With winter approaching many motorists find their vehicles have starting issues, often these are due to battery problems. Every vehicle requires at least one battery, these are a consumable item and will deteriorate over time due to wear and tear.
Each time a battery is cycled, i.e. discharged and charged, a small amount of the active material within the battery plates is permanently lost. Over time, this ageing deterioration will eventually result in the failure of the battery.
In cold weather, the chemical reaction between the plates and the electrolyte is slowed – at 0 degrees Celsius, a fully charged battery can lose up to 30% of its starting/cranking performance. If the battery is older, this loss may take the battery below the level of cranking performance needed to start the engine.
During the winter, the cranking requirements are increased due to the engine oil being more viscous or thicker and also the engine components have a higher resistance to rotation. All these factors can have an effect on your vehicle’s battery.
When a battery is discharged, a process called Sulphation takes place. When a battery is recharged, the Sulphation reverts back into sulphuric acid. If a battery is left to go flat for some time, the Sulphation slowly over time changes its form, to the point that it cannot revert back into sulphuric acid when charged. This is called Plate Sulphation and normally occurs in vehicles that are not used regularly or are under charged due to drive belts being slack or the alternator being faulty.
Internally, a battery has a solution which is evenly mixed; this is made up of acid and deionised water. If a battery has a stronger concentration of acid at the bottom of it, the battery will show a higher voltage and will not be able to supply enough current to start the vehicle. This is known as acid stratification and can be caused by short distance driving and using other electrical components at the same time like the radio or the lights. Another reason why batteries fail in winter.
Many car batteries failed during lockdown as people were not using their vehicles as often. If you find that you are not using your vehicle for a week or so the best advice would be to start it every few days and run it for a while, remembering to turn off all the other electrical components that could drain the battery (note: it is an offence to leave a car running unattended). If you are in any doubt pop in to your local garage, most will perform a battery test for free.
For a free battery health check, free battery fitting or free recycling of your old battery, get in touch with the experienced mechanics at Sunrise Service & MOT Centre in Blandford on 01258 459 798