Why do battery terminals need to be protected?
Oxidised battery terminals look untidy. But it is far more unpleasant that corrosion penetrates the contact patch between the battery terminal and the cable connected to it. As a result the effective contact area is reduced and the electrical resistance grows. This creates an increased load on the vehicle’s electrical equipment, in particular on the alternator, leads to undercharging of the battery and, at high electricity consumption, causes severe heating of the terminals. But the most important thing is that poor contact between the terminals leads to a significant drop in the starting current, and when the engine is being started the battery simply cannot deliver all the necessary power through the poor contact.
How should battery terminals be cleaned?
Some people advise using petrol or other solvents to clean battery terminals. This is not the best method, if only because petrol and most solvents are easily flammable. The oxides that form on battery terminals are quite soft, so we recommend cleaning the terminals with an ordinary wire brush or fine abrasive paper. This is the quickest and most effective method.
How can battery terminals be protected from corrosion?
There are several ways of protecting battery terminals from corrosion.
- The so-called old-fashioned method, which old drivers used long ago. You need to take two felt gaskets with holes equal to or slightly larger than the diameter of the battery terminals and soak them in machine oil. Put one gasket onto the battery terminal, then fit the cable terminal on top and place the second gasket on it. Oil-soaked felt gaskets will give reasonable protection of the terminals against excessive corrosion.
- You can also coat the terminals with any grease, for example Litol or graphite grease. The main thing is that the grease is thick enough and is not afraid of moisture. This method is quite effective, but grease collects a large amount of dirt, and so the terminals will soon look rather untidy.
- Another piece of advice that can be found on the Internet is to coat the terminals with silicone lubricant. The recommendations say that it works in roughly the same way as any grease, but does not collect as much dirt. However, it is worth bearing in mind that silicone lubricants can be quite fluid and have very high penetrating ability. They can get between the terminals and act as an insulator, considerably reducing the contact area.
- The best solution is a special varnish for protecting battery terminals. It creates a durable protective film on the surface of the terminals which does not wear off over time and reliably protects the terminals from the aggressive external environment.