Simplistically, battery charging works by applying a higher voltage across the terminals of the battery. The higher the voltage compared to the battery voltage the higher the charge rate. Alternators will charger batteries to around 80% capacity, as this is all that is needed to start the engine. To make most effective use of your battery, they need to be charged using a multi-stage charger. A 3 stage charging process is Boost, Absorbtion and Float.
Charges at the highest rate feasible based on battery and charger. Typically 20-25% of battery capacity. Takes the battery up to around 70-75% of battery capacity.
Charge rate typically around 10-15% of battery capacity. This allows charge to be evenly distributed on plates.
Maintains the battery at over 95% charge without overcharging.
Batteries can be charged from the vehicle alternator or from a 240v source such as the home power or generator. A good multi-stage charger should always be used to ensure that the battery is charged to the maxi,u, possible, and the battery life is not reduced unnecessarily.
Batteries can be charged from a 240v supply using a multi-stage charger. 240v sources include home supply, generator, caravan parks.
Batteries can be charged from the vehicle alternator via a DC-DC multi-stage charger.
Batteries can be charged from solar panels via a suitable solar regulator.
Portable 12 Chargers
Another option is using a portable petrol powered 12v charger. This uses an alternator to provide the 12v power for charging. One example is the Christie’s Battery Charger.