| Usually lurking under your bonnet, the battery is one of the most important items in your 4WD, because let’s face it, if it doesn’t work properly, then neither does anything else. Yet it is largely ignored - and often neglected - until it does let you down. But has the battery really let you down, or have you let it down? The reality is that you have probably let yourself down through simply not paying a little attention to that plastic box full of electricity nestled in an out-of-the-way corner of your 4WD. While the average battery life is around three and a half years, with proper maintenance most batteries will last far longer. So what is exactly involved in “proper” maintenance of a battery? According to AA Mobile Battery Services, there are five major points that should be taken into consideration - First is ensuring that your general engine condition is good. Poor engine condition can overload the battery, so keeping the engine in top condition with regular servicing is – and let’s face it, should always be – a priority. Secondly, under-charging and over-charging will quickly reduce the battery’s life, so regularly checking the charge rate is also important. Keeping your battery clean is another consideration, as this can reduce the rate of battery discharge. Using hot, soapy water to clean the case is recommended, remembering to dry it off well. Also, ensuring that the terminals are kept clean is important. Checking that your battery is secure at all times is also important, as vibration can cause damage to the battery case and plates. Inspect the terminals regularly too, because loose terminals can also cause problems. Finally, regular use is an important factor in keeping your battery in top health. Without regular charging, your battery will run down, simple as that. AA Mobile Battery Services recommends that you try to take at least a steady one-hour daylight drive each week. While this is all fine and well if the vehicle is your daily-driver, it isn’t quite so practical for a dedicated off-road 4WD. This is where a good trickle-charger comes in; keeping the battery topped-up with juice, while not over-charging it. Ensuring your battery never runs completely flat is a very important consideration, as every time it does run flat, the battery loses a bit more life. If, however, it does run completely flat, then proper charging is vital to its longevity. Most people think a quick 15-20 minute drive on the open road is enough to charge the battery, but in reality it takes much longer than that. In fact, a run from Auckland to Taupo is more like it. Instead, charging the battery overnight using a good-quality trickle charger is the best way to do it. Over-charging is also damaging to a battery, so a charger that won’t continue to charge when the battery is full is important. But it isn’t just old batteries in older cars that require regular maintenance; new vehicles require regular attention too, as the demands placed on their batteries is also far higher. While it seems counter-productive in this energy-conscious era that we are building vehicles that demand more and more current, this is the reality as the vehicle-buying public expects more creature comforts and more safety and driver-aid functions. Whereas the power requirement of a vehicle electrical system in the 1970s was 600W, it had more than tripled by the year 2000. Now, there is a power requirement of up to 8kW in the starting phase alone! Where we once had the single body control module (BCM) commonly performing several vehicular functions, such as the central locking, power window and anti-theft systems, we now have electronic brake force distribution, parking distance control, multiple air bag circuits, adaptive cruise control, lane change assist; the list goes on. All of these functions are live under normal driving conditions, and they are drawing considerable battery current to remain active. Couple these safety functions with complex navigation and entertainment systems, electric seats and the many other added luxuries which are growing in presence, and you are left with a considerable amount of total current draw. While modern batteries – and the associated charging systems that keep them topped up – are designed to deal with all extra demands placed on them, adding accessories for your off-roading also places extra demand. Winches, fridges, inverters and the like all run off your vehicle’s battery, which is why, if you have a number of these power-draining accessories, you should consider making that battery plural and add a dual battery system to your 4WD. A dual battery system adds another battery to your 4WDs electrical system, leaving the original battery to deal with the ordinary demands placed on it by the car’s electrical systems, while the additional battery deals with the accessories. The second battery should be either a deep cycle type, designed for slower release of energy – as opposed to a normal “starter” battery which is designed for large fast outputs – or a hybrid which combines the features of both. Most 4WD vehicles have a factory installed 80 or 100 Amp alternator capable of providing enough current to partially charge a large deep cycle battery. However, a vehicle’s alternator was never designed to fully charge (100 percent) the main vehicle battery. |
It was however designed to maintain the charge of the main vehicle battery and run the electrical loads (i.e. lights, radio etc.) once the vehicle is running. |
