in a partial or discharged state is more likely to retain a build up of sulfation, which hardens and is more difficult to remove through equalizations.
According to Battery University this is what sulfation is:
During use, small sulfate crystals form, but these are normal and are not harmful. During prolonged charge deprivation, however, the amorphous lead sulfate converts to a stable crystalline and deposits on the negative plates. This leads to the development of large crystals that reduce the battery’s active material, which is responsible for the performance.
This appears to be the chemical reaction between lead and sulfuric acid that causes lead sulfate:
Pb (s) + H2SO4 (aq) → PbSO4 (aq) + H2 (g)
The sulfation primarily happens on the battery’s internal plates, but leaks of sulfuric acid where the terminal (usually made of zinc and lead) exits the plastic battery housing can cause the sulfation to occur outside the battery.
It can be concluded that warm and humid weather, such as most spring days, can indeed accelerate corrosion. This does align with the possibility that a snap-change in weather might bring about an electrical conductivity issue which may not have been present during previous stable cooler and/or dryer conditions.
